Evaluating Vacuum and Steam Heat to Eliminate Pinewood Nematodes in Naturally Infested Whole Pine Logs

Eisenback, J. D.; Chen, Z.; White, M.

Evaluating Vacuum and Steam Heat to Eliminate Pinewood Nematodes in Naturally Infested Whole Pine Logs

Journal of Nematology

Volume 56 (2024): Issue 1 (March 2024)

By:

J. D. Eisenback, Z. Chen and M. White

Open Access

|Oct 2024

Figures & Tables

Sampling and extraction of the pinewood nematode (Bursaphelenchus xylophilus (Steiner & Buhrer, 1934) Nickle, 1971) from whole pine (Pinus spp.) logs. A) Thirty yellow pine (Pinus spp.) logs laid out in the woodlot and numbered, ready to be sampled for pinewood nematodes. B) Hole drilled in an area without bark with a 2.5 cm diameter Forstner drill-bit 2.5 cm in depth with chips collected and placed in a quart-size plastic bag (C) and kept on ice while in the field. C,D) Ten grams of wood chips were placed on a single sheet of facial tissue paper on a Baerman funnel filled with water and covered with the tissue. E,F) After 12–16 hours, 5ml of water was drained from the plastic tube and examined for nematodes with a dissecting microscope. G) Pinewood nematodes were tentatively identified by overall body shape and characteristic movement.

A) Whole yellow pine (Pinus spp.) logs were debarked at the woodlot and shipped to the research lab at Virginia Tech, where they were cut into 2.3 m lengths, and groups of four were placed on wooden pallets and randomly selected for the various treatments. B–D) The vacuum treatment set-up used in this research was custom-built inside a mobile trailer with a vacuum container, and the steam generator was used as the test chamber with the capacity to treat 4 whole 2.3 m logs at the same time. Temperature sensors were attached to the log at the same time at various sites on the log and inside the chamber.

Diagram of the sampling pattern for whole logs includes two sections to serve as controls to determine the presence of pinewood nematodes (Bursaphelenchus xylophilus (Steiner & Buhrer, 1934) Nickle, 1971) before treatment and 10 additional sites for sampling after treatment, including 5 near the surface and 5 at the center of the log. Each sample was obtained by drilling a 2.5 cm hole with a 2.5 cm diameter Forstner drill bit. The wood chips from each hole were placed in a plastic bag and stored in a cooler over ice until they were further processed.

A) Line graph of temperatures at various levels in and on logs and within the chamber during the treatment of 60°C for 60 min. B) Line graph of temperatures at various levels in and on logs and within the chamber during the treatment of 48°C for 15.

Numbers of failures for each treatment on the surface and in the center of naturally infested whole pine (Pinus spp_) logs for the eradication of pinewood nematodes, (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971)_

Treatment	Sample location	Number	Failures	Percent failure
48°C/15min	Surface	60	22	36.7
48°C/15min	Center	60	24	40.0
48°C/15min	Total	120	46	38.3
56°C/30min	Surface	60	8	13.3
56°C/30min	Center	60	33	55.0
56°C/30min	Total	120	41	34.2
60°C/60min	Surface	60	9	15.0
60°C/60min	Center	60	4	6.7
60°C/60min	Total	120	13	10.8
Total	Surface	180	39	21.7
Total	Center	180	61	33.9
Total	Total	360	100	27.8
Control	Surface	20	0	0.0
Control	Center	20	1^*	5.0
Total	Total	40	1^*	2.5

Testing dates, times, temperatures, and energy usage for the treatment of naturally infested whole pine (Pinus spp_) logs with pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971)_

Test	Date	Outside temp.	Vacuum time	Steam time	Holding time	Total time	Energy usage

	2021	°C	min	min	°C/min	min	kwh

Pine
1	Aug. 26	21	10	391	48/15	416	49.7
2	Aug. 30	22	9	464	48/15	488	58.4
3	Aug. 31	25	10	522	56/30	562	62.0
4	Sept. 1	22	11	311	60/60	382	41.5
5	Sept. 2	18	11	634	56/30	675	84.7
6	Sept. 3	16	10	598	60/60	668	74.2
7	Sept. 7	15	9	532	60/60	601	70.0
8	Sept. 8	21	9	511	56/30	550	62.7
9	Sept. 9	10	10	458	48/15	483	70.6

