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Increasing Levels of Physical Disturbance Affect Soil Nematode Community Composition in a Previously Undisturbed Ecosystem Cover

Increasing Levels of Physical Disturbance Affect Soil Nematode Community Composition in a Previously Undisturbed Ecosystem

Open Access
|Jul 2022

Full Article

Soil is indispensable for the sustenance of life. Soil provides essential resources for human activities such as agriculture, buildings, and industries (Brussaard, 1997). Several biological processes are continuously active in the soil and play an important role in the replenishment of soil resources and ecosystem maintenance (Young and Crawford, 2004). Biological processes in the soil are due to the dynamic interactions of diverse assemblages of living organisms including unicellular bacteria and protozoa to multicellular nematodes, earthworms, and arthropods (Giller et al., 1997; Bach et al., 2020). Diverse soil organisms support several biological processes such as organic matter decomposition, mineralization, nutrient cycling, and controlling pests and diseases (Brussaard, 1997; Heinen et al., 2018), which directly and indirectly affect crop growth and quality (Swift et al., 2004; Giller et al., 2005). Among multicellular soil organisms, nematodes are by far the most abundant (Porazinska et al., 2009; Lu et al., 2020; van den Hoogen et al., 2020). Nematodes are at the center of the soil food web by interacting with several other soil trophic groups in the lower hierarchy of the soil food web, with plants, bacteria, and fungi serving as food for nematodes; in turn, trophic groups in the higher hierarchy of the soil food web, such as predatory mites, eat nematodes (Moore, 1994; Roger-Estrade et al., 2010).

Nematodes play a pivotal role in organic matter decomposition (Freckman, 1988; Beare et al., 1992; Yeates and Coleman, 2021), mineralization (Yeates, 1979; Griffiths, 1989; Neher, 2001; Sikder and Vestergård, 2020), and uptake of nutrients by plants (Ingham et al., 1985; Gebremikael et al., 2016). Nematodes feeding on bacteria and fungi promote mineralization and release nutrients into the soil, thereby regulating decomposition (Ingham et al., 1985). Since nematodes are ubiquitous, functionally diverse, and abundant, they can be used to gauge the condition of structure and function of soil food webs (Bongers, 1990; Bongers and Bongers, 1998; Ferris et al., 2001; Neher, 2001). Nematodes have been categorized into different trophic groups such as bacterial feeders, fungal feeders, plant feeders, predators, and omnivores based on their stoma and esophagus morphology (Yeates et al., 1993). Additionally, a colonizer-persister (c-p) scale comprising five levels has been developed for nematodes ranging from colonizers (c-p 1) with high fecundity rate, short generation time, and toleration of disturbances, to persisters (c-p 5) with low fecundity rate, long generation time, and sensitivity to disturbances (Bongers, 1990). The c-p scale reflects the continuum of r- and K-strategists. Nematode community indices have been used to monitor ecological conditions of soil and the influence of agricultural activities on nematodes (Sohlenius et al., 1987; Bongers, 1990; Freckman and Ettema, 1993; Neher et al., 1995; Wardle et al., 1995).

Agricultural activities affect soil structure, biological activity, and processes such as decomposition, mineralization, and nutrient cycling by altering the physicochemical properties of soil (Stinner et al., 1984; Dick et al., 1988; Fraser et al., 1994). Notably, agricultural practices such as cultivation, crop rotation, tillage, and pesticide application have diverse impacts on plants, soils, and soil organisms (Elliott and Cole, 1989). Tillage alters soil properties such as moisture, temperature, aeration, and organic matter content and ultimately affects organisms that are living in the soil (Kladivko, 2001; Holland, 2004; Golabi et al., 2014). Furthermore, tillage disrupts the relationship between soil organisms by either killing or injuring them or exposing them to predators (Altieri, 1999; Roger-Estrade et al., 2010). Nematodes are more responsive to mechanical disturbance of soil than surface-dwelling invertebrates (Wardle et al., 1995). Tillage affects nematodes directly by altering pore size and disrupting the continuity of water films needed by nematodes and indirectly by affecting the lower trophic groups such as bacteria and fungi (Wardle et al., 1995).

Surface litter is essential for energy flow in the soil food webs (Attiwill and Adams, 1993). Removal of surface litter affects the dynamics of decomposition, which has a significant effect on the soil C pools (Wu et al., 2018). Surface litter removal decreases the resources available for nematodes, which affects the processes in the soil and alters the soil C distribution (Wu et al., 2021).

The effect of different types of physical disturbances on nematode communities has been previously investigated in agricultural ecosystems, i.e., those previously tilled or disturbed (Lenz and Eisenbeis, 2000; Okada and Harada, 2007; Rahman et al., 2007; Dong et al., 2013; Forge et al., 2015; Sánchez-Moreno et al., 2015; Zhang et al., 2015, 2019; Zhong et al., 2017; Wu et al., 2021). However, the effect of physical disturbances on soil organisms can be better evaluated by conducting experiments in undisturbed ecosystems, where soil organisms were never exposed to any kind of disturbances. Therefore, the main objective of this study was to examine the effect of increasing levels of physical disturbance on nematode communities in an undisturbed forest ecosystem. We hypothesized that the increase in the level of physical disturbance would negatively affect nematode communities.

Materials and Methods

Site description

A field experiment was conducted from April 2017 to May 2018 in a secondary mixed deciduous forest ecosystem dominated by nut-bearing oak and hickory species of trees in Farragut, TN, USA (35 º 54¢32N, 84 º 11¢372W; 311 m elevation). The experimental site is located in a temperate and seasonal climate with a mean annual temperature of 15.3°C and a mean annual precipitation of 1,224 mm. The soil at this site is classified as Minvale-Bodine-Fullerton complex. The experimental site had not been disturbed for at least 50 yr before the experiment was laid out. An understory was absent, and groundcover was negligible. The site sloped slightly toward the northwest.

Experimental design

The experiment included four treatments with increasing levels of physical disturbance. The first treatment was a control with no disturbance; the second treatment was surface litter removed (SLR) with no litter and no vegetation; the third treatment was tilling 15 cm deep with a rototiller every 2 mon after surface litter removal (R2M); the fourth treatment was tilling 15 cm deep every 2 wk after surface litter removal (R2W). Litter and vegetation were cleared every 2 wk from all the treatments except for the control. Each treatment was replicated thrice. Each plot was 2 m ´ 2 m and separated by a 2-m distance. The design of the experiment was a completely randomized design with repeated measures. The experiment was started in April 2017 and concluded in May 2018.

Soil sampling

Soil samples were collected from all the plots in April 2017 before starting the experiment and subsequently samples were collected every 2 mon: June 2017, September 2017, November 2017, January 2018, and May 2018. The interval between the tillage and sampling was 2 mon for R2M treatment and 2 wk for R2W treatment. At each sampling time, five soil cores, each having a 2-cm diameter and a 20-cm depth, were randomly collected from each plot. Soil samples from each plot were pooled into a plastic bag to prevent drying of soil, and then transported in a cooler to the laboratory where they were subsequently stored at 4°C before extracting nematodes on the next day.

Nematode extraction and identification were carried out as follows: Composite soil samples were thoroughly homogenized and 100 cm3 of each soil sample was used for extraction of nematodes through a sugar flotation-centrifugation method (Jenkins, 1964). Extracted nematodes from each sample were counted and the first 150 nematodes were identified to genus level using a differential interference contrast microscope. Proportions of each taxon were extrapolated to the entire sample. The identified nematode genera were assigned to their respective trophic groups: bacterial feeders (BF), fungal feeders (FF), plant feeders (PF), omnivores (OM), and predators (PR) (Yeates et al., 1993), and colonizer-persister (c-p) scale was established based on their life history characteristics and survival strategies associated with r- and K-selection. Nematodes with c-p 1 (enrichment opportunistic nematodes) and c-p 2 (mostly microbial and plant feeders) values are considered colonizers (r-selected), with small size, short life span, high fecundity, and high tolerance to environmental disturbances. Nematodes with c-p value 5 (mostly predators and omnivores) are persisters (K-selected), long-lived nematodes with low fecundity, slow development, and high sensitivity to environmental disturbances. (Bongers 1990).

Nematode ecological indices

The following ecological indices were calculated to assess the structure and functional role of nematode communities in soil food webs of increasing levels of physical disturbance: Simpson’s dominance index (λ), λ = ΣP2 (Simpson, 1949); Shannon–Weaver index (H´), H´ = –ΣiPilnPi, where P is the proportion of individuals in the ith taxon (Shannon, 1948); maturity index (MI) for free-living taxa were computed as MI = Σ[CP-value (i) × f(i)]/[total numbers of nematodes], where i is the individual taxon and fi is the frequency of taxa in the sample (Bongers, 1990). MI is used to evaluate the functioning and condition of a soil ecosystem as a consequence of environmental disturbance. MI values range from 1 to 5. A high MI suggests more abundant and diverse nematodes of higher c-p classes and a less disturbed ecosystem. A low MI suggests more abundant and diverse nematodes of lower c-p classes and a highly disturbed ecosystem. Plant-parasitic index (PPI) was calculated for plant-parasitic genera (Yeates and Bongers, 1999). Nematode channel ratio (NCR) indicates the decomposition pathway of the soil food web (Yeates and Bongers 1999). NCR is calculated as NCR = bacterial feeders/(bacterial feeders + fungal feeders) and ranges from 0 (fungi-dominated) to 1 (bacteria-dominated). Soil food web indices were calculated based on nematode functional guilds determined by the combination of c-p groups and trophic groups (Ferris et al., 2001). Soil food web indices include the Basal Index (BI), an indicator of the disturbed condition of soil food webs; Channel Index (CI), an indicator of decomposition of organic matter mediated by fungi; Enrichment Index (EI), an indicator of the predominance of bacterial feeders and enrichment conditions; and Structure Index (SI), an indicator of structured soil food webs with high trophic linkage (Ferris et al., 2001). Soil food web indices were calculated using the Nematode Joint Indicator Analysis tool (Sieriebriennikov et al., 2014).

Nematode metabolic footprints

Functional metabolic footprints (FMF) of nematode communities in soil food webs of increasing levels of physical disturbance were calculated using the Nematode Joint Indicator Analysis tool (Sieriebriennikov et al., 2014). FMF was calculated to evaluate the changes in the metabolic activity and flow of C into the soil food webs (Ferris, 2010). The total area of FMF is partitioned into enrichment footprint (efoot) indicating lower trophic groups (c-p 1–2) and structure footprint (sfoot) indicating higher trophic groups (c-p 3–5). The efoot is the metabolic footprint of lower trophic-group nematodes (c-p 1–2) whose population rapidly increases due to the increase in resources. The sfoot is the metabolic footprint of higher trophic group nematodes (c-p 3–5) with regulatory function. In an FMF graph, the y-axis represents the efoot, and the x-axis represents the structural footprint. In the FMF graph, the y-axis coordinates (EI– 0.5Fe/k and EI+ 0.5Fe/k) and x-axis coordinates (SI– 0.5Fs/k and SI+ 0.5Fs/k) were sequentially joined to depict the metabolic footprints of nematode communities. Fs indicates higher trophic groups (c-p 3–5) and Fe indicates lower trophic groups (c-p 1–2). The adjusted k value is 4 (Ferris, 2010).

Statistical analysis

Overall richness and abundance of nematodes were estimated for each sample. In addition, nematode richness and abundance for each trophic group and each c-p class at each time point were estimated. Statistical analyses were performed to compare the overall nematode richness and abundance as well as the richness and abundance of each trophic group and each c-p class across different treatments at different time points. Normality of residuals and equal variance were assessed using the Shapiro–Wilk statistic and visual observation of histograms and data were ln(x + 1)-transformed prior to statistical analysis. Analysis of variance with repeated measures was conducted with SAS (Glimmix procedure, SAS Institute, Cary, NC) and least square means were compared with Tukey’s LSD with a significance level of P < 0.05.

Changes in community structure with increasing levels of physical disturbance over time were visualized by nonmetric multidimensional scaling (NMDS) ordination with the Bray–Curtis distance matrix. Permutational multivariate analysis of variance (PERMANOVA; Anderson, 2001) was used to assess the significance of the differences among nematode community composition of the four treatments. The similarity percentage analysis (SIMPER) was used to determine the contribution of nematode genera to dissimilarities between treatments with a significance level of P < 0.05. All analyses were performed using the functions metaMDS, adonis, and simper in the vegan package of R, version 3.3.3 (Oksanen et al., 2020).

Results

Nematode abundance and community composition

In total, 56 genera were identified at different levels of physical disturbance across different sampling times. Of the 56 genera, 26 most abundant genera are listed in Supplementary Table 1. The nematode genera with zero abundance in most of the treatments at different sampling times were not considered for individual nematode analysis. Rhabditidae, Meloidogyne, Plectus, Filenchus, Aphelenchoides, Acrobeloides, Pseudacrobeles, and Gracilacus were the dominant taxa for all treatments at all sampling times.

The effect of increasing levels of physical disturbance on nematode abundance was statistically significant during January 2018 and May 2018 (P < 0.05) (Fig. 1). The overall abundance of nematodes was significantly lower in R2M compared to the control, SLR, and R2W treatments in January 2018 (P < 0.05) (Fig. 1). In addition, the overall abundance of nematodes was significantly lower in R2W compared to the control, SLR, and R2M treatments in May 2018 (P < 0.05) (Fig. 1). Although the effect of tillage on nematode overall abundance was not statistically significant, nematode overall abundance was consistently lower in R2M and R2W compared to the control and SLR treatment since June 2017 (Fig. 1). Similarly, the effect of increasing levels of physical disturbance on nematode richness was statistically significant during January 2018 and May 2018 (P < 0.05) (Fig. 2). Overall richness of nematodes was significantly lower in SLR, R2M, and R2W compared to the control in January 2018 (P < 0.05) (Fig. 2). The effect of tillage on nematode richness was more pronounced in the last sampling in May 2018 in which nematode richness was significantly decreased in R2M and R2W compared to the control and SLR treatments (P < 0.05) (Fig. 2). Although the effect of tillage on nematode overall richness was not statistically significant, the overall richness of nematodes was consistently lower in R2M and R2W compared to the control and SLR treatments from November 2017 (Fig. 2)

Figure 1

Effect of increasing levels of physical disturbance on genus-level nematode abundance. Box plots representing the number of nematodes per 100 cm3 of soil in control, SLR, R2M, and R2W at each sampling time. Lower and upper box boundaries represent 25th and 75th percentiles, respectively; line inside the box indicates median; and lower and upper error lines represent 10th and 90th percentiles, respectively. Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey–LSD test). R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Figure 2

Effect of increasing levels of physical disturbance on genus-level nematode richness. Box plots representing the number of genera per 100 cm3 of soil in control, SLR, R2M, and R2W at each sampling time. Lower and upper box boundaries represent 25th and 75th percentiles, respectively; line inside the box indicates median; and lower and upper error lines represent 10th and 90th percentiles, respectively. Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey–LSD test). R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Among 56 genera, 20 taxa were bacterial feeders, 18 taxa were plant feeders, 7 taxa were fungal feeders, 6 genera were omnivores, and 5 taxa were predators. The effect of increasing levels of physical disturbance on nematode abundance and richness of each trophic group was analyzed. Increasing levels of physical disturbance significantly affected the abundance of bacterial feeders, fungal feeders, predators, and omnivores during the last two samplings (January 2018 and May 2018) (P < 0.05). However, the abundance of plant feeders was not significantly affected Supplementary Table 2). Tillage significantly lowered the abundance of bacterial feeders, predators, and omnivores in R2M and R2W treatments compared to control during the last sampling in May 2018 (P < 0.05) (Supplementary Table 2). In addition, the abundance of fungal feeders was also significantly affected by the tillage treatments, R2M and R2W during the last two samplings, January 2018 and May 2018, respectively (P < 0.05) (Supplementary Table 2). On the other hand, tillage significantly affected the richness of bacterial feeders, predators, and omnivores, especially during the last two samplings (January 2018 and May 2018) (P < 0.05) (Supplementary Table 2). The richness of bacterial feeders was significantly lower in R2W compared to the control and SLR treatments during the last two samplings (P < 0.05). Additionally, the richness of predators was significantly lower in R2M and R2W compared to SLR treatment, whereas the richness of omnivores was significantly decreased in R2M and R2W compared to the control and SLR treatments (P < 0.05) (Supplementary Table 2).

Increasing levels of physical disturbance significantly affected the abundance of 10 genera, Acrobeles, Alaimus, Aporcelaimellus, Boleodorus, Ceratoplectus, Clarkus, Dorylaimida, Filenchus, Prismatolaimus, and Tripyla during the last two samplings of January 2018 and May 2018 (P < 0.05) (Supplementary Table 1). The abundance of Acrobeles, Aporcelaimellus, and Boleodorus was significantly reduced with the increase in the level of physical disturbance in May 2018 (P < 0.05) (Supplementary Table 1). Tillage significantly reduced the abundance of Alaimus in R2M and R2W compared to the control and SLR treatments during the last sampling of May 2018 (P < 0.05) (Supplementary Table 1). The abundance of Ceratoplectus and Filenchus was significantly lower in the tillage treatments, R2M and R2W compared to the control in January 2018 and May 2018 (P < 0.05) (Supplementary Table 1). The abundance of Clarkus, Dorylaimida, and Tripyla was significantly decreased in R2M and R2W treatments compared to the control during the last sampling, May 2018 (P < 0.05) (Supplementary Table 1). Tillage significantly reduced the abundance of Prismatolaimus in the R2W treatment compared to the control during January 2018 and May 2018 (P < 0.05) (Supplementary Table 1). Removal of surface litter resulted in a significant decrease in the abundance of Acrobeles, Aporcelaimellus, and Boleodorus compared to the control during the last sampling period, May 2018 (P < 0.05) (Supplementary Table 1).

The effect of increasing levels of physical disturbance on nematode abundance and richness of each c-p class was also analyzed. Increasing levels of physical disturbance did not affect the abundance of c-p 1 and c-p 3 class nematodes whereas the impact was significant in the cases of c-p 2, c-p 4, and c-p 5 classes (P < 0.05). The nematode abundance of the c-p 2 class was lower in R2M and R2W compared to the control in the last two samplings of January 2018 and May 2018 (P < 0.05) (Supplementary Table 3). Similarly, the abundance of c-p 5 class nematodes was lower in R2M and R2W than in the control during the last sampling, May 2018 (P < 0.05) (Supplementary Table 3). The abundance of c-p 4 class nematodes was decreased in R2M and R2W compared to the control and SLR treatments during May 2018 (P < 0.05) (Supplementary Table 3). Increasing levels of physical disturbance did not affect the richness of c-p 1, c-p 3, and c-p 5 class nematodes whereas they significantly affected the richness of c-p 2 and c-p 4 classes (P < 0.05) (Supplementary Table 3). The richness of nematodes in the c-p 2 class was significantly lower in R2M and R2W compared to the control during January 2018 and May 2018 (P < 0.05). Moreover, the richness of nematodes in the c-p 4 class was significantly reduced in R2W compared to the control in January 2018 (P < 0.05). In the last sampling, tillage significantly reduced the richness of c-p 4 class nematodes in R2M and R2W compared to the control and SLR (P < 0.05) (Supplementary Table 3).

Nematode ecological indices

A significant effect of increasing levels of physical disturbance was observed on the values of λ, H´, EI, and SI (P < 0.05) (Supplementary Table 4). The value of λ significantly increased with the increasing levels of physical disturbance. The value of λ was significantly lower in the control than in R2W in January 2018 and lower in the control compared to R2M and R2W during May 2018 (P < 0.05) (Supplementary Table 4). The value of H´ significantly decreased with the increasing levels of physical disturbance. The value of H´ was significantly lower in R2W compared to the control during January 2018, and lower in R2M and R2W than in the control during the last sampling, May 2018 (P < 0.05) (Supplementary Table 4). MI value significantly reduced with the increase in the level of physical disturbance. MI was significantly lower in R2W than in control treatment during January 2018, and lower in R2M and R2W compared to the control and SLR during May 2018 (P < 0.05) (Supplementary Table 4). PPI value was significantly higher in R2M and R2W compared to the control during the last sampling, May 2018 (P < 0.05) (Supplementary Table 4). EI value significantly increased with the increasing levels of physical disturbance. EI was significantly higher in R2W compared to the control during the last two samplings, January and May 2018 (P < 0.05) (Supplementary Table 4). In contrast, SI significantly decreased with the increasing levels of physical disturbance. SI was significantly lower in R2W compared to the control and SLR during January 2018, and lower in R2M and R2W than in the control and SLR during the last sampling, May 2018 (P < 0.05) (Supplementary Table 4).

Nematode metabolic footprints

A significant effect of increasing levels of physical disturbance was observed on efoot and sfoot (P < 0.05) (Supplementary Table 4). Tilling every 2 wk resulted in a significant reduction of efoot compared to the control and other treatments during May 2018 (P < 0.05) (Supplementary Table 4). The sfoot was significantly lower in R2W than in the control and SLR treatments during January 2018 and significantly lower in R2M and R2W treatments compared to the control and SLR treatments during the last sampling in May 2018 (P < 0.05) (Supplementary Table 4). The FMF area of nematode communities was decreased with the increasing levels of physical disturbance (Fig. 3). The area of FMF of R2M and R2W was decreased over time compared to the control and SLR treatments. All the treatments were clustered together in the same quadrat until November 2017 and started spreading out in January 2018. In May 2018, control and SLR treatments were located in quadrat B, which indicated a maturing ecosystem with enriched soil nutrients and a well-structured soil food web, while R2M and R2W were located in quadrat A, which indicated a disturbed and poorly structured soil food web. The FMF indicates the total area of the enrichment and sfoot as demonstrated in Figure 3.

Figure 3

FMF of nematode communities subjected to different levels of physical disturbance: control, SLR, R2M, and R2W. The vertical axis represents the efoot, and the horizontal axis represents the sfoot. The FMF is depicted by sequentially joining points: (SI– 0.5Fs/k, EI); (SI+ 0.5Fs/k, EI); (SI, EI– 0.5Fe/k); and (SI, EI+ 0.5Fe/k). Fs represents sfoot and Fe represents efoot (Ferris, 2010). The adjusted k value is 4. FMF, functional metabolic footprints; R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; sfoot, structure footprint; SLR, surface litter removed.

The relationship between nematode abundance and treatments

NMDS analysis of nematode communities showed a significant differentiation in nematode communities with increasing levels of physical disturbance during January 2018 (Fig. 4; PERMANOVA: R2 = 0.42, F = 1.93, P = 0.044, Stress = 0.08), and May 2018 (Fig. 4; PERMANOVA: R2 = 0.46, F = 2.32, P = 0.015, Stress = 0.07). During January 2018, R2M and R2W treatments negatively impacted Boleodorus, Dorylaimida, Acrobeles, Prismatolaimus, Ceratoplectus, Alaimus, Plectus, Gracilacus, Tylocephalus, and Helicotylenchus. Conversely, Aphelenchoides, Rhabditidae, Diplogasteridae, Ditylenchus, Acrobeloides, and Ecphyadophora were positively associated with R2M and R2W (Fig. 4). Along with the aforementioned taxa, tillage negatively impacted Aporcelaimellus, Clarkus, Tripyla, Filenchus, Pseudacrobeles, and was positively associated with Meloidogyne, Xenocriconemella, and Teratocephalus during May 2018 (Fig. 4). SIMPER analysis revealed that the average dissimilarity of the nematode communities increased between the control and other treatments with increasing physical disturbance during January and May 2018 (January 2018: control vs. SLR = 43.2%, control vs. R2M = 49.5%, control vs. R2W = 49%; May 2018: control vs. SLR = 40.2%, control vs. R2M = 42.2%, control vs. R2W = 56.3%). According to the SIMPER test, Filenchus contributed most to the dissimilarity followed by Xenocriconemella, Gracilacus, Plectus, Pseudacrobeles, Ditylenchus, Meloidogyne, Prismatolaimus, Helicotylenchus, and Acrobeloides between the control and other treatments during January 2018. Similarly, Meloidogyne contributed most to the dissimilarity followed by Filenchus, Xenocriconemella, Acrobeles, Gracilacus, Helicotylenchus, Alaimus, Rhabditidae, Acrobeloides, Plectus, Prismatolaimus, and Ceratoplectus between the control and other treatments during May 2018 (Supplementary Table 5).

Figure 4

Biplot representing the NMDS performed on nematodes communities subjected to different levels of physical disturbance: control, SLR, R2M, and R2W in April 2017 (PERMANOVA: P = 0.92, NMDS; Stress = 0.05), June 2017 (PERMANOVA: P = 0.117, NMDS; Stress = 0.09), September 2017 (PERMANOVA: P = 0.075, NMDS; Stress = 0.11), November 2017 (PERMANOVA: P = 0.226, NMDS; Stress = 0.11), January 2018 (PERMANOVA: P = 0.044, NMDS; Stress = 0.08), and May 2018 (PERMANOVA: P = 0.015, NMDS; Stress = 0.07). Treatments are depicted using arrows while nematodes are depicted with dots. NMDS, Nonmetric multidimensional scaling; PERMANOVA, Permutational multivariate analysis of variance; R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Discussion

Increasing levels of physical disturbance on nematode abundance and community composition

Nematodes play a key role in maintaining and regulating several biological processes, crucial for soil and plant health (Yeates and Coleman, 1982; Liang et al., 2009). Tillage is one of the most intensively used agricultural management strategies, affecting the most important players in soil biological processes such as decomposition, mineralization, and nutrient cycling (Stinner et al., 1984; Dick et al., 1988; Fraser et al., 1994). Many studies have been conducted to evaluate the effect of different types of physical disturbances on nematode communities and other soil organisms in agricultural ecosystems (Lenz and Eisenbeis, 2000; Okada and Harada, 2007; Rahman et al., 2007; Dong et al., 2013; Forge et al., 2015; Sánchez-Moreno et al., 2015; Zhang et al., 2015, 2019; Zhong et al., 2017; Wu et al., 2021). However, this report is the first on the effect of tillage in terms of increasing levels of physical disturbance on nematode populations in a previously undisturbed forest ecosystem.

Tillage significantly reduced the overall abundance and overall richness of nematode communities over time in R2M and R2W, which was attributed to the decrease in the abundance of bacterial feeders, fungal feeders, predators, and omnivores and a decrease in the richness of bacterial feeders, predators, and omnivores. Tillage directly affects nematode communities by abrasion and indirectly by changing the food web, temperature, moisture, and aeration of soil in tillage treatments compared to the control, which was undisturbed (Kladivko, 2001; Holland, 2004; Rahman et al., 2007; Golabi et al., 2014). Our findings are in agreement with the studies conducted by Freckman and Ettema, (1993), Fu et al. (2000), Okada and Harada, (2007), Treonis et al. (2010), Dong et al. (2013), Sánchez-Moreno et al. (2015), Zhang et al. (2015), Zhong et al. (2017), and Pothula et al. (2019), who reported that physical disturbances reduced nematode abundance in agricultural ecosystems. However, it should be noted that our tillage regime was far more intense than that of any agricultural system (1 or 2 times/monthly vs. 1 or 2 times yearly). In some studies, the effect of tillage in agricultural ecosystems was noticed immediately after the first tillage (Lenz and Eisenbeis, 2000); however, in our study, the tillage effect was significantly evident after 9 mon. This may be due to the differences in forest and agricultural ecosystems and their response to tillage regimes. Removal of surface litter, SLR, resulted in a significant decrease in the overall richness of nematodes compared to control during January 2018. Our outcomes are in agreement with the study conducted by Wu et al. (2021). However, the significance was not evident during the subsequent sampling. On the other hand, the higher overall abundance and overall richness of nematodes in the control treatment could be attributed to the large amount of litter content and the absence of physical disturbances in the control treatment.

Among nematode trophic groups, tillage significantly reduced the abundance and richness of bacterial feeders over time. Many studies conducted in agricultural fields have reported that tillage stimulated the bacterial feeding nematodes due to the probable increase in bacterial biomass with the incorporation of organic matter (Andren and Lagerlof, 1983; Parmelee and Alston, 1986; Ettema and Bongers, 1993; Lenz and Eisenbeis, 2000; Liphadzi et al., 2005; Sánchez-Moreno et al., 2006). However, the decrease in bacterial feeders in our study was attributed to the decrease in the abundance of Acrobeles, Alaimus, Ceratoplectus, and Prismatolaimus. Moreover, the decrease in bacterial feeders was also attributed to the declining trend of the abundance of Plectus and Pseudacrobeles, even though the difference was not statistically significant. This may be due to the fact that organic litter was periodically removed from the tillage treatments. Similarly, several studies have reported that Prismatolaimus is reduced by cultivation (Fiscus and Neher, 2002; Ferris and Bongers, 2006; Minoshima et al., 2007; Sánchez-Moreno et al., 2009; Zhao and Neher, 2013; Zhang et al., 2019).

Tillage significantly reduced the abundance but not the richness of fungal feeders. There is a discrepancy in reports on the response of fungal feeding nematodes to tillage practices. Some studies have reported that tillage increased the fungal feeding nematode communities (Parmelee and Alston, 1986; Liphadzi et al., 2005; Sánchez-Moreno et al., 2006; Dong et al., 2013). However, Okada and Harada (2007) found that fungal-feeding nematodes increased in a no-till system. This discrepancy may be due to a complex set of factors, including geographic location, type of vegetation, soil type, and ecosystem. Unlike the case in agricultural ecosystems, tillage decreased the abundance of Filenchus in our study. Studies conducted in agriculture ecosystems have noted that Filenchus has an excellent capacity to tolerate disturbances and occurs in soils with abundant organic matter (Fiscus and Neher, 2002; Okada and Kadota, 2003; Zhang et al., 2015, 2019). This disagreement may be due to the condition of the ecosystem that was undisturbed and plausibly due to the consistent removal of surface litter in our study.

Among nematodes belonging to the higher hierarchy of the soil food web, tillage significantly reduced the abundance and richness of predators and omnivores, which are sensitive to disturbances (Bongers 1990; Ferris et al., 2001). Similar results were reported by Dong et al. (2013), Zhang et al. (2015), and Zhang et al. (2019). The tillage treatments negatively impacted the abundance of Aporcelaimellus, Clarkus, Dorylaimida, and Tripyla, resulting in the decline of predators and omnivores. The sensitivity of Aporcelaimellus to tillage was previously reported in the agricultural ecosystem by Zhong et al. (2016, 2017). Similarly, Dorylaimida was also reported to be lowered by cultivation (Fiscus and Neher, 2002; Rahman et al., 2007; Zhang et al., 2012). Fiscus and Neher (2002) reported that Clarkus is tolerant to direct effects of tillage in agricultural ecosystems; however, in our study, the abundance of Clarkus was reduced with increasing levels of physical disturbance. This incongruity probably resulted as our study was carried out in an undisturbed forest ecosystem, where nematodes were not previously exposed to any physical disturbances and therefore may not have been selected for it. Unlike other trophic groups, the abundance and richness of plant-feeding nematodes did not differ significantly in tillage treatments compared to control. The response of plant-feeding nematodes to tillage practices is complicated to interpret as they are more closely associated with plants than with soil (Sánchez-Moreno et al., 2006).

The effect of tillage disturbances on nematode communities according to c-p classes was also assessed. The abundance and richness of c-p 2, c-p 4, and c-p 5 class nematodes were significantly decreased by tillage. Nematodes belonging to lower c-p classes are r-strategists, which are characterized by a high fecundity rate, short generation time, and tolerance to disturbances (Bongers, 1990; Ferris et al., 2001). Although c-p 2 class nematodes belong to lower c-p classes, the abundance and richness of c-p 2 class nematodes were significantly reduced by tillage. The decrease in c-p 2 class nematodes in tillage treatments was due to the decrease in the abundance of Acrobeles, Boleodorus, Ceratoplectus, and Filenchus. The abundance and richness of nematodes of higher c-p classes (c-p 4 and c-p 5) were significantly reduced by tillage disturbances as these nematodes are sensitive to disturbances in the soil ecosystem (Bongers, 1990; Lenz and Eisenbeis, 2000; Ferris et al., 2001).

The significant differences between the control and SLR were not reflected in trophic and c-p group analyses. However, individual nematode analyses revealed that removal of surface litter resulted in a significant decrease in the abundance of Acrobeles, Aporcelaimellus, and Boleodorus. These three genera belong to different trophic groups: bacterial feeder, omnivore, and plant feeder, respectively. Further research at the genus level is needed to explain the impact of surface litter on different nematode genera. Overall, these results indicate that the sensitivity of individual nematode genera to increasing levels of physical disturbances is different, and the sensitivity should be considered to foresee the function of soil organisms in the soil.

Increasing levels of physical disturbance on nematode ecological indices

The nematode ecological indices are often used to assess the condition of the soil food web. l and H´ indicate the diversity of nematode communities. Increasing levels of physical disturbance increased the Simpson index (l) and decreased the Shannon diversity index (H´). This agreement indicates the decrease in diversity of nematode communities with the increase in the level of physical disturbance. The NCR value decreased with increasing levels of physical disturbance, indicating the shift of the decomposition pathway from bacterial to fungal dominated. The higher value of NCR in the control treatment suggested the predominance of the bacterial decomposition pathway. Our results are in agreement with Zhang et al., 2015 but not in concurrence with Okada and Harada, 2007 and Treonis et al., 2010, who reported a fungal-dominated decomposition channel in no-tillage. Our results indicated that the change in the decomposition channel may be due to the continuous removal of surface litter, which reduced the surface organic matter and shifted the decomposition channel from bacterial to fungal dominated. MI and PPI are used to assess the effect of disturbances on soil food webs. Our results showed that tillage significantly decreased MI values in both R2W and R2M compared to the control and SLR treatments during the last sampling in May 2018. On the other hand, the removal of surface litter did not affect the MI value. This indicates a lower abundance and diversity of higher c-p class nematodes in tillage treatments due to heightened levels of physical disturbances (Djigal et al., 2012; Grabau and Chen, 2016; Zhong et al., 2016; Zhong et al., 2017). However, tillage did not significantly affect PPI values as the abundance of plant feeders was not affected much in the tillage treatments. Our results suggested that the EI value significantly increased with the increasing levels of physical disturbance. Although the abundance of bacterial feeders belonging to the c-p 2 class declined drastically, the abundance of enrichment opportunists (c-p 1 nematodes) slightly decreased with the increase in levels of physical disturbance, which resulted in higher EI values in tillage treatments. In contrast, SI significantly decreased with the increasing levels of physical disturbance. The lower SI values in tillage treatments indicate that the ecosystem was disturbed with fewer predators and omnivores, which are sensitive to disturbances (Korthals et al., 1996; Ferris et al., 2001). Similar results were reported by Sánchez-Moreno et al. (2009) and Zhang et al. (2015).