Means and standard deviations of pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) counts per gram of wood shavings from two depths and three treatments of naturally infested whole pine (Pinus spp_) logs_

Treatment schedule	Center		Surface		Total

	Average nematodes/g	Std. dev.	Average nematodes/g	Std. dev.	Average nematodes/g	Std. dev.
48°C/15min	2.5	11.3	0.4	0.5	2.9	0.9
56°C/30min	3.9	21.0	0.2	0.8	4.1	19.3
60°C/60min	0^*	0	0^*	0	0^*	0
Control	77	120.4	139.7	131.1	108	142.2

The experimental design with schedules of treatments for the eradication of pinewood nematodes, (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971), in naturally infested whole pine (Pinus spp_) logs_

Species	Treating schedule	Temperature target location	Number of logs/tests	Number of tests	Total number of logs
Pine	48°C/15min.	Center	4	3	12
Pine	56°C/30min.	Center	4	3	12
Pine	60°C/60min.	Center	4	3	12
Control			4		4

Means of pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) counts per gram of wood shavings from treated naturally infested whole pine (Pinus spp_) logs one year after treatment_

Sample number	Log number	Treatment	Nematodes/gram After treatment	Nematodes/gram 1 yr. later
1	16 Surface	48°C/15 min	1	7.9
2	16 Center	48°C/15 min	0	10.4
3	21 Surface	56°C/30 min	0	4.3
4	21 Center	56°C/30 min	1.6	4.3
5	3 Surface	60°C/60 min	0^*	7.3
6	3 Center	60°C/60 min	0^*	27

Percent increase pinewood nematode (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) populations in naturally infested whole pine (Pinus spp_) logs from the 60°C/60 min treatment 1 month after treatment from the surface and center sampling locations_

Sample	Initial	1 month later	Percent increase
Surface	0.14	17.1	12,214%
Center	0.27	5.5	2,037%
Total	0.21	11.3	5,381%

DOI: https://doi.org/10.2478/jofnem-2024-0038 | Journal eISSN: 2640-396X | Journal ISSN: 0022-300X

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Language: English

Submitted on: May 21, 2024

Published on: Oct 5, 2024

Published by: Society of Nematologists, Inc.

In partnership with: Paradigm Publishing Services

Publication frequency: 1 issue per year

Keywords:

environmentally friendly,

ISPM-15,

phytosanitary treatments,

spp.,

vacuum,

Related subjects:

© 2024 J. D. Eisenback, Z. Chen, M. White, published by Society of Nematologists, Inc.
This work is licensed under the Creative Commons Attribution 4.0 License.

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Evaluating Vacuum and Steam Heat to Eliminate Pinewood Nematodes in Naturally Infested Whole Pine Logs

Figures & Tables

Figure 1:

Figure 2:

Figure 3:

Figure 4:

Numbers of failures for each treatment on the surface and in the center of naturally infested whole pine (Pinus spp_) logs for the eradication of pinewood nematodes, (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971)_

Testing dates, times, temperatures, and energy usage for the treatment of naturally infested whole pine (Pinus spp_) logs with pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971)_

Means and standard deviations of pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) counts per gram of wood shavings from two depths and three treatments of naturally infested whole pine (Pinus spp_) logs_

The experimental design with schedules of treatments for the eradication of pinewood nematodes, (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971), in naturally infested whole pine (Pinus spp_) logs_

Means of pinewood nematodes (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) counts per gram of wood shavings from treated naturally infested whole pine (Pinus spp_) logs one year after treatment_

Percent increase pinewood nematode (Bursaphelenchus xylophilus (Steiner and Buhrer, 1934) Nickle, 1971) populations in naturally infested whole pine (Pinus spp_) logs from the 60°C/60 min treatment 1 month after treatment from the surface and center sampling locations_

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