Increasing levels of physical disturbance on nematode FMF

Nematode FMF were calculated to indicate the structure and function of soil food webs with different levels of physical disturbance. The nematode trophic footprints suggested the changes in the metabolic activity and flow of C into the soil food web through their respective trophic channels (Ferris, 2010). The value of efoot is considered as an indicator of the flow of C and energy through r-strategists, which are lower c-p values (1–2) (Ferris et al., 2012). The value of sfoot indicates the flow of C and energy through higher c-p values (3–5), which may regulate the function of soil food webs (Neher et al., 2004; Ferris et al., 2012). The higher value of efoot in the control treatment indicated higher productivity and turnover rates of the r-strategists and adequate resources (Vonk et al., 2013; Ito et al., 2015; Zhang et al., 2015; Zhong et al., 2017). Similarly, tillage drastically reduced the values of sfoot, which indicates the decrease in metabolic activity of both predators and omnivores in R2M and R2W treatments (Zhong et al., 2016).

The FMF area of nematode communities decreased with increasing levels of physical disturbance. FMF with a larger area in the control treatment during May 2018 indicated a higher metabolic activity and inflow of C, which was used for nematode production (Ferris, 2010). The high availability of organic matter in the control treatment increased the abundance of predators and omnivores and activated a stronger pathway through the predator channel, which may promote the stronger metabolic process and stability of the soil food web (Ferris, 2010; Thakur and Geisen, 2019; Kou et al., 2020). On the other hand, the FMF area was smaller in tillage treatments, indicating that smaller quantities of C were used for nematode production and lower metabolic activity due to the low availability of resources and lower predator-omnivore numbers (Ferris, 2010). All the treatments were clustered together in the same quadrat until November 2017 and started spreading out in January 2018. In May 2018, control and SLR treatments were located in quadrat B, which indicated a maturing ecosystem with enriched soil nutrients and a well-structured soil food web, while R2M and R2W were located in quadrat A, which indicated a disturbed and poorly structured soil food web (Ferris, 2010).

The relationship between nematode abundance and increasing levels of physical disturbances

Soil nematodes have been used as bioindicators to assess the effect of physical disturbances (Yeates, 2003). Our study revealed that different nematode genera had varying sensitivities to the physical disturbances. NMDS analysis of nematode communities revealed that soil nematode genera were clearly separated by increasing levels of physical disturbance during January and May 2018. The dissimilarity between the treatments indicates the progressive decrease in the abundance of nematode communities at R2M and R2W treatments. These declining trends generated significantly different nematode assemblages at all treatments during January and May 2018, as emphasized by PERMANOVA. All the nematodes belonging to higher c-p classes (c-p 4 and 5) and bacterial feeders of the c-p 2 class were negatively affected by the R2M and R2W treatments, while nematodes of lower c-p classes including bacterial feeders except c-p 2 class, fungal feeders, and plant feeders were not impacted by the tillage treatments. Nematodes of higher c-p classes such as Dorylaimida, Aporcelaimellus, Alaimus, Clarkus, and Tripyla were sensitive to physical disturbances (Bongers, 1990; Lenz and Eisenbeis, 2000; Ferris et al., 2001). Although bacterial feeders of the c-p 2 class belong to lower c-p classes, the abundance of c-p 2 class nematodes such as Tylocephalus, Acrobeles, Ceratoplectus, Plectus, and Pseudacrobeles was significantly reduced by tillage. The decrease in c-p 2 class nematodes in tillage treatments may be due to the continuous removal of organic matter (Ferris and Bongers, 2006). Tillage negatively impacted only a few plant feeders such as Helicotylenchus, Gracilacus, and Boleodorus. This declining trend of plant-feeding nematodes was in agreement with Lenz and Eisenbeis (2000) and Rahman et al. (2007). However, Meloidogyne, Xenocriconemella, and Ecphyadophora are positively associated with tillage. The response of plant-feeding nematodes to tillage practices is complicated to interpret as they are more closely associated with plants than with soil (Sanchez-Moreno et al., 2006). Furthermore, SIMPER analysis also revealed that the above-mentioned genera lead to significant dissimilarity among treatments.

Overall, this study gives an insight into the effect of increasing levels of physical disturbance on nematode communities in an undisturbed forest ecosystem, indicating that tillage reduced the abundance and richness of nematode communities, which was consistent with previous studies in the literature that were conducted in agricultural ecosystems. However, in this study, bacterial feeding nematodes belonging to the c-p 2 class responded differently compared to those of agricultural ecosystems. Tillage significantly reduced the abundance and richness of bacterial feeding nematodes of the c-p 2 class along with predators and omnivores, which belong to higher c-p classes. Moreover, tillage significantly reduced the FMF of nematodes, which indicates decreased metabolic activity, reduced C inflow, and poorly structured soil food webs. Unlike tillage, minimal disturbance such as removal of surface litter resulted in a significant reduction of very few nematode genera. Previous studies conducted in agricultural ecosystems determined that Clarkus, Filenchus, and Plectus were tolerant to tillage; however, they were found sensitive to tillage in our study. To understand this incongruity, further studies are needed to investigate whether these species are adapted to the physical disturbances in agricultural ecosystems. Overall, our study suggests that increasing levels of physical disturbance are detrimental to nematode community abundance and diversity that could affect ecosystem stability and sustainability. Also, our results affirmed that soil nematodes are highly sensitive to physical disturbances and therefore could be used as indicators of stability and functioning of the soil ecosystem.

Acknowledgments

We would like to thank James Phillips for lending his rototiller to conduct the experiment. We also thank Charles and Melodie Ledford for allowing us to conduct the experiment in their woodlands.

Supplementary Tables

Table S1

Abundance (individuals per 100 cm3 of soil) of nematode taxon in different treatments: control, SLR, R2M, and R2W at all sampling times. (mean ± pooled SE, n = 5).

TaxonAbbreviationTrophic groupsTimeControlSLRR2MR2W
RhabditidaeRhabBFApr-17115.67 ± 34.1996 ± 34.19177.67 ± 34.1996.67 ± 34.19
Jun-17147.67 ± 34.1957 ± 34.1956.33 ± 34.1961.67 ± 34.19
Sep-17134.67 ± 34.19120 ± 34.1993.67 ± 34.1930 ± 34.19
Nov-1730.67 ± 34.1946.67 ± 34.1960.67 ± 34.1920.67 ± 34.19
Jan-1822 ± 34.1927.33 ± 34.1915.33 ± 34.1923.33 ± 34.19
May-1846 ± 34.1934 ± 34.1933.33 ± 34.1921 ± 34.19
PlectusPlecBFApr-1755.67 ± 11.2326.33 ± 11.2329.33 ± 11.2330.33 ± 11.23
Jun-1772.33 ± 11.2340 ± 11.2316.33 ± 11.2320.33 ± 11.23
Sep-1750 ± 11.2363 ± 11.2310.67 ± 11.2317.67 ± 11.23
Nov-1729.67 ± 11.2322 ± 11.2311.67 ± 11.2312.67 ± 11.23
Jan-1840.67 ± 11.2321 ± 11.2310.33 ± 11.235.67 ± 11.23
May-1845.67 ± 11.2324.67 ± 11.2328 ± 11.236.67 ± 11.23
AcrobeloidesAcrdBFApr-1746.33 ± 12.8353.67 ± 12.8324 ± 12.8330 ± 12.83
Jun-1718.67 ± 12.8327 ± 12.8328.33 ± 12.8319 ± 12.83
Sep-1711.67 ± 12.8331.33 ± 12.8336.33 ± 12.8337.67 ± 12.83
Nov-1714.67 ± 12.8311.67 ± 12.8315 ± 12.8318 ± 12.83
Jan-1823.33 ± 12.8322 ± 12.8318.67 ± 12.8318.33 ± 12.83
May-1822.33 ± 12.8318 ± 12.8332.67 ± 12.8314 ± 12.83
PrismatolaimusPrisBFApr-177 ± 10.292.67 ± 10.292.33 ± 10.292.67 ± 10.29
Jun-1719 ± 10.2928 ± 10.296 ± 10.2912.33 ± 10.29
Sep-1728.33 ± 10.2937.67 ± 10.2920.67 ± 10.2941.67 ± 10.29
Nov-1743.67 ± 10.2937.33 ± 10.2924.67 ± 10.2913.67 ± 10.29
Jan-1824.67 ± 10.29a19.33 ± 10.29a,b6 ± 10.29a,b1 ± 10.29b
May-1821.67 ± 10.29a30.67 ± 10.29a,b10 ± 10.29a,b1.67 ± 10.29b
PseudacrobelesPseuBFApr-1720 ± 5.2822 ± 5.2811.67 ± 5.2811.33 ± 5.28
Jun-1718.67 ± 5.285.67 ± 5.286 ± 5.286.67 ± 5.28
Sep-1719.33 ± 5.288 ± 5.288.67 ± 5.281 ± 5.28
Nov-1715.67 ± 5.284.33 ± 5.2810.33 ± 5.289.33 ± 5.28
Jan-1837.33 ± 5.282 ± 5.288.33 ± 5.2812.33 ± 5.28
May-1814.67 ± 5.284 ± 5.282.67 ± 5.283 ± 5.28
AlaimusAlaiBFApr-170 ± 8.850 ± 8.850 ± 8.850 ± 8.85
Jun-1710.33 ± 8.855.33 ± 8.856.33 ± 8.850 ± 8.85
Sep-1733.67 ± 8.8513 ± 8.8520 ± 8.8516 ± 8.85
Nov-1731 ± 8.8576.33 ± 8.8544.33 ± 8.8515.33 ± 8.85
Jan-1810 ± 8.858 ± 8.850.67 ± 8.853 ± 8.85
May-1824.33 ± 8.85a38 ± 8.85a6.67 ± 8.85b0 ± 8.85b
AcrobelesAcrbBFApr-176.67 ± 7.022.67 ± 7.021.67 ± 7.021.33 ± 7.02
Jun-171.67 ± 7.026.33 ± 7.025.67 ± 7.027.67 ± 7.02
Sep-177.67 ± 7.0212.33 ± 7.0212.33 ± 7.022 ± 7.02
Nov-1721 ± 7.026 ± 7.0212 ± 7.021 ± 7.02
Jan-182.67 ± 7.0216.67 ± 7.025.67 ± 7.020 ± 7.02
May-1832.67 ± 7.02a9.67 ± 7.02b5.67 ± 7.02b0 ± 7.02b
TylocephalusTyloBFApr-1716.67 ± 2.74.67 ± 2.79.67 ± 2.75 ± 2.7
Jun-179.67 ± 2.77.67 ± 2.70.67 ± 2.76.33 ± 2.7
Sep-175.67 ± 2.73.33 ± 2.71.33 ± 2.71 ± 2.7
Nov-172.33 ± 2.71.33 ± 2.70 ± 2.73 ± 2.7
Jan-189 ± 2.72.33 ± 2.70 ± 2.70.67 ± 2.7
May-183.33 ± 2.70.67 ± 2.71 ± 2.70 ± 2.7
CeratoplectusCeraBFApr-173 ± 2.792.67 ± 2.792.33 ± 2.791 ± 2.79
Jun-175 ± 2.7912.33 ± 2.797.33 ± 2.795.33 ± 2.79
Sep-179.33 ± 2.795.33 ± 2.795 ± 2.791 ± 2.79
Nov-178.33 ± 2.798.33 ± 2.791 ± 2.790 ± 2.79
Jan-187 ± 2.79a1.33 ± 2.79a,b0 ± 2.79b0 ± 2.79b
May-1815 ± 2.79a3.33 ± 2.79a,b1 ± 2.79b0 ± 2.79b
TeratocephalusTeraBFApr-173 ± 2.621.67 ± 2.622.33 ± 2.620 ± 2.62
Jun-170 ± 2.621.67 ± 2.620.67 ± 2.620 ± 2.62
Sep-1712.33 ± 2.627 ± 2.622.33 ± 2.622 ± 2.62
Nov-173.33 ± 2.622.67 ± 2.620 ± 2.620 ± 2.62
Jan-185.33 ± 2.622 ± 2.620.67 ± 2.620.67 ± 2.62
May-181.33 ± 2.620 ± 2.620.67 ± 2.622.67 ± 2.62
CervidellusCervBFApr-171 ± 1.610 ± 1.611 ± 1.611 ± 1.61
Jun-170 ± 1.610 ± 1.610.67 ± 1.610.67 ± 1.61
Sep-172.33 ± 1.613.33 ± 1.611 ± 1.613 ± 1.61
Nov-171.67 ± 1.611 ± 1.611 ± 1.612.33 ± 1.61
Jan-185.67 ± 1.611.33 ± 1.612 ± 1.611 ± 1.61
May-185 ± 1.610.67 ± 1.613.33 ± 1.610 ± 1.61
DiplogasteridaeDiplBFApr-170 ± 1.210 ± 1.211.67 ± 1.210 ± 1.21
Jun-171.67 ± 1.210 ± 1.210.67 ± 1.212.67 ± 1.21
Sep-172.67 ± 1.213.67 ± 1.210 ± 1.210 ± 1.21
Nov-171 ± 1.210 ± 1.211.67 ± 1.210 ± 1.21
Jan-182.33 ± 1.210 ± 1.210.67 ± 1.210 ± 1.21
May-182.33 ± 1.210 ± 1.210 ± 1.211 ± 1.21
FilenchusFileFFApr-1755.33 ± 26.0252.33 ± 26.0265.67 ± 26.02113.67 ± 26.02
Jun-17158.67 ± 26.02111.67 ± 26.0275.67 ± 26.0294.67 ± 26.02
Sep-17116.33 ± 26.02196.33 ± 26.02133 ± 26.02123.33 ± 26.02
Nov-17106 ± 26.02130.33 ± 26.02142.67 ± 26.0263.67 ± 26.02
Jan-18191.33 ± 26.02a156.67 ± 26.02a,b93.33 ± 26.02b88.33 ± 26.02b
May-18130.67 ± 26.02a76.67 ± 26.02a,b49.33 ± 26.02b25 ± 26.02b
AphelenchoidesApheFFApr-1733.33 ± 9.8126.67 ± 9.8148.33 ± 9.8127.67 ± 9.81
Jun-1729.33 ± 9.8120.33 ± 9.8112 ± 9.8111.33 ± 9.81
Sep-1736 ± 9.8148 ± 9.8118 ± 9.8116.67 ± 9.81
Nov-1717 ± 9.8127 ± 9.8116.33 ± 9.8121.33 ± 9.81
Jan-1825.33 ± 9.819.33 ± 9.819.67 ± 9.8116.33 ± 9.81
May-1815 ± 9.815.67 ± 9.8123.33 ± 9.8116.67 ± 9.81
DitylenchusDityFFApr-170 ± 5.130 ± 5.130 ± 5.130 ± 5.13
Jun-1716.67 ± 5.132.33 ± 5.135 ± 5.135 ± 5.13
Sep-1724.67 ± 5.134.33 ± 5.1315.33 ± 5.1313.33 ± 5.13
Nov-1721.33 ± 5.134.33 ± 5.1310.67 ± 5.1326.33 ± 5.13
Jan-1828 ± 5.139 ± 5.1319.67 ± 5.1313.67 ± 5.13
May-1824.33 ± 5.134.33 ± 5.139.67 ± 5.138.67 ± 5.13
DiphtherophoraDiphFFApr-170 ± 3.540 ± 3.540 ± 3.540 ± 3.54
Jun-1713.33 ± 3.549 ± 3.540 ± 3.545 ± 3.54
Sep-171.67 ± 3.548 ± 3.541.33 ± 3.543.67 ± 3.54
Nov-176.67 ± 3.545 ± 3.544 ± 3.542 ± 3.54
Jan-182.33 ± 3.541 ± 3.540 ± 3.540.67 ± 3.54
May-182.67 ± 3.544.33 ± 3.540.67 ± 3.542.33 ± 3.54
MeloidogyneMeloPFApr-17126.33 ± 31.95191.33 ± 31.95135 ± 31.95104.33 ± 31.95
Jun-17165.33 ± 31.95104.33 ± 31.9546.33 ± 31.9540.33 ± 31.95
Sep-1766.67 ± 31.9597 ± 31.9576 ± 31.9533.67 ± 31.95
Nov-1747.33 ± 31.9558.67 ± 31.9551.67 ± 31.9555 ± 31.95
Jan-1829.67 ± 31.9542 ± 31.9510.33 ± 31.9516.33 ± 31.95
May-18135.33 ± 31.95140.67 ± 31.95190.67 ± 31.95114.33 ± 31.95
XenocriconemellaXenoPFApr-1716 ± 26.898 ± 26.896.33 ± 26.8929.33 ± 26.89
Jun-1729 ± 26.8930.67 ± 26.899 ± 26.8940.67 ± 26.89
Sep-1763.33 ± 26.8941.67 ± 26.8916 ± 26.8992 ± 26.89
Nov-1795 ± 26.89112 ± 26.8938 ± 26.8980.67 ± 26.89
Jan-1857.67 ± 26.89108.67 ± 26.8916.33 ± 26.8993.67 ± 26.89
May-1818 ± 26.8946.67 ± 26.8910 ± 26.8947.33 ± 26.89
GracilacusGracPFApr-1711 ± 22.1814 ± 22.188.67 ± 22.1812.67 ± 22.18
Jun-1719.67 ± 22.1813.67 ± 22.182 ± 22.1812.67 ± 22.18
Sep-1724 ± 22.1877 ± 22.1817.33 ± 22.1828.33 ± 22.18
Nov-1758.67 ± 22.1864 ± 22.1821.67 ± 22.1872 ± 22.18
Jan-1849 ± 22.1842.33 ± 22.1811 ± 22.1814.67 ± 22.18
May-1828.33 ± 22.184.33 ± 22.184.67 ± 22.183.67 ± 22.18
HelicotylenchusHeliPFApr-176.67 ± 18.127.67 ± 18.122.67 ± 18.121.33 ± 18.12
Jun-1720.67 ± 18.128.67 ± 18.122.33 ± 18.127.33 ± 18.12
Sep-176.67 ± 18.1274.67 ± 18.121 ± 18.122 ± 18.12
Nov-1756.67 ± 18.126 ± 18.121 ± 18.123 ± 18.12
Jan-1823.33 ± 18.122.33 ± 18.120.67 ± 18.121 ± 18.12
May-1822.33 ± 18.123.67 ± 18.120 ± 18.123.67 ± 18.12
BoleodorusBolePFApr-170 ± 3.850 ± 3.850 ± 3.850 ± 3.85
Jun-1710 ± 3.8510.67 ± 3.857.33 ± 3.856.67 ± 3.85
Sep-1713.33 ± 3.851 ± 3.8510.33 ± 3.856 ± 3.85
Nov-174 ± 3.8514 ± 3.8511.33 ± 3.851 ± 3.85
Jan-186.33 ± 3.850 ± 3.850 ± 3.850 ± 3.85
May-1812.67 ± 3.85a3 ± 3.85b0 ± 3.85b0 ± 3.85b
EcphyadophoraEcphPFApr-171 ± 1.230 ± 1.230 ± 1.230 ± 1.23
Jun-170 ± 1.233.33 ± 1.231.33 ± 1.230.67 ± 1.23
Sep-175.33 ± 1.230 ± 1.230 ± 1.230 ± 1.23
Nov-172.33 ± 1.231 ± 1.231 ± 1.231.67 ± 1.23
Jan-186.67 ± 1.230 ± 1.233.33 ± 1.230 ± 1.23
May-181.33 ± 1.230 ± 1.231.67 ± 1.231 ± 1.23
ClarkusClakPRApr-170 ± 2.130.67 ± 2.133.67 ± 2.130 ± 2.13
Jun-173 ± 2.132.33 ± 2.130.67 ± 2.130 ± 2.13
Sep-172.67 ± 2.131.67 ± 2.134 ± 2.130 ± 2.13
Nov-173.33 ± 2.136.67 ± 2.137.67 ± 2.133.67 ± 2.13
Jan-183.33 ± 2.130 ± 2.131.33 ± 2.130 ± 2.13
May-185.67 ± 2.13a1.67 ± 2.13a,b0 ± 2.13b0 ± 2.13b
TripylaTripPRApr-170 ± 1.930 ± 1.930 ± 1.930 ± 1.93
Jun-171.67 ± 1.931.33 ± 1.930.67 ± 1.930.67 ± 1.93
Sep-173.67 ± 1.932.33 ± 1.930 ± 1.930 ± 1.93
Nov-175 ± 1.935.33 ± 1.932 ± 1.930 ± 1.93
Jan-180 ± 1.930 ± 1.930 ± 1.930 ± 1.93
May-185 ± 1.93a2.33 ± 1.93a,b0 ± 1.93b0 ± 1.93b
DorylaimidaDoryOMApr-173.67 ± 3.337.67 ± 3.330 ± 3.3314.33 ± 3.33
Jun-170 ± 3.330 ± 3.330.67 ± 3.330.67 ± 3.33
Sep-173.33 ± 3.335.33 ± 3.334.33 ± 3.3310.67 ± 3.33
Nov-1711.67 ± 3.3313.67 ± 3.332.67 ± 3.335.33 ± 3.33
Jan-182.33 ± 3.330 ± 3.330 ± 3.330 ± 3.33
May-188.67 ± 3.33a7.33 ± 3.33a,b0 ± 3.33b0 ± 3.33b
AporcelaimellusAporOMApr-170 ± 20.67 ± 20 ± 20 ± 2
Jun-174.67 ± 22.33 ± 21.33 ± 21.33 ± 2
Sep-173 ± 22.33 ± 23.67 ± 22 ± 2
Nov-174 ± 27.33 ± 25.67 ± 23.67 ± 2
Jan-184 ± 22.33 ± 22 ± 20 ± 2
May-186 ± 2a1.67 ± 2b0 ± 2b0 ± 2b

[i] Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey-LSD test).

OM, omnivores; PF, plant feeders; PR, predators; R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Table S2

Abundance and richness of nematode trophic groups per 100 cm3 of soil in different treatments: control, SLR, R2M, and R2W at all sampling times. (mean ± pooled SE, n = 5).

Trophic groupTimeControlSLRR2MR2W
Abundance
BFApr-17274.33 ± 54.05212.67 ± 54.05264.67 ± 54.05180 ± 54.05
Jun-17305.33 ± 54.05191.33 ± 54.05135 ± 54.05145 ± 54.05
Sep-17318.67 ± 54.05311.33 ± 54.05212.67 ± 54.05154 ± 54.05
Nov-17206 ± 54.05220.67 ± 54.05183 ± 54.0597 ± 54.05
Jan-18195.67 ± 54.05130 ± 54.0573.67 ± 54.0566.33 ± 54.05
May-18257.67 ± 54.05a174 ± 54.05a,b125.67 ± 54.05a,b50 ± 54.05b
FFApr-1788.33 ± 32.4779.67 ± 32.47114 ± 32.47141.33 ± 32.47
Jun-17218.33 ± 32.47143.67 ± 32.4792.67 ± 32.47116.33 ± 32.47
Sep-17181 ± 32.47264 ± 32.47167 ± 32.47157.33 ± 32.47
Nov-17158.67 ± 32.47169.67 ± 32.47173.67 ± 32.47114.67 ± 32.47
Jan-18249 ± 32.47a175.33 ± 32.47a,b122.67 ± 32.47b119.33 ± 32.47b
May-18189.67 ± 32.47a100 ± 32.47a,b84.33 ± 32.47a,b53.33 ± 32.47b
PPApr-17170 ± 51.02225.33 ± 51.02153 ± 51.02148.67 ± 51.02
Jun-17244.33 ± 51.02171.67 ± 51.0268.67 ± 51.02109.33 ± 51.02
Sep-17186.33 ± 51.02294 ± 51.02122.67 ± 51.02163.67 ± 51.02
Nov-17271 ± 51.02259.67 ± 51.02134 ± 51.02216.67 ± 51.02
Jan-18175 ± 51.02196 ± 51.0244.67 ± 51.02126.67 ± 51.02
May-18238.33 ± 51.02207.67 ± 51.02208 ± 51.02169.67 ± 51.02
PRApr-170 ± 3.750.67 ± 3.753.67 ± 3.754.33 ± 3.75
Jun-174.67 ± 3.755 ± 3.753.67 ± 3.750.67 ± 3.75
Sep-177.67 ± 3.754 ± 3.755 ± 3.752.33 ± 3.75
Nov-1711 ± 3.7514 ± 3.7517 ± 3.754.67 ± 3.75
Jan-183.33 ± 3.750 ± 3.752 ± 3.750 ± 3.75
May-1813.33 ± 3.75a5.33 ± 3.75a,b0 ± 3.75b0 ± 3.75b
OMApr-173.67 ± 7.668.67 ± 7.660 ± 7.6614.33 ± 7.66
Jun-176.33 ± 7.662.33 ± 7.662 ± 7.665.33 ± 7.66
Sep-177.33 ± 7.667.67 ± 7.669.33 ± 7.6612.67 ± 7.66
Nov-1718.33 ± 7.6623.67 ± 7.669.67 ± 7.6613 ± 7.66
Jan-188.33 ± 7.662.33 ± 7.662.67 ± 7.660 ± 7.66
May-1848.67 ± 7.66a20.33 ± 7.66a,b0.67 ± 7.66b0 ± 7.66b
Richness
BFApr-177 ± 0.966.67 ± 0.967.33 ± 0.966 ± 0.96
Jun-177.67 ± 0.968 ± 0.968 ± 0.969 ± 0.96
Sep-1710.33 ± 0.969.67 ± 0.969.33 ± 0.968.33 ± 0.96
Nov-1711 ± 0.969 ± 0.967 ± 0.967.67 ± 0.96
Jan-1810.67 ± 0.96a9 ± 0.96a,b8 ± 0.96a,b6.33 ± 0.96b
May-1810.33 ± 0.96a8.67 ± 0.96a7 ± 0.96a,b4.67 ± 0.96b
FFApr-172 ± 0.412 ± 0.412 ± 0.411.67 ± 0.41
Jun-173 ± 0.413 ± 0.412.67 ± 0.414 ± 0.41
Sep-174 ± 0.414 ± 0.413.33 ± 0.413.67 ± 0.41
Nov-175 ± 0.414 ± 0.413.67 ± 0.413.67 ± 0.41
Jan-184 ± 0.413.33 ± 0.413 ± 0.413.33 ± 0.41
May-184 ± 0.414 ± 0.414 ± 0.413.67 ± 0.41
PPApr-174.33 ± 0.83 ± 0.83.33 ± 0.83.33 ± 0.8
Jun-174.33 ± 0.85 ± 0.84.33 ± 0.84 ± 0.8
Sep-175.33 ± 0.84.67 ± 0.84.33 ± 0.84.33 ± 0.8
Nov-176.33 ± 0.85.33 ± 0.85.33 ± 0.85.67 ± 0.8
Jan-186 ± 0.83.67 ± 0.84.33 ± 0.83.33 ± 0.8
May-185.67 ± 0.84.33 ± 0.83 ± 0.83.33 ± 0.8
PRApr-170 ± 0.450.33 ± 0.450.33 ± 0.450.33 ± 0.45
Jun-171 ± 0.451 ± 0.451.33 ± 0.450.33 ± 0.45
Sep-171.67 ± 0.450.67 ± 0.451 ± 0.450.33 ± 0.45
Nov-172 ± 0.452 ± 0.452.67 ± 0.451 ± 0.45
Jan-180.33 ± 0.450 ± 0.451 ± 0.450 ± 0.45
May-181.33 ± 0.45a,b1.67 ± 0.45a0 ± 0.45b0 ± 0.45b
OMApr-170.67 ± 0.421 ± 0.420 ± 0.420.67 ± 0.42
Jun-171 ± 0.420.33 ± 0.420.67 ± 0.422 ± 0.42
Sep-172 ± 0.420.67 ± 0.421 ± 0.421.33 ± 0.42
Nov-172.67 ± 0.423.33 ± 0.422 ± 0.423 ± 0.42
Jan-181.67 ± 0.420.33 ± 0.421 ± 0.420 ± 0.42
May-183.33 ± 0.42a3 ± 0.42a0.33 ± 0.42b0 ± 0.42b

[i] Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey–LSD test).

BF, bacterial feeders; FF, fungal feeders; PP, plant feeders; PR, predators; OM, omnivores; R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Table S3

Abundance and richness of nematode c-p classes per 100 cm3 of soil in different treatments: control, SLR, R2M, and R2W at all sampling times. (mean ± SE, n = 5).

c-p classesTimeControlSLRR2MR2W
Abundance
c-p 1Apr-17115.67 ± 34.697 ± 34.6179.33 ± 34.696.67 ± 34.6
c-p 1Jun-17149.33 ± 34.657 ± 34.657 ± 34.665 ± 34.6
c-p 1Sep-17137 ± 34.6123.67 ± 34.694.33 ± 34.631 ± 34.6
c-p 1Nov-1732.33 ± 34.646.67 ± 34.662.33 ± 34.620.67 ± 34.6
c-p 1Jan-1825.33 ± 34.632.67 ± 34.617.67 ± 34.623.33 ± 34.6
c-p 1May-1851 ± 34.635 ± 34.633.33 ± 34.622 ± 34.6
c-p 2Apr-17258.33 ± 51.94210 ± 51.94202.33 ± 51.94235.67 ± 51.94
c-p 2Jun-17361 ± 51.94262.33 ± 51.94168.67 ± 51.94197.67 ± 51.94
c-p 2Sep-17332.67 ± 51.94461.33 ± 51.94268.67 ± 51.94251.33 ± 51.94
c-p 2Nov-17304.67 ± 51.94295.33 ± 51.94263 ± 51.94233.33 ± 51.94
c-p 2Jan-18432.33 ± 51.94a283.67 ± 51.94a,b187.67 ± 51.94b172 ± 51.94b
c-p 2May-18359.67 ± 51.94a158.33 ± 51.94a,b165 ± 51.94b79 ± 51.94b
c-p 3Apr-17158.67 ± 53.65211 ± 53.65150 ± 53.65137.33 ± 53.65
c-p 3Jun-17249.33 ± 53.65183 ± 53.6565 ± 53.65107.33 ± 53.65
c-p 3Sep-17184 ± 53.65272.67 ± 53.65119 ± 53.65176 ± 53.65
c-p 3Nov-17260.33 ± 53.65228.67 ± 53.65121.33 ± 53.65155 ± 53.65
c-p 3Jan-18148 ± 53.65176.33 ± 53.6534.67 ± 53.65114 ± 53.65
c-p 3May-18208 ± 53.65229.67 ± 53.65212 ± 53.65171.67 ± 53.65
c-p 4Apr-173.67 ± 11.238.67 ± 11.233.67 ± 11.2318.67 ± 11.23
c-p 4Jun-1715 ± 11.239 ± 11.2310 ± 11.234.67 ± 11.23
c-p 4Sep-1744 ± 11.2321.67 ± 11.2330.33 ± 11.2329.33 ± 11.23
c-p 4Nov-1756.33 ± 11.23105.33 ± 11.2361 ± 11.2330.67 ± 11.23
c-p 4Jan-1819.67 ± 11.238 ± 11.233.33 ± 11.233 ± 11.23
c-p 4May-1849 ± 11.23a54 ± 11.23a7.67 ± 11.23b0 ± 11.23b
c-p 5Apr-170 ± 6.10.67 ± 6.10 ± 6.10 ± 6.1
c-p 5Jun-174.67 ± 6.12.33 ± 6.11.33 ± 6.11.33 ± 6.1
c-p 5Sep-173 ± 6.12.33 ± 6.13.67 ± 6.12 ± 6.1
c-p 5Nov-1711.67 ± 6.111.67 ± 6.19 ± 6.15.33 ± 6.1
c-p 5Jan-186.33 ± 6.13 ± 6.12.67 ± 6.10 ± 6.1
c-p 5May-1832 ± 6.1a10.33 ± 6.1a,b0.67 ± 6.1b0 ± 6.1b
Richness
c-p 1Apr-171 ± 0.331.33 ± 0.331.33 ± 0.331 ± 0.33
c-p 1Jun-171.33 ± 0.331 ± 0.331.33 ± 0.332 ± 0.33
c-p 1Sep-171.67 ± 0.331.33 ± 0.331.33 ± 0.331.33 ± 0.33
c-p 1Nov-171.67 ± 0.331 ± 0.331.33 ± 0.331 ± 0.33
c-p 1Jan-182 ± 0.332 ± 0.331.67 ± 0.331 ± 0.33
c-p 1May-181.67 ± 0.331.33 ± 0.331 ± 0.331.33 ± 0.33
c-p 2Apr-179 ± 0.877.67 ± 0.877.67 ± 0.877 ± 0.87
c-p 2Jun-179 ± 0.8710.67 ± 0.879 ± 0.8710.67 ± 0.87
c-p 2Sep-1712 ± 0.879 ± 0.879.67 ± 0.879 ± 0.87
c-p 2Nov-1711.67 ± 0.879.67 ± 0.879 ± 0.879.67 ± 0.87
c-p 2Jan-1811.33 ± 0.87a8.33 ± 0.87a,b9.33 ± 0.87a,b7.67 ± 0.87b
c-p 2May-1812 ± 0.87a9 ± 0.87a,b8.33 ± 0.87b6.33 ± 0.87b
c-p 3Apr-173.33 ± 0.812.67 ± 0.813.67 ± 0.813 ± 0.81
c-p 3Jun-174.33 ± 0.814.33 ± 0.814 ± 0.814.33 ± 0.81
c-p 3Sep-175 ± 0.817 ± 0.815 ± 0.815 ± 0.81
c-p 3Nov-177 ± 0.815.33 ± 0.814.67 ± 0.814 ± 0.81
c-p 3Jan-185 ± 0.814.33 ± 0.813.67 ± 0.813.67 ± 0.81
c-p 3May-184.67 ± 0.815.33 ± 0.813.67 ± 0.814 ± 0.81
c-p 4Apr-170.67 ± 0.511 ± 0.510.33 ± 0.511 ± 0.51
c-p 4Jun-171.67 ± 0.511 ± 0.512.33 ± 0.511.67 ± 0.51
c-p 4Sep-174 ± 0.512 ± 0.512.67 ± 0.512 ± 0.51
c-p 4Nov-174.67 ± 0.515.67 ± 0.514 ± 0.515 ± 0.51
c-p 4Jan-183 ± 0.51a1 ± 0.51a,b1.67 ± 0.51a,b0.67 ± 0.51b
c-p 4May-185 ± 0.51a4.67 ± 0.51a1 ± 0.51b0 ± 0.51b
c-p 5Apr-170 ± 0.380.33 ± 0.380 ± 0.380 ± 0.38
c-p 5Jun-170.67 ± 0.380.33 ± 0.380.33 ± 0.380.67 ± 0.38
c-p 5Sep-170.67 ± 0.380.33 ± 0.380.33 ± 0.380.67 ± 0.38
c-p 5Nov-172 ± 0.382 ± 0.381.67 ± 0.381.33 ± 0.38
c-p 5Jan-181.33 ± 0.380.67 ± 0.381 ± 0.380 ± 0.38
c-p 5May-181.33 ± 0.381.33 ± 0.380.33 ± 0.380 ± 0.38

[i] Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey–LSD test).

R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; SLR, surface litter removed.

Table S4

Nematode ecological indices in different treatments: control, SLR, R2M, and R2W at all sampling times. (mean ± pooled SE, n = 5).

IndicesTimeControlSLRR2MR2W
λApr-170.15 ± 0.030.2 ± 0.030.23 ± 0.030.2 ± 0.03
Jun-170.16 ± 0.030.14 ± 0.030.12 ± 0.030.12 ± 0.03
Sep-170.11 ± 0.030.14 ± 0.030.15 ± 0.030.15 ± 0.03
Nov-170.1 ± 0.030.12 ± 0.030.14 ± 0.030.17 ± 0.03
Jan-180.14 ± 0.03a0.19 ± 0.03a,b0.2 ± 0.03a,b0.27 ± 0.03b
May-180.11 ± 0.03a0.17 ± 0.03a,b0.26 ± 0.03b0.24 ± 0.03b
Apr-172.17 ± 0.141.99 ± 0.141.85 ± 0.141.89 ± 0.14
Jun-172.19 ± 0.142.29 ± 0.141.83 ± 0.141.82 ± 0.14
Sep-172.56 ± 0.142.28 ± 0.142.29 ± 0.142.24 ± 0.14
Nov-172.65 ± 0.142.49 ± 0.142.37 ± 0.142.28 ± 0.14
Jan-182.44 ± 0.14a2.07 ± 0.14a,b2.16 ± 0.14a,b1.84 ± 0.14b
May-182.63 ± 0.14a2.27 ± 0.14a,b1.88 ± 0.14b1.82 ± 0.14b
NCRApr-170.72 ± 0.060.69 ± 0.060.69 ± 0.060.58 ± 0.06
Jun-170.58 ± 0.060.57 ± 0.060.58 ± 0.060.55 ± 0.06
Sep-170.61 ± 0.060.53 ± 0.060.56 ± 0.060.49 ± 0.06
Nov-170.56 ± 0.060.57 ± 0.060.5 ± 0.060.46 ± 0.06
Jan-180.43 ± 0.060.46 ± 0.060.36 ± 0.060.38 ± 0.06
May-180.57 ± 0.060.64 ± 0.060.59 ± 0.060.48 ± 0.06
MIApr-171.78 ± 0.121.8 ± 0.141.65 ± 0.31.92 ± 0.29
Jun-171.87 ± 0.282.02 ± 0.141.9 ± 0.21.89 ± 0.13
Sep-172.01 ± 0.061.97 ± 0.092.02 ± 0.172.25 ± 0.13
Nov-172.4 ± 0.352.56 ± 0.312.28 ± 0.122.31 ± 0.09
Jan-182.12 ± 0.05a2.1 ± 0.11a,b2.05 ± 0.12a,b1.92 ± 0.07b
May-182.29 ± 0.16a2.53 ± 0.28a1.96 ± 0.08b1.84 ± 0.14b
PPIApr-172.86 ± 0.082.88 ± 0.192.95 ± 0.052.92 ± 0.09
Jun-172.87 ± 0.12.81 ± 0.092.85 ± 0.122.79 ± 0.18
Sep-172.72 ± 0.12.77 ± 0.332.76 ± 0.052.8 ± 0.21
Nov-172.75 ± 0.122.72 ± 0.082.61 ± 0.212.74 ± 0.36
Jan-182.66 ± 0.242.81 ± 0.182.61 ± 0.072.86 ± 0.15
May-182.76 ± 0.122.95 ± 0.042.96 ± 0.042.97 ± 0.05
BIApr-1731.84 ± 3.4828.58 ± 3.825.51 ± 7.9731.75 ± 4.78
Jun-1726.42 ± 3.833.21 ± 3.3330.42 ± 5.3330.32 ± 5.23
Sep-1724.3 ± 3.4828.84 ± 4.2624.66 ± 3.7129.98 ± 1.22
Nov-1727.25 ± 4.2618.71 ± 1.2424.36 ± 4.430.1 ± 1.72
Jan-1841.83 ± 1.1439.89 ± 1.1241.87 ± 1.9540.39 ± 2.22
May-1831.21 ± 3.5620.41 ± 3.9935.71 ± 1.9932.51 ± 0.24
EIApr-1766.2 ± 4.0368.84 ± 4.2572.27 ± 9.5160.4 ± 9.64
Jun-1768.42 ± 5.7959.54 ± 2.1564.4 ± 7.3365.84 ± 5.59
Sep-1769.49 ± 3.3165.51 ± 5.0969.57 ± 2.5455.23 ± 2.49
Nov-1752.55 ± 2.3059.96 ± 5.1363.86 ± 5.1753.52 ± 3.57
Jan-1848.21 ± 1.01a50.34 ± 3.83a,b52.04 ± 1.82a,b57.65 ± 2.15b
May-1852.87 ± 2.16a59.36 ± 3.97a,b58.99 ± 2.40a,b65.12 ± 1.81b
SIApr-1714.27 ± 1.3522.25 ± 6.912.07 ± 4.7925.55 ± 7.8
Jun-1731.28 ± 4.6133.43 ± 9.5829.57 ± 2.7528.73 ± 4.57
Sep-1746.73 ± 6.637.35 ± 3.6943.58 ± 11.2751.35 ± 3.55
Nov-1757.72 ± 10.0572.03 ± 3.6758.43 ± 7.4153.67 ± 1.65
Jan-1831.26 ± 2.8a30.91 ± 3.68a21.91 ± 6.05a,b10.53 ± 2.01b
May-1851.8 ± 6.82a70.23 ± 6.86a25.76 ± 4.36b12.89 ± 8.01b
CIApr-1721.48 ± 4.7422.72 ± 7.8724.39 ± 9.9338.52 ± 9.49
Jun-1731.69 ± 8.9638.64 ± 2.7538.6 ± 13.9136.74 ± 12.31
Sep-1728.38 ± 5.1537.83 ± 8.5730.54 ± 2.2359.49 ± 7.66
Nov-1756.33 ± 6.7852.89 ± 10.0445.06 ± 7.5262.05 ± 7.36
Jan-1871.5 ± 3.0665.09 ± 5.0667.81 ± 3.8755.13 ± 9.72
May-1848.61 ± 3.5642.47 ± 8.4037.76 ± 1.8336.75 ± 2.08
efootApr-17169.74 ± 65141.14 ± 39.47260.54 ± 90.16145.4 ± 72.04
Jun-17224.54 ± 68.3288.81 ± 22.3386.28 ± 28.1396.08 ± 30.17
Sep-17206.41 ± 56.66188.21 ± 53.38144.31 ± 2.4653.65 ± 16.03
Nov-1755 ± 13.9575.96 ± 26.9397.97 ± 28.8139.16 ± 9.96
Jan-1849.85 ± 2.5149.46 ± 15.8531.49 ± 6.7641.54 ± 6.38
May-1879.35 ± 16.03a53.59 ± 14.81a,b53.52 ± 4.22a,b34.6 ± 3.36b
sfootApr-179.18 ± 3.4818.84 ± 10.553.97 ± 2.4833.54 ± 14.29
Jun-1720.55 ± 6.9915 ± 6.668.13 ± 0.899.7 ± 2.07
Sep-1731.39 ± 10.529.61 ± 8.0727.88 ± 9.7737.59 ± 11.4
Nov-1761.17 ± 14.2979.08 ± 16.4342.2 ± 10.4931.76 ± 8.49
Jan-1824.22 ± 4.3a8.58 ± 2.8a,b6.69 ± 1.86b0.9 ± 0.2b
May-1862.77 ± 21.42a43.13 ± 4.79a3.55 ± 0.76b0.79 ± 0.48b

[i] Letters indicate significant differences among treatments at each sampling time at P < 0.05 (Tukey–LSD test).

λ, Simpson index; H´, Shannon–Weiner index.

BI, basal index; CI, channel index, efoot, enrichment footprint; EI, enrichment index; MI, maturity index; NCR, nematode channel ratio; PPI, plant parasitic index; R2M, rototill for every 2 mon; R2W, rototill for every 2 wk; sfoot, structure footprint; SI, structure index; SLR, surface litter removed.

Table S5

Similarity percentage analysis of the nematode communities between treatments: control, surface litter removed (SLR), rototill for every two months (R2M), and rototill for every two weeks (R2W) at all sampling times.

Av.DissSDDiss/SDAv.AbundAv.AbundContrib (%)cumsum (%)p
Apr-17
Control vs SLRAverage dissimilarity = 39.35
Meloidogyne9.669.121.06126.33191.3324.5424.540.195
Rhabditidae7.984.821.66115.6796.0020.2944.830.952
Acrobeloides4.942.921.6946.3353.6712.5557.380.076
Plectus3.412.701.2755.6726.338.6866.060.162
Filenchus2.371.961.2155.3352.336.0272.080.845
Gracilacus1.811.910.9411.0014.004.5976.670.345
Aphelenchoides1.440.901.5933.3326.673.6680.330.939
Xenocriconemella1.361.011.3416.008.003.4483.770.805
Pseudacrobeles1.180.751.5820.0022.003.0086.770.593
Tylocephalus0.980.811.2216.674.672.4989.260.395
Dorylaimida0.881.010.883.677.672.2591.510.639
Helicotylenchus0.800.920.876.677.672.0393.540.207
Prismatolaimus0.640.521.247.002.671.6395.170.091
Acrobeles0.580.660.886.672.671.4896.650.29
Ceratoplectus0.450.331.383.002.671.1497.790.362
Teratocephalus0.430.460.933.001.671.0998.880.372
Cervidellus0.130.210.641.000.000.3499.220.577
Ecphyadophora0.130.210.641.000.000.3399.550.213
Aporcelaimellus0.090.140.630.000.670.2399.780.2
Clarkus0.090.140.630.000.670.22100.000.635
Alaimus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Diplogasteridae0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
Control vs R2MAverage dissimilarity = 36.73
Rhabditidae12.789.121.40115.67177.6734.7834.780.215
Meloidogyne6.131.673.66126.33135.0016.6851.460.533
Acrobeloides3.612.741.3246.3324.009.8461.300.446
Plectus2.590.982.6555.6729.337.0468.340.574
Aphelenchoides2.191.961.1233.3348.335.9674.300.619
Filenchus2.091.871.1255.3365.675.6879.980.93
Xenocriconemella1.170.951.2416.006.333.1983.170.872
Tylocephalus0.970.711.3716.679.672.6385.800.439
Pseudacrobeles0.870.441.9920.0011.672.3688.160.927
Gracilacus0.740.401.8611.008.672.0190.170.834
Helicotylenchus0.620.501.246.672.671.6991.860.598
Acrobeles0.550.630.876.671.671.4993.350.4
Prismatolaimus0.540.351.547.002.331.4894.830.289
Ceratoplectus0.420.450.933.002.331.1495.970.438
Teratocephalus0.420.450.933.002.331.1597.120.382
Clarkus0.320.500.650.003.670.8898.000.352
Dorylaimida0.310.241.293.670.000.8598.850.915
Diplogasteridae0.150.240.650.001.670.4299.270.298
Cervidellus0.140.180.821.001.000.3999.660.455
Ecphyadophora0.120.190.651.000.000.34100.000.279
Alaimus0.000.00NaN0.000.000.00100.001
Aporcelaimellus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
Control vs R2WAverage dissimilarity = 42.92
Rhabditidae9.326.321.47115.6796.6721.7221.720.822
Filenchus6.445.871.1055.33113.6715.0136.730.205
Meloidogyne5.143.071.68126.33104.3311.9848.710.611
Plectus4.562.591.7655.6730.3310.6259.330.009
Acrobeloides4.392.941.4946.3330.0010.2469.570.177
Xenocriconemella2.431.671.4516.0029.335.6675.230.082
Aphelenchoides2.411.501.6033.3327.675.6080.830.481
Pseudacrobeles1.510.981.5420.0011.333.5184.340.207
Gracilacus1.391.381.0111.0012.673.2587.590.644
Dorylaimida1.310.921.423.6714.333.0590.640.166
Tylocephalus1.300.861.5116.675.003.0293.660.044
Acrobeles0.550.690.796.671.331.2894.940.395
Helicotylenchus0.550.690.796.671.331.2796.210.723
Prismatolaimus0.490.391.267.002.671.1497.350.419
Ceratoplectus0.430.520.833.001.001.0198.360.403
Teratocephalus0.410.640.643.000.000.9599.310.385
Cervidellus0.160.200.791.001.000.3799.680.409
Ecphyadophora0.140.210.641.000.000.32100.000.141
Alaimus0.000.00NaN0.000.000.00100.001
Aporcelaimellus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Clarkus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Diplogasteridae0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
SLR vs R2MAverage dissimilarity = 38.89
Rhabditidae13.087.851.6796.00177.6733.6233.620.218
Meloidogyne8.806.861.28191.33135.0022.6456.260.366
Acrobeloides2.802.101.3353.6724.007.2063.460.723
Aphelenchoides2.622.191.1926.6748.336.7470.200.356
Filenchus2.331.671.3952.3365.675.9976.190.871
Gracilacus1.741.641.0614.008.674.4780.660.406
Plectus1.401.191.1826.3329.333.6084.260.986
Pseudacrobeles1.210.651.8722.0011.673.1287.380.553
Dorylaimida0.841.110.767.670.002.1789.550.682
Xenocriconemella0.730.611.208.006.331.8791.420.962
Helicotylenchus0.700.621.147.672.671.8193.230.395
Tylocephalus0.620.292.114.679.671.5994.820.811
Clarkus0.360.430.840.673.670.9395.750.244
Prismatolaimus0.360.440.812.672.330.9296.670.752
Ceratoplectus0.340.231.512.672.330.8897.550.634
Teratocephalus0.320.350.941.672.330.8398.380.609
Acrobeles0.270.280.952.671.670.6999.070.7
Diplogasteridae0.150.240.650.001.670.3999.460.298
Cervidellus0.130.200.640.001.000.3399.790.611
Aporcelaimellus0.080.130.650.670.000.21100.000.286
Alaimus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Ecphyadophora0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
SLR vs R2WAverage dissimilarity = 42.38
Rhabditidae9.055.141.7696.0096.6721.3621.360.859
Meloidogyne8.479.360.91191.33104.3320.0041.360.416
Filenchus6.785.841.1652.33113.6716.0057.360.144
Acrobeloides3.022.281.3353.6730.007.1364.490.67
Plectus2.671.921.3926.3330.336.3070.790.552
Xenocriconemella2.371.451.648.0029.335.6176.400.133
Aphelenchoides2.321.201.9326.6727.675.4781.870.547
Gracilacus1.991.851.0714.0012.674.6986.560.231
Pseudacrobeles1.641.141.4422.0011.333.8890.440.09
Dorylaimida1.321.001.327.6714.333.1393.570.175
Helicotylenchus0.640.830.777.671.331.5095.070.545
Tylocephalus0.620.371.684.675.001.4696.530.814
Prismatolaimus0.390.271.462.672.670.9397.460.648
Ceratoplectus0.280.261.062.671.000.6598.110.783
Acrobeles0.250.280.902.671.330.6098.710.697
Teratocephalus0.230.360.641.670.000.5599.260.77
Cervidellus0.130.210.640.001.000.3099.560.592
Aporcelaimellus0.090.140.640.670.000.2299.780.144
Clarkus0.090.140.640.670.000.22100.000.585
Alaimus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Diplogasteridae0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Ecphyadophora0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
R2M vs R2WAverage dissimilarity = 39.39
Rhabditidae13.9610.261.36177.6796.6735.4435.440.096
Filenchus5.995.231.1565.67113.6715.2150.650.296
Aphelenchoides3.292.561.2948.3327.678.3659.010.116
Meloidogyne2.971.581.88135.00104.337.5366.540.929
Plectus2.940.714.1529.3330.337.4573.990.381
Xenocriconemella2.261.661.366.3329.335.7379.720.152
Gracilacus1.361.161.178.6712.673.4683.180.69
Dorylaimida1.341.041.290.0014.333.3986.570.161
Acrobeloides1.321.480.8924.0030.003.3589.920.969
Pseudacrobeles1.120.611.8211.6711.332.8392.750.701
Tylocephalus0.770.551.399.675.001.9694.710.592
Prismatolaimus0.360.241.502.332.670.9095.610.755
Clarkus0.330.510.653.670.000.8596.460.315
Ceratoplectus0.320.370.872.331.000.8297.280.66
Teratocephalus0.300.470.642.330.000.7798.050.623
Helicotylenchus0.270.231.162.671.330.6898.730.816
Acrobeles0.190.220.861.671.330.4999.220.822
Diplogasteridae0.160.240.651.670.000.4099.620.212
Cervidellus0.150.180.821.001.000.38100.000.419
Alaimus0.000.00NaN0.000.000.00100.001
Aporcelaimellus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Diphtherophora0.000.00NaN0.000.000.00100.001
Ditylenchus0.000.00NaN0.000.000.00100.001
Ecphyadophora0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
Jun-17
Control vs SLRAverage dissimilarity = 39.91
Rhabditidae7.606.681.14147.6757.0019.0519.050.418
Filenchus6.404.251.51158.67111.6716.0335.080.448
Meloidogyne5.975.021.19165.33104.3314.9550.030.593
Plectus2.531.371.8472.3340.006.3456.370.74
Xenocriconemella2.051.531.3429.0030.675.1461.510.851
Prismatolaimus1.841.481.2519.0028.004.6166.120.503
Aphelenchoides1.721.041.6629.3320.334.3270.440.311
Acrobeloides1.440.931.5418.6727.003.6074.040.813
Helicotylenchus1.391.211.1620.678.673.5077.540.472
Diphtherophora1.281.221.0513.339.003.2180.750.425
Ditylenchus1.240.851.4616.672.333.1083.850.085
Pseudacrobeles1.100.761.4318.675.672.7586.600.285
Boleodorus0.980.941.0410.0010.672.4489.040.776
Alaimus0.810.711.1410.335.332.0491.080.515
Gracilacus0.730.800.9119.6713.671.8292.900.918
Ceratoplectus0.710.641.105.0012.331.7794.670.638
Tylocephalus0.400.291.399.677.671.0095.670.833
Acrobeles0.390.201.921.676.330.9796.640.91
Aporcelaimellus0.370.321.164.672.330.9397.570.418
Clarkus0.270.181.453.002.330.6698.230.357
Ecphyadophora0.250.211.200.003.330.6498.870.376
Tripyla0.160.190.871.671.330.4199.280.622
Teratocephalus0.150.230.660.001.670.3999.670.503
Diplogasteridae0.130.200.661.670.000.33100.000.832
Cervidellus0.000.00NaN0.000.000.00100.001
Dorylaimida0.000.00NaN0.000.000.00100.001
Control vs R2MAverage dissimilarity = 53.30
Meloidogyne10.704.702.28165.3346.3320.0720.070.017
Rhabditidae9.067.571.20147.6756.3317.0037.070.191
Filenchus8.886.151.44158.6775.6716.6653.730.046
Plectus5.191.104.7072.3316.339.7463.470.007
Aphelenchoides2.271.311.7329.3312.004.2667.730.014
Xenocriconemella2.181.341.6329.009.004.0971.820.796
Helicotylenchus1.761.211.4520.672.333.3075.120.119
Gracilacus1.661.111.5019.672.003.1278.240.057
Acrobeloides1.531.021.5018.6728.332.8881.120.697
Ditylenchus1.260.891.4216.675.002.3783.490.08
Diphtherophora1.261.900.6713.330.002.3785.860.433
Prismatolaimus1.220.651.8919.006.002.2888.140.643
Pseudacrobeles1.210.851.4318.676.002.2890.420.17
Boleodorus1.020.961.0710.007.331.9292.340.74
Tylocephalus0.810.382.119.670.671.5293.860.123
Alaimus0.790.601.3310.336.331.4995.350.544
Ceratoplectus0.570.441.315.007.331.0796.420.778
Acrobeles0.560.650.871.675.671.0697.480.79
Aporcelaimellus0.400.371.084.671.330.7698.240.281
Clarkus0.270.181.473.000.670.5098.740.356
Diplogasteridae0.180.190.921.670.670.3499.080.709
Tripyla0.180.190.921.670.670.3399.410.535
Ecphyadophora0.130.101.310.001.330.2499.650.841
Teratocephalus0.070.100.660.000.670.1299.770.79
Cervidellus0.060.090.660.000.670.1299.890.745
Dorylaimida0.060.090.660.000.670.11100.000.78
Control vs R2WAverage dissimilarity = 49.23
Meloidogyne10.624.582.32165.3340.3321.5621.560.012
Rhabditidae8.277.161.16147.6761.6716.7938.350.326
Filenchus7.695.451.41158.6794.6715.6253.970.152
Plectus4.561.562.9272.3320.339.2663.230.014
Xenocriconemella3.302.581.2829.0040.676.7169.940.544
Aphelenchoides2.161.331.6229.3311.334.3974.330.034
Helicotylenchus1.551.241.2520.677.333.1477.470.325
Diphtherophora1.331.420.9313.335.002.7080.170.369
Acrobeloides1.280.771.6618.6719.002.5982.760.899
Ditylenchus1.170.761.5416.675.002.3785.130.141
Pseudacrobeles1.140.641.7918.676.672.3287.450.211
Gracilacus1.040.891.1719.6712.672.1289.570.642
Alaimus0.970.891.1010.330.001.9891.550.226
Boleodorus0.900.771.1610.006.671.8293.370.835
Prismatolaimus0.690.491.4019.0012.331.3994.760.981
Acrobeles0.600.561.081.677.671.2295.980.781
Ceratoplectus0.400.351.175.005.330.8296.800.965
Aporcelaimellus0.380.311.204.671.330.7797.570.406
Tylocephalus0.350.321.109.676.330.7198.280.912
Clarkus0.280.211.323.000.000.5698.840.318
Diplogasteridae0.220.191.161.672.670.4599.290.483
Tripyla0.170.180.931.670.670.3499.630.589
Cervidellus0.060.100.660.000.670.1399.760.753
Dorylaimida0.060.100.660.000.670.1399.890.761
Ecphyadophora0.060.080.660.000.670.11100.000.995
Teratocephalus0.000.00NaN0.000.000.00100.001
SLR vs R2MAverage dissimilarity = 40.41
Meloidogyne6.595.331.24104.3346.3316.3016.300.5
Rhabditidae4.873.001.6257.0056.3312.0528.350.798
Filenchus4.783.851.24111.6775.6711.8340.180.8
Xenocriconemella3.152.661.1830.679.007.7947.970.559
Prismatolaimus3.093.081.0028.006.007.6555.620.048
Plectus3.001.701.7740.0016.337.4363.050.447
Acrobeloides2.071.741.1927.0028.335.1468.190.266
Gracilacus1.420.226.6213.672.003.5271.710.192
Boleodorus1.421.351.0510.677.333.5275.230.307
Ceratoplectus1.111.011.1012.337.332.7377.960.139
Diphtherophora1.031.001.039.000.002.5580.510.527
Helicotylenchus1.031.100.938.672.332.5583.060.815
Aphelenchoides1.020.801.2720.3312.002.5185.570.789
Tylocephalus1.000.791.267.670.672.4788.040.02
Acrobeles0.960.481.996.335.672.3890.420.232
Alaimus0.950.462.085.336.332.3692.780.267
Pseudacrobeles0.650.571.155.676.001.6194.390.905
Ditylenchus0.600.551.082.335.001.4895.870.857
Ecphyadophora0.340.231.463.331.330.8496.710.048
Aporcelaimellus0.320.330.972.331.330.7997.500.595
Teratocephalus0.290.340.851.670.670.7198.210.082
Clarkus0.280.310.932.330.670.7198.920.311
Tripyla0.180.180.991.330.670.4499.360.516
Diplogasteridae0.090.140.640.000.670.2399.590.952
Cervidellus0.090.130.650.000.670.2199.800.53
Dorylaimida0.080.120.650.000.670.20100.000.611
SLR vs R2WAverage dissimilarity = 39.48
Meloidogyne6.835.031.36104.3340.3317.3117.310.435
Filenchus5.123.611.42111.6794.6712.9730.280.759
Rhabditidae4.603.001.5457.0061.6711.6541.930.84
Xenocriconemella4.554.091.1130.6740.6711.5253.450.264
Prismatolaimus2.812.431.1628.0012.337.1260.570.132
Plectus2.611.701.5440.0020.336.6267.190.716
Acrobeloides1.831.361.3527.0019.004.6571.840.474
Boleodorus1.281.041.2310.676.673.2475.080.479
Helicotylenchus1.191.340.898.677.333.0078.080.645
Aphelenchoides1.040.841.2320.3311.332.6380.710.738
Ceratoplectus1.031.011.0312.335.332.6183.320.233
Diphtherophora0.900.731.249.005.002.2885.600.611
Gracilacus0.830.481.7213.6712.672.1087.700.858
Pseudacrobeles0.780.701.105.676.671.9689.660.779
Acrobeles0.750.521.446.337.671.9091.560.598
Ditylenchus0.580.501.152.335.001.4793.030.887
Alaimus0.580.870.665.330.001.4794.500.843
Tylocephalus0.420.450.927.676.331.0695.560.785
Ecphyadophora0.350.271.273.330.670.8796.430.035
Aporcelaimellus0.300.221.332.331.330.7697.190.679
Diplogasteridae0.300.251.200.002.670.7497.930.143
Teratocephalus0.250.370.661.670.000.6398.560.191
Clarkus0.220.340.662.330.000.5799.130.566
Tripyla0.170.171.001.330.670.4399.560.589
Cervidellus0.090.130.650.000.670.2299.780.517
Dorylaimida0.090.130.650.000.670.22100.000.45
R2M vs R2WAverage dissimilarity = 35.56
Rhabditidae6.374.681.3656.3361.6717.9117.910.588
Xenocriconemella5.575.650.999.0040.6715.6733.580.066
Filenchus4.674.631.0175.6794.6713.1346.710.842
Acrobeloides2.171.691.2928.3319.006.1152.820.177
Gracilacus1.601.091.472.0012.674.5057.320.077
Plectus1.531.161.3116.3320.334.2961.610.996
Meloidogyne1.421.421.0046.3340.334.0165.620.995
Prismatolaimus1.421.091.316.0012.333.9969.610.552
Boleodorus1.341.131.197.336.673.7773.380.405
Acrobeles1.201.091.105.677.673.3676.740.063
Helicotylenchus1.131.210.942.337.333.1879.920.733
Pseudacrobeles1.010.731.396.006.672.8382.750.446
Alaimus0.980.511.936.330.002.7585.500.239
Ceratoplectus0.890.621.427.335.332.5088.000.382
Tylocephalus0.850.126.830.676.332.3790.370.077
Diphtherophora0.720.641.120.005.002.0292.390.732
Ditylenchus0.690.571.205.005.001.9394.320.803
Aphelenchoides0.590.521.1512.0011.331.6795.990.972
Diplogasteridae0.350.251.410.672.670.9896.970.035
Aporcelaimellus0.270.181.481.331.330.7697.730.771
Ecphyadophora0.170.171.041.330.670.4898.210.651
Tripyla0.140.170.840.670.670.4098.610.689
Cervidellus0.140.170.830.670.670.3999.000.073
Dorylaimida0.140.170.820.670.670.3999.390.09
Clarkus0.110.170.660.670.000.3099.690.934
Teratocephalus0.110.170.660.670.000.31100.000.516
Sep-17
Control vs SLRAverage dissimilarity = 43.89
Filenchus5.623.431.64116.33196.3312.8012.800.039
Rhabditidae5.483.601.52134.67120.0012.4925.290.648
Helicotylenchus4.726.180.766.6774.6710.7436.030.348
Gracilacus4.395.110.8624.0077.0010.0046.030.477
Meloidogyne3.423.530.9766.6797.007.7953.820.622
Plectus2.892.401.2050.0063.006.5860.400.436
Xenocriconemella2.781.861.4963.3341.676.3266.720.878
Aphelenchoides2.141.661.2936.0048.004.8771.590.427
Prismatolaimus1.941.461.3428.3337.674.4376.020.694
Acrobeloides1.511.111.3611.6731.333.4379.450.814
Alaimus1.491.171.2733.6713.003.3982.840.486
Ditylenchus1.340.602.2224.674.333.0585.890.182
Pseudacrobeles0.800.541.4819.338.001.8187.700.479
Boleodorus0.790.164.9713.331.001.8089.500.153
Teratocephalus0.710.621.1412.337.001.6091.100.509
Acrobeles0.690.471.487.6712.331.5892.680.742
Ceratoplectus0.570.421.379.335.331.3093.980.256
Diphtherophora0.410.162.491.678.000.9394.910.245
Dorylaimida0.390.341.133.005.330.8995.800.908
Ecphyadophora0.380.311.235.330.000.8796.670.101
Cervidellus0.290.300.952.333.330.6597.320.438
Diplogasteridae0.280.231.222.673.670.6397.950.192
Tylocephalus0.270.211.305.673.330.6298.570.531
Tripyla0.240.240.993.672.330.5499.110.322
Aporcelaimellus0.230.221.063.002.330.5299.630.78
Clarkus0.160.141.172.671.670.37100.000.745
Control vs R2MAverage dissimilarity = 38.78
Rhabditidae6.471.384.70134.6793.6716.6816.680.314
Xenocriconemella4.563.291.3963.3316.0011.7728.450.456
Meloidogyne3.632.711.3466.6776.009.3537.800.553
Filenchus3.312.501.32116.33133.008.5246.320.613
Plectus2.981.771.6950.0010.677.6954.010.385
Acrobeloides2.192.031.0811.6736.335.6459.650.41
Prismatolaimus2.131.481.4428.3320.675.4965.140.543
Alaimus2.001.581.2633.6720.005.1770.310.106
Aphelenchoides1.760.981.8036.0018.004.5474.850.514
Acrobeles1.080.881.237.6712.332.8077.650.364
Ditylenchus0.990.921.0824.6715.332.5680.210.674
Pseudacrobeles0.990.771.2819.338.672.5482.750.15
Gracilacus0.910.741.2324.0017.332.3485.090.963
Teratocephalus0.880.811.0812.332.332.2787.360.109
Helicotylenchus0.781.090.716.671.002.0089.360.645
Boleodorus0.600.451.3213.3310.331.5590.910.656
Ceratoplectus0.510.351.459.335.001.3192.220.511
Ecphyadophora0.500.411.245.330.001.3093.520.017
Dorylaimida0.480.481.023.004.331.2594.770.812
Aporcelaimellus0.400.351.153.003.671.0395.800.316
Tylocephalus0.380.281.365.671.330.9896.780.089
Clarkus0.300.320.922.674.000.7697.540.364
Cervidellus0.280.350.792.331.000.7298.260.485
Tripyla0.270.221.213.670.000.7098.960.197
Diphtherophora0.210.250.841.671.330.5399.490.962
Diplogasteridae0.200.151.322.670.000.51100.000.556
Control vs R2WAverage dissimilarity = 44.55
Rhabditidae8.505.021.69134.6730.0019.0819.080.035
Xenocriconemella5.123.741.3763.3392.0011.4930.570.376
Meloidogyne3.482.551.3666.6733.677.8238.390.604
Filenchus3.061.871.63116.33123.336.8745.260.719
Prismatolaimus2.862.401.1928.3341.676.4151.670.119
Gracilacus2.851.811.5724.0028.336.4158.080.635
Plectus2.521.801.4150.0017.675.6663.740.526
Acrobeloides2.432.261.0811.6737.675.4569.190.248
Aphelenchoides1.881.051.7936.0016.674.2173.400.504
Alaimus1.851.251.4833.6716.004.1577.550.188
Pseudacrobeles1.650.483.4619.331.003.7081.250.004
Ditylenchus1.480.761.9524.6713.333.3184.560.089
Teratocephalus0.900.841.0712.332.002.0386.590.077
Dorylaimida0.840.651.303.0010.671.8988.480.193
Helicotylenchus0.811.010.806.672.001.8190.290.622
Ceratoplectus0.660.481.379.331.001.4991.780.102
Boleodorus0.630.461.3713.336.001.4293.200.511
Acrobeles0.590.471.267.672.001.3394.530.833
Ecphyadophora0.520.421.245.330.001.1695.690.012
Tylocephalus0.390.281.375.671.000.8796.560.053
Diphtherophora0.320.251.261.673.670.7297.280.719
Cervidellus0.310.122.462.333.000.6997.970.307
Tripyla0.280.231.213.670.000.6298.590.182
Aporcelaimellus0.230.151.533.002.000.5199.100.773
Clarkus0.200.151.332.670.000.4599.550.604
Diplogasteridae0.200.151.332.670.000.45100.000.553
SLR vs R2MAverage dissimilarity = 40.47
Helicotylenchus5.187.140.7374.671.0012.8012.800.154
Gracilacus4.845.830.8377.0017.3311.9524.750.315
Filenchus4.512.831.60196.33133.0011.1535.900.241
Rhabditidae3.613.101.17120.0093.678.9344.830.941
Plectus3.573.341.0763.0010.678.8253.650.114
Meloidogyne2.922.611.1297.0076.007.2060.850.796
Xenocriconemella2.622.341.1241.6716.006.4767.320.903
Aphelenchoides2.162.380.9148.0018.005.3572.670.424
Acrobeloides1.711.091.5731.3336.334.2376.900.755
Prismatolaimus1.581.251.2737.6720.673.9180.810.904
Alaimus1.091.180.9313.0020.002.6983.500.768
Acrobeles1.050.801.3212.3312.332.6186.110.418
Ditylenchus0.900.601.504.3315.332.2288.330.822
Boleodorus0.730.501.471.0010.331.8190.140.249
Pseudacrobeles0.550.361.518.008.671.3591.490.922
Ceratoplectus0.510.212.455.335.001.2692.750.516
Dorylaimida0.490.550.895.334.331.2293.970.816
Diphtherophora0.470.232.048.001.331.1895.150.083
Teratocephalus0.430.202.157.002.331.0696.210.557
Aporcelaimellus0.340.341.002.333.670.8597.060.482
Clarkus0.290.271.081.674.000.7197.770.403
Cervidellus0.260.300.853.331.000.6398.400.649
Diplogasteridae0.230.350.673.670.000.5798.970.381
Tripyla0.210.320.662.330.000.5399.500.443
Tylocephalus0.200.161.233.331.330.50100.000.698
Ecphyadophora0.000.00NaN0.000.000.00100.001
SLR vs R2WAverage dissimilarity = 47.26
Rhabditidae6.434.631.39120.0030.0013.6013.600.278
Gracilacus5.585.421.0377.0028.3311.8125.410.142
Helicotylenchus5.237.210.7374.672.0011.0736.480.126
Meloidogyne5.093.581.4297.0033.6710.7647.240.098
Filenchus5.062.751.84196.33123.3310.7057.940.083
Xenocriconemella4.263.711.1541.6792.009.0166.950.593
Plectus3.233.320.9763.0017.676.8373.780.26
Aphelenchoides2.362.331.0148.0016.675.0078.780.281
Prismatolaimus1.821.441.2637.6741.673.8582.630.724
Acrobeloides1.801.211.4931.3337.673.8186.440.747
Acrobeles0.830.671.2412.332.001.7588.190.582
Ditylenchus0.820.870.954.3313.331.7489.930.909
Dorylaimida0.750.641.185.3310.671.5991.520.426
Pseudacrobeles0.500.431.158.001.001.0692.580.972
Alaimus0.500.451.1113.0016.001.0593.630.972
Teratocephalus0.440.212.087.002.000.9394.560.533
Boleodorus0.430.311.391.006.000.9195.470.969
Ceratoplectus0.400.500.815.331.000.8596.320.763
Diphtherophora0.390.251.578.003.670.8297.140.325
Cervidellus0.320.132.423.333.000.6897.820.258
Aporcelaimellus0.250.211.192.332.000.5398.350.694
Diplogasteridae0.240.350.673.670.000.4998.840.387
Tripyla0.220.330.672.330.000.4799.310.401
Tylocephalus0.210.141.453.331.000.4499.750.635
Clarkus0.120.180.671.670.000.25100.000.92
Ecphyadophora0.000.00NaN0.000.000.00100.001
R2M vs R2WAverage dissimilarity = 39.04
Xenocriconemella7.545.701.3216.0092.0019.3219.320.016
Rhabditidae6.562.402.7393.6730.0016.8036.120.261
Meloidogyne4.422.851.5576.0033.6711.3247.440.228
Gracilacus3.062.751.1117.3328.337.8555.290.538
Prismatolaimus2.671.861.4420.6741.676.8562.140.161
Acrobeloides2.522.161.1736.3337.676.4668.600.209
Filenchus1.660.802.07133.00123.334.2572.850.949
Alaimus1.541.271.2120.0016.003.9376.780.45
Ditylenchus1.300.891.4515.3313.333.3380.110.245
Acrobeles1.131.290.8812.332.002.8983.000.285
Aphelenchoides0.960.681.4218.0016.672.4685.460.936
Dorylaimida0.940.741.284.3310.672.4287.880.103
Boleodorus0.830.551.5110.336.002.1290.000.114
Pseudacrobeles0.800.551.468.671.002.0492.040.444
Plectus0.690.351.9510.6717.671.7793.810.979
Aporcelaimellus0.440.391.133.672.001.1294.930.171
Clarkus0.440.391.104.000.001.1196.040.026
Ceratoplectus0.400.172.365.001.001.0397.070.784
Diphtherophora0.360.331.081.333.670.9297.990.48
Helicotylenchus0.240.280.871.002.000.6298.610.921
Cervidellus0.210.161.321.003.000.5499.150.758
Tylocephalus0.170.180.921.331.000.4499.590.909
Teratocephalus0.160.151.082.332.000.41100.000.999
Diplogasteridae0.000.00NaN0.000.000.00100.001
Ecphyadophora0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
Nov-17
Control vs SLRAverage dissimilarity = 34.96
Alaimus4.213.081.3631.0076.3312.0312.030.292
Xenocriconemella4.163.501.1995.00112.0011.9123.940.922
Meloidogyne3.551.462.4247.3358.6710.1534.090.514
Helicotylenchus3.474.400.7956.676.009.9144.000.485
Rhabditidae2.462.071.1930.6746.677.0451.040.743
Prismatolaimus2.210.852.6143.6737.336.3257.360.587
Gracilacus2.161.311.6558.6764.006.1863.540.932
Filenchus1.881.761.07106.00130.335.3868.920.987
Aphelenchoides1.381.211.1417.0027.003.9472.860.41
Ditylenchus1.310.602.2021.334.333.7676.620.521
Acrobeles1.281.241.0321.006.003.6880.300.571
Pseudacrobeles1.161.011.1415.674.333.3183.610.371
Boleodorus0.930.621.514.0014.002.6786.280.258
Acrobeloides0.690.621.1214.6711.671.9888.260.86
Plectus0.670.451.4829.6722.001.9190.170.901
Tripyla0.530.501.065.005.331.5391.700.311
Dorylaimida0.530.391.3411.6713.671.5093.200.837
Diphtherophora0.450.281.626.675.001.2994.490.479
Ceratoplectus0.420.281.528.338.331.2095.690.778
Aporcelaimellus0.370.371.004.007.331.0596.740.652
Teratocephalus0.300.330.903.332.670.8697.600.218
Clarkus0.280.281.013.336.670.8098.400.903
Tylocephalus0.170.141.272.331.330.5098.900.737
Ecphyadophora0.160.121.362.331.000.4699.360.548
Cervidellus0.140.150.961.671.000.4199.770.744
Diplogasteridae0.080.120.661.000.000.23100.000.741
Aphelenchus0.000.00NaN0.000.000.00100.001
Control vs R2MAverage dissimilarity = 43.16
Xenocriconemella5.713.341.7195.0038.0013.2213.220.437
Helicotylenchus4.384.920.8956.671.0010.1423.360.008
Meloidogyne4.063.201.2747.3351.679.3932.750.289
Filenchus3.602.071.74106.00142.678.3541.100.705
Rhabditidae3.422.801.2230.6760.677.9349.030.476
Alaimus3.292.701.2231.0044.337.6256.650.66
Gracilacus3.161.062.9758.6721.677.3263.970.733
Prismatolaimus2.881.911.5143.6724.676.6770.640.133
Acrobeles1.801.381.3021.0012.004.1874.820.137
Plectus1.530.522.9629.6711.673.5478.360.023
Pseudacrobeles1.321.071.2315.6710.333.0581.410.193
Acrobeloides1.150.771.4914.6715.002.6684.070.381
Ditylenchus0.980.791.2421.3310.672.2786.340.691
Dorylaimida0.870.581.5011.672.672.0188.350.08
Aphelenchoides0.800.581.3917.0016.331.8690.210.784
Boleodorus0.730.362.034.0011.331.7091.910.72
Ceratoplectus0.700.411.698.331.001.6293.530.094
Clarkus0.600.620.963.337.671.3894.910.448
Tripyla0.480.481.015.002.001.1196.020.43
Diphtherophora0.390.390.996.674.000.9196.930.618
Aporcelaimellus0.340.301.124.005.670.7797.700.753
Teratocephalus0.250.380.663.330.000.5998.290.34
Tylocephalus0.190.171.172.330.000.4598.740.632
Diplogasteridae0.190.220.891.001.670.4599.190.27
Ecphyadophora0.190.151.292.331.000.4499.630.281
Cervidellus0.160.170.941.671.000.37100.000.674
Aphelenchus0.000.00NaN0.000.000.00100.001
Control vs R2WAverage dissimilarity = 44.59
Gracilacus7.544.601.6458.6772.0016.9016.900.188
Xenocriconemella4.614.001.1595.0080.6710.3527.250.837
Helicotylenchus4.375.120.8556.673.009.8037.050.006
Filenchus4.352.551.71106.0063.679.7546.800.432
Meloidogyne4.192.231.8847.3355.009.4056.200.222
Prismatolaimus3.261.911.7143.6713.677.3263.520.036
Alaimus2.592.541.0231.0015.335.8169.330.909
Acrobeles2.021.461.3921.001.004.5373.860.07
Rhabditidae1.921.661.1630.6720.674.3178.170.838
Plectus1.550.921.6929.6712.673.4781.640.023
Pseudacrobeles1.281.021.2515.679.332.8784.510.208
Ditylenchus1.161.101.0621.3326.332.6187.120.589
Ceratoplectus0.820.402.088.330.001.8488.960.024
Dorylaimida0.680.501.3511.675.671.5290.480.491
Acrobeloides0.590.411.4514.6718.001.3391.810.932
Aphelenchoides0.580.421.3717.0021.331.2993.100.939
Diphtherophora0.530.401.346.672.001.2094.300.19
Tripyla0.490.580.845.000.001.0995.390.37
Boleodorus0.460.570.804.001.001.0396.420.981
Clarkus0.320.231.373.333.670.7197.130.853
Cervidellus0.270.310.861.672.330.6097.730.409
Teratocephalus0.260.390.673.330.000.5998.320.253
Tylocephalus0.250.191.322.333.000.5698.880.323
Aporcelaimellus0.230.191.184.003.670.5199.390.851
Ecphyadophora0.180.131.392.331.670.3999.780.408
Diplogasteridae0.100.140.671.000.000.22100.000.508
Aphelenchus0.000.00NaN0.000.000.00100.001
SLR vs R2MAverage dissimilarity = 37.03
Xenocriconemella6.873.941.75112.0038.0018.5518.550.12
Alaimus3.853.531.0976.3344.3310.4128.960.458
Rhabditidae3.483.061.1446.6760.679.3938.350.429
Gracilacus3.472.551.3664.0021.679.3647.710.614
Meloidogyne3.122.091.4958.6751.678.4356.140.735
Filenchus2.350.962.43130.33142.676.3462.480.939
Prismatolaimus1.810.961.8937.3324.674.8767.350.894
Aphelenchoides1.741.271.3727.0016.334.7172.060.127
Acrobeloides1.261.131.1211.6715.003.3975.450.308
Acrobeles1.151.081.066.0012.003.1078.550.719
Dorylaimida0.920.521.7613.672.672.4881.030.06
Boleodorus0.900.362.4814.0011.332.4583.480.315
Plectus0.840.451.8922.0011.672.2885.760.695
Ditylenchus0.840.631.334.3310.672.2688.020.829
Pseudacrobeles0.670.661.014.3310.331.8189.830.81
Clarkus0.670.491.386.677.671.8091.630.336
Ceratoplectus0.600.461.308.331.001.6193.240.263
Helicotylenchus0.500.451.126.001.001.3694.600.91
Tripyla0.480.530.905.332.001.2895.880.44
Aporcelaimellus0.470.461.017.335.671.2697.140.376
Diphtherophora0.350.211.675.004.000.9598.090.728
Teratocephalus0.200.310.662.670.000.5598.640.612
Diplogasteridae0.170.250.660.001.670.4599.090.468
Ecphyadophora0.120.150.821.001.000.3399.420.881
Cervidellus0.110.140.831.001.000.3099.720.82
Tylocephalus0.100.150.661.330.000.28100.000.943
Aphelenchus0.000.00NaN0.000.000.00100.001
SLR vs R2WAverage dissimilarity = 44.30
Gracilacus7.454.771.5664.0072.0016.8116.810.207
Filenchus6.062.352.58130.3363.6713.6730.480.045
Alaimus5.753.181.8176.3315.3312.9743.450.035
Xenocriconemella5.703.691.54112.0080.6712.8656.310.406
Rhabditidae2.912.861.0246.6720.676.5762.880.602
Prismatolaimus2.150.962.2537.3313.674.8667.740.621
Ditylenchus2.031.491.364.3326.334.5772.310.05
Meloidogyne1.931.421.3658.6755.004.3676.670.99
Aphelenchoides1.641.161.4227.0021.333.7180.380.186
Boleodorus1.160.821.4214.001.002.6182.990.033
Acrobeloides0.900.851.0611.6718.002.0485.030.593
Plectus0.870.781.1222.0012.671.9787.000.656
Dorylaimida0.760.471.6113.675.671.7188.710.282
Ceratoplectus0.710.441.628.330.001.6090.310.071
Pseudacrobeles0.600.461.314.339.331.3691.670.87
Helicotylenchus0.540.421.296.003.001.2292.890.852
Aporcelaimellus0.500.391.287.333.671.1394.020.236
Acrobeles0.490.331.466.001.001.1095.120.932
Clarkus0.460.281.676.673.671.0496.160.59
Tripyla0.430.640.675.330.000.9697.120.591
Diphtherophora0.420.341.245.002.000.9598.070.56
Tylocephalus0.260.221.141.333.000.5898.650.306
Cervidellus0.250.280.881.002.330.5599.200.473
Teratocephalus0.210.320.672.670.000.4899.680.528
Ecphyadophora0.140.121.171.001.670.32100.000.753
Aphelenchus0.000.00NaN0.000.000.00100.001
Diplogasteridae0.000.00NaN0.000.000.00100.001
R2M vs R2WAverage dissimilarity = 47.64
Filenchus8.233.222.56142.6763.6717.2817.280.001
Gracilacus7.358.750.8421.6772.0015.4332.710.227
Xenocriconemella6.524.921.3338.0080.6713.6946.400.163
Rhabditidae4.214.071.0360.6720.678.8455.240.154
Meloidogyne4.072.641.5451.6755.008.5363.770.286
Alaimus3.442.521.3644.3315.337.2371.000.583
Prismatolaimus1.871.581.1824.6713.673.9174.910.816
Ditylenchus1.791.691.0610.6726.333.7778.680.183
Acrobeloides1.450.841.7215.0018.003.0481.720.111
Acrobeles1.211.660.7312.001.002.5584.270.655
Boleodorus1.100.343.2711.331.002.3086.570.068
Aphelenchoides0.940.791.1916.3321.331.9888.550.663
Pseudacrobeles0.900.641.4210.339.331.8990.440.61
Plectus0.800.591.3711.6712.671.6992.130.755
Clarkus0.800.721.117.673.671.6893.810.102
Aporcelaimellus0.490.321.545.673.671.0394.840.278
Dorylaimida0.420.291.442.675.670.8895.720.955
Diphtherophora0.380.201.864.002.000.8096.520.653
Helicotylenchus0.360.430.831.003.000.7597.270.99
Tylocephalus0.320.291.120.003.000.6897.950.06
Cervidellus0.290.340.851.002.330.6198.560.219
Diplogasteridae0.210.320.671.670.000.4599.010.133
Tripyla0.200.300.672.000.000.4299.430.845
Ecphyadophora0.170.151.151.001.670.3699.790.478
Ceratoplectus0.100.150.671.000.000.21100.001
Aphelenchus0.000.00NaN0.000.000.00100.001
Teratocephalus0.000.00NaN0.000.000.00100.001
Jan-18
Control vs SLRAverage dissimilarity = 43.28
Filenchus8.386.271.34191.33156.6719.3619.360.832
Xenocriconemella6.543.871.6957.67108.6715.1134.470.807
Gracilacus3.992.781.4349.0042.339.2043.670.448
Pseudacrobeles3.091.831.6937.332.007.1450.810.053
Plectus2.332.171.0740.6721.005.3756.180.532
Ditylenchus2.052.061.0028.009.004.7460.920.317
Prismatolaimus1.911.211.5824.6719.334.4065.320.533
Helicotylenchus1.881.461.2923.332.334.3569.670.087
Acrobeloides1.861.601.1623.3322.004.3073.970.71
Aphelenchoides1.591.221.3025.339.333.6777.640.316
Rhabditidae1.550.821.8922.0027.333.5881.220.673
Meloidogyne1.461.131.3029.6742.003.3884.600.89
Acrobeles1.371.710.802.6716.673.1787.770.49
Tylocephalus0.830.761.099.002.331.9189.680.249
Ceratoplectus0.620.750.837.001.331.4391.110.362
Boleodorus0.620.581.076.330.001.4392.540.089
Ecphyadophora0.590.361.646.670.001.3693.900.321
Cervidellus0.480.371.305.671.331.1295.020.257
Teratocephalus0.470.431.095.332.001.0796.090.4
Alaimus0.430.221.9310.008.001.0097.090.916
Aporcelaimellus0.340.301.174.002.330.7997.880.603
Clarkus0.260.390.663.330.000.6098.480.509
Diphtherophora0.240.280.862.331.000.5699.040.409
Dorylaimida0.220.330.652.330.000.5099.540.422
Diplogasteridae0.200.171.202.330.000.46100.000.203
Tripyla0.000.00NaN0.000.000.00100.001
Control vs R2MAverage dissimilarity = 49.59
Filenchus10.974.622.38191.3393.3322.1222.120.239
Xenocriconemella4.874.211.1657.6716.339.8231.940.929
Gracilacus4.614.770.9749.0011.009.2941.230.299
Plectus3.342.961.1340.6710.336.7447.970.046
Pseudacrobeles3.332.151.5537.338.336.7254.690.031
Helicotylenchus2.401.851.3023.330.674.8459.530.018
Meloidogyne2.391.341.7829.6710.334.8264.350.429
Prismatolaimus2.372.021.1724.676.004.7869.130.144
Acrobeloides2.131.971.0823.3318.674.2973.420.544
Ditylenchus2.122.230.9528.0019.674.2877.700.314
Aphelenchoides2.061.671.2425.339.674.1681.860.097
Alaimus1.190.542.1910.000.672.4184.270.056
Tylocephalus1.181.151.039.000.002.3886.650.013
Rhabditidae0.980.821.2022.0015.331.9988.640.956
Boleodorus0.810.721.116.330.001.6290.260.01
Ceratoplectus0.811.010.807.000.001.6391.890.034
Acrobeles0.760.671.132.675.671.5493.430.736
Cervidellus0.590.381.575.672.001.1994.620.068
Ecphyadophora0.580.451.306.673.331.1795.790.373
Teratocephalus0.510.580.895.330.671.0396.820.22
Clarkus0.390.351.133.331.330.8097.620.086
Aporcelaimellus0.390.251.574.002.000.7898.400.445
Diphtherophora0.280.420.662.330.000.5698.960.282
Dorylaimida0.280.420.662.330.000.5699.520.025
Diplogasteridae0.240.191.282.330.670.48100.000.062
Tripyla0.000.00NaN0.000.000.00100.001
Control vs R2WAverage dissimilarity = 49.09
Filenchus10.405.811.79191.3388.3321.1821.180.359
Xenocriconemella8.599.060.9557.6793.6717.5038.680.605
Gracilacus4.084.450.9249.0014.678.3146.990.437
Plectus3.332.861.1740.675.676.7853.770.062
Pseudacrobeles2.941.881.5637.3312.335.9959.760.074
Prismatolaimus2.392.221.0824.671.004.8764.630.154
Helicotylenchus2.221.671.3323.331.004.5369.160.03
Acrobeloides2.221.541.4523.3318.334.5373.690.441
Ditylenchus2.132.091.0228.0013.674.3478.030.263
Meloidogyne1.571.041.5029.6716.333.1981.220.825
Aphelenchoides1.290.891.4425.3316.332.6383.850.497
Tylocephalus1.050.971.089.000.672.1485.990.034
Rhabditidae1.030.771.3422.0023.332.0988.080.945
Alaimus0.800.411.9510.003.001.6389.710.409
Ceratoplectus0.740.930.807.000.001.5191.220.082
Boleodorus0.740.671.106.330.001.5192.730.026
Ecphyadophora0.700.411.706.670.001.4294.150.142
Cervidellus0.570.381.535.671.001.1795.320.077
Teratocephalus0.480.540.885.330.670.9896.300.325
Aporcelaimellus0.440.331.314.000.000.8997.190.234
Acrobeles0.320.301.052.670.000.6597.840.788
Clarkus0.300.450.663.330.000.6098.440.356
Diphtherophora0.280.340.812.330.670.5699.000.268
Dorylaimida0.250.380.662.330.000.5299.520.126
Diplogasteridae0.230.191.222.330.000.48100.000.063
Tripyla0.000.00NaN0.000.000.00100.001
SLR vs R2MAverage dissimilarity = 52.55
Xenocriconemella12.825.492.34108.6716.3324.3924.390.183
Filenchus12.774.882.62156.6793.3324.3048.690.068
Meloidogyne4.902.731.7942.0010.339.3358.020.002
Gracilacus4.702.431.9342.3311.008.9366.950.254
Rhabditidae2.481.501.6627.3315.334.7271.670.138
Acrobeles2.212.290.9616.675.674.2075.870.081
Acrobeloides2.082.380.8722.0018.673.9579.820.607
Plectus1.691.161.4721.0010.333.2383.050.602
Prismatolaimus1.660.921.8119.336.003.1686.210.567
Ditylenchus1.631.241.319.0019.673.0989.300.53
Alaimus1.241.121.118.000.672.3691.660.034
Pseudacrobeles0.960.741.292.008.331.8293.480.94
Aphelenchoides0.790.611.289.339.671.5094.980.909
Ecphyadophora0.520.630.810.003.330.9895.960.488
Aporcelaimellus0.410.321.292.332.000.7896.740.361
Helicotylenchus0.300.350.872.330.670.5897.320.883
Teratocephalus0.300.320.942.000.670.5797.890.657
Tylocephalus0.280.211.312.330.000.5398.420.766
Cervidellus0.280.241.141.332.000.5398.950.885
Clarkus0.190.161.190.001.330.3699.310.563
Ceratoplectus0.150.230.661.330.000.2999.600.64
Diphtherophora0.130.190.661.000.000.2499.840.631
Diplogasteridae0.080.130.640.000.670.16100.000.856
Boleodorus0.000.00NaN0.000.000.00100.001
Dorylaimida0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
SLR vs R2WAverage dissimilarity = 47.81
Xenocriconemella12.655.452.32108.6793.6726.4626.460.22
Filenchus11.726.941.69156.6788.3324.5150.970.181
Gracilacus4.312.281.9042.3314.679.0259.990.352
Meloidogyne3.532.101.6942.0016.337.4067.390.053
Rhabditidae2.281.691.3527.3323.334.7672.150.196
Prismatolaimus2.180.732.9819.331.004.5776.720.33
Acrobeloides2.101.771.1822.0018.334.3881.100.54
Plectus1.840.931.9821.005.673.8584.950.54
Acrobeles1.792.450.7316.670.003.7688.710.309
Pseudacrobeles1.291.131.142.0012.332.7091.410.853
Aphelenchoides1.091.001.099.3316.332.2793.680.681
Alaimus0.780.830.948.003.001.6395.310.448
Ditylenchus0.680.571.209.0013.671.4196.720.951
Helicotylenchus0.310.320.992.331.000.6697.380.849
Teratocephalus0.270.290.912.000.670.5697.940.711
Tylocephalus0.240.171.442.330.670.5198.450.814
Aporcelaimellus0.240.370.662.330.000.5298.970.893
Cervidellus0.210.230.901.331.000.4399.400.952
Diphtherophora0.150.160.901.000.670.3199.710.566
Ceratoplectus0.140.210.661.330.000.29100.000.696
Boleodorus0.000.00NaN0.000.000.00100.001
Clarkus0.000.00NaN0.000.000.00100.001
Diplogasteridae0.000.00NaN0.000.000.00100.001
Dorylaimida0.000.00NaN0.000.000.00100.001
Ecphyadophora0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
R2M vs R2WAverage dissimilarity = 39.42
Xenocriconemella13.4615.760.8516.3393.6734.1434.140.148
Filenchus7.114.321.6593.3388.3318.0352.170.946
Rhabditidae2.411.951.2415.3323.336.1258.290.155
Acrobeloides2.331.301.8018.6718.335.9264.210.392
Gracilacus2.021.051.9311.0014.675.1269.330.931
Ditylenchus1.790.652.7719.6713.674.5473.870.484
Aphelenchoides1.641.531.079.6716.334.1778.040.281
Meloidogyne1.430.971.4810.3316.333.6481.680.92
Pseudacrobeles1.371.221.138.3312.333.4785.150.83
Plectus0.980.891.1010.335.672.4987.640.961
Prismatolaimus0.960.501.906.001.002.4390.070.934
Acrobeles0.911.370.665.670.002.3092.370.647
Ecphyadophora0.680.810.843.330.001.7394.100.182
Alaimus0.580.461.250.673.001.4795.570.782
Aporcelaimellus0.390.391.022.000.001.0096.570.411
Cervidellus0.340.271.262.001.000.8697.430.771
Clarkus0.250.201.251.330.000.6498.070.472
Helicotylenchus0.240.290.830.671.000.6298.690.908
Teratocephalus0.180.210.820.670.670.4499.130.832
Tylocephalus0.130.200.660.000.670.3499.470.935
Diplogasteridae0.110.160.660.670.000.2799.740.686
Diphtherophora0.100.150.660.000.670.26100.000.768
Boleodorus0.000.00NaN0.000.000.00100.001
Ceratoplectus0.000.00NaN0.000.000.00100.001
Dorylaimida0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
May-18
Control vs SLRAverage dissimilarity = 40.20
Meloidogyne7.315.991.22135.33140.6718.1718.170.85
Filenchus4.873.141.55130.6776.6712.1230.290.822
Xenocriconemella3.723.581.0418.0046.679.2439.530.749
Acrobeles2.661.741.5332.679.676.6046.130.116
Gracilacus2.100.942.2428.334.335.2251.350.057
Helicotylenchus2.032.480.8222.333.675.0556.400.414
Rhabditidae2.021.561.3046.0034.005.0261.420.525
Plectus2.011.401.4445.6724.674.9966.410.669
Prismatolaimus1.781.531.1721.6730.674.4370.840.538
Ditylenchus1.761.301.3524.334.334.3775.210.054
Alaimus1.691.071.5924.3338.004.2079.410.871
Ceratoplectus1.080.631.7215.003.332.6882.090.127
Acrobeloides0.980.701.4022.3318.002.4484.530.96
Pseudacrobeles0.960.432.2314.674.002.3886.910.09
Aphelenchoides0.920.631.4715.005.672.2989.200.822
Boleodorus0.900.521.7312.673.002.2291.420.091
Aporcelaimellus0.510.351.446.001.671.2692.680.141
Tripyla0.500.441.155.002.331.2693.940.261
Dorylaimida0.470.351.348.677.001.1595.090.79
Clarkus0.460.311.455.671.671.1496.230.12
Cervidellus0.440.311.425.000.671.0997.320.37
Diphtherophora0.370.291.282.674.330.9398.250.595
Tylocephalus0.270.221.233.330.670.6898.930.262
Diplogasteridae0.200.290.662.330.000.4999.420.473
Ecphyadophora0.120.180.661.330.000.2999.710.83
Teratocephalus0.120.180.661.330.000.29100.000.735
Control vs R2MAverage dissimilarity = 42.25
Meloidogyne7.815.321.47135.33190.6718.4718.470.762
Filenchus7.762.493.12130.6749.3318.3736.840.083
Acrobeles2.932.171.3532.675.676.9443.780.052
Gracilacus2.171.191.8228.334.675.1348.910.041
Helicotylenchus2.072.890.7222.330.004.9153.820.374
Alaimus1.841.471.2524.336.674.3658.180.828
Plectus1.691.401.2145.6728.004.0062.180.845
Acrobeloides1.630.812.0122.3332.673.8666.040.609
Xenocriconemella1.491.500.9918.0010.003.5269.560.887
Ceratoplectus1.380.701.9615.001.003.2772.830.012
Rhabditidae1.371.480.9246.0033.333.2576.080.855
Ditylenchus1.351.291.0524.339.673.1979.270.433
Prismatolaimus1.311.191.1121.6710.003.1182.380.771
Boleodorus1.180.343.4812.670.002.7985.170.011
Aphelenchoides1.160.941.2415.0023.332.7587.920.749
Pseudacrobeles1.130.313.6814.672.672.6790.590.011
Dorylaimida0.790.441.808.670.001.8792.460.093
Aporcelaimellus0.590.511.166.000.001.4193.870.042
Clarkus0.530.431.245.670.001.2695.130.036
Cervidellus0.480.381.285.003.331.1496.270.227
Tripyla0.440.660.665.000.001.0497.310.429
Diphtherophora0.300.370.802.670.670.7098.010.841
Tylocephalus0.280.251.113.331.000.6798.680.195
Ecphyadophora0.210.240.881.331.670.4999.170.534
Diplogasteridae0.200.310.662.330.000.4899.650.329
Teratocephalus0.150.150.941.330.670.35100.000.621
Control vs R2WAverage dissimilarity = 56.30
Filenchus11.481.836.26130.6725.0020.3820.380.001
Meloidogyne7.474.991.50135.33114.3313.2733.650.837
Xenocriconemella4.273.641.1718.0047.337.5941.240.663
Plectus4.231.512.8045.676.677.5148.750.002
Acrobeles3.572.731.3132.670.006.3555.100.013
Alaimus2.771.631.7024.330.004.9160.010.239
Rhabditidae2.621.771.4846.0021.004.6564.660.1
Gracilacus2.591.222.1228.333.674.6069.260.003
Helicotylenchus2.363.040.7822.333.674.1973.450.124
Prismatolaimus2.061.441.4321.671.673.6777.120.482
Ceratoplectus1.700.792.1415.000.003.0180.130.001
Ditylenchus1.641.491.1024.338.672.9283.050.12
Boleodorus1.350.363.7212.670.002.4085.450.001
Pseudacrobeles1.280.403.1914.673.002.2787.720.003
Acrobeloides1.080.771.4022.3314.001.9289.640.927
Aphelenchoides1.020.811.2615.0016.671.8191.450.813
Dorylaimida0.900.491.848.670.001.6093.050.032
Aporcelaimellus0.690.601.156.000.001.2394.280.009
Clarkus0.610.491.265.670.001.0895.360.009
Cervidellus0.560.441.275.000.001.0196.370.116
Tripyla0.500.750.665.000.000.8897.250.27
Diphtherophora0.400.321.242.672.330.7097.950.551
Tylocephalus0.360.301.173.330.000.6498.590.021
Teratocephalus0.350.390.891.332.670.6299.210.436
Diplogasteridae0.270.300.902.331.000.4899.690.131
Ecphyadophora0.180.200.901.331.000.31100.000.573
SLR vs R2MAverage dissimilarity = 38.70
Meloidogyne9.876.151.60140.67190.6725.5225.520.292
Xenocriconemella4.485.670.7946.6710.0011.5837.100.566
Filenchus4.144.300.9676.6749.3310.6947.790.924
Alaimus3.621.961.8538.006.679.3557.140.055
Prismatolaimus2.292.251.0230.6710.005.9363.070.384
Acrobeloides2.251.491.5118.0032.675.8268.890.16
Rhabditidae1.881.171.6234.0033.334.8773.760.59
Aphelenchoides1.881.381.365.6723.334.8678.620.143
Plectus1.320.701.8924.6728.003.4282.040.96
Acrobeles1.060.861.249.675.672.7584.790.825
Ditylenchus0.860.551.584.339.672.2387.020.631
Dorylaimida0.780.421.877.000.002.0389.050.119
Gracilacus0.720.361.984.334.671.8590.900.969
Diphtherophora0.500.351.424.330.671.2992.190.158
Helicotylenchus0.450.680.663.670.001.1693.350.819
Pseudacrobeles0.430.361.184.002.671.1194.460.97
Ceratoplectus0.370.361.033.331.000.9595.410.908
Cervidellus0.370.430.840.673.330.9596.360.551
Boleodorus0.300.460.663.000.000.7897.140.918
Tripyla0.290.231.272.330.000.7497.880.538
Ecphyadophora0.220.330.660.001.670.5698.440.527
Aporcelaimellus0.210.171.231.670.000.5398.970.744
Clarkus0.180.141.291.670.000.4899.450.79
Tylocephalus0.130.140.960.671.000.3599.800.755
Teratocephalus0.080.120.660.000.670.20100.000.869
Diplogasteridae0.000.00NaN0.000.000.00100.001
SLR vs R2WAverage dissimilarity = 48.26
Meloidogyne9.876.171.60140.67114.3320.4420.440.322
Filenchus7.285.611.3076.6725.0015.0935.530.142
Xenocriconemella6.116.250.9846.6747.3312.6748.200.124
Alaimus5.121.942.6438.000.0010.6258.820.002
Prismatolaimus3.692.431.5230.671.677.6566.470.005
Rhabditidae2.541.421.7934.0021.005.2771.740.141
Plectus2.511.931.3024.676.675.1976.930.339
Aphelenchoides1.631.401.175.6716.673.3880.310.356
Acrobeloides1.471.101.3318.0014.003.0583.360.726
Acrobeles1.231.031.199.670.002.5485.900.793
Ditylenchus0.980.492.024.338.672.0387.930.55
Dorylaimida0.930.491.917.000.001.9289.850.03
Gracilacus0.720.282.594.333.671.4991.340.973
Helicotylenchus0.690.591.163.673.671.4292.760.575
Pseudacrobeles0.520.421.244.003.001.0893.840.894
Diphtherophora0.490.321.544.332.331.0294.860.186
Ceratoplectus0.490.451.093.330.001.0295.880.79
Teratocephalus0.390.590.660.002.670.8096.680.399
Boleodorus0.350.530.663.000.000.7497.420.855
Tripyla0.350.271.282.330.000.7198.130.501
Aporcelaimellus0.250.201.241.670.000.5198.640.665
Clarkus0.220.171.301.670.000.4599.090.75
Diplogasteridae0.120.180.660.001.000.2599.340.714
Ecphyadophora0.120.180.660.001.000.2599.590.776
Cervidellus0.100.150.660.670.000.2199.800.915
Tylocephalus0.100.150.660.670.000.20100.000.906
R2M vs R2WAverage dissimilarity = 37.48
Meloidogyne11.647.201.62190.67114.3331.0631.060.099
Xenocriconemella5.225.870.8910.0047.3313.9344.990.323
Filenchus3.882.251.7249.3325.0010.3555.340.941
Plectus3.080.833.6928.006.678.2263.560.093
Acrobeloides2.991.581.8932.6714.007.9671.520.014
Aphelenchoides1.901.401.3623.3316.675.0876.600.135
Rhabditidae1.730.852.0433.3321.004.6181.210.703
Prismatolaimus1.270.881.4410.001.673.3984.600.815
Gracilacus0.900.990.914.673.672.4087.000.873
Alaimus0.880.751.186.670.002.3589.350.997
Acrobeles0.691.040.665.670.001.8591.200.943
Helicotylenchus0.550.580.960.003.671.4892.680.663
Ditylenchus0.510.451.149.678.671.3594.030.971
Teratocephalus0.450.560.810.672.671.2195.240.189
Cervidellus0.410.610.663.330.001.0996.330.453
Pseudacrobeles0.350.331.072.673.000.9497.270.987
Diphtherophora0.330.321.030.672.330.8898.150.761
Ecphyadophora0.320.380.841.671.000.8599.000.118
Diplogasteridae0.130.200.660.001.000.3599.350.6
Ceratoplectus0.120.180.661.000.000.3299.670.997
Tylocephalus0.120.180.661.000.000.33100.000.781
Aporcelaimellus0.000.00NaN0.000.000.00100.001
Boleodorus0.000.00NaN0.000.000.00100.001
Clarkus0.000.00NaN0.000.000.00100.001
Dorylaimida0.000.00NaN0.000.000.00100.001
Tripyla0.000.00NaN0.000.000.00100.001
DOI: https://doi.org/10.2478/jofnem-2022-0022 | Journal eISSN: 2640-396X | Journal ISSN: 0022-300X
Language: English
Submitted on: Feb 15, 2022
Published on: Jul 20, 2022
Published by: Society of Nematologists, Inc.
In partnership with: Paradigm Publishing Services
Publication frequency: 1 issue per year

© 2022 Satyendra Kumar Pothula, Gary Phillips, Ernest C. Bernard, published by Society of Nematologists, Inc.
This work is licensed under the Creative Commons Attribution 4.0 License.