Table 1
Inoculated carrier materials containing various volumes of bacterial liquid culture and amounts of carrier materials
Tabelle 1. Inokulierte Trägermaterialien, die verschiedene Volumina an bakterieller Flüssigkultur und Mengen an Trägermaterialien
| Carrier materials | Carrier material (g) | Liquid culture (ml) | Inoculated carrier materials (g) |
|---|---|---|---|
| LC | 100 | 205 | 305 |
| WC | 125 | 176 | 301 |
| LN | 174 | 127 | 301 |
| VC | 174 | 126 | 300 |
| FYM | 173 | 130 | 303 |
Table 2
Chemical properties of the selected carrier materials
Tabelle 2. Chemische Eigenschaften ausgewählter Trägermaterialien
| Carrier material | N(%) | OC(%) | pH | EC(S/m) | Moisture (%) | References |
|---|---|---|---|---|---|---|
| LC | 0.78 | 58.60 | 7.36 | 597 | 5.90 | Abebe et al., 2017 |
| WC | 0.72 | 49.50 | 7.01 | 512 | 7.20 | Sudhakar et al., 2004 |
| Lignite | 0.86 | 29.30 | 6.58 | 642 | 9.80 | Rumpel et al., 1998 |
| VC | 1.01 | 25.90 | 7.10 | 370 | 17.58 | Packialakshmi and Aliya, 2014; Ravimycin, 2016 |
| FYM | 1.83 | 51.80 | 6.80 | 330 | 15.74 | Ravimycin, 2016 |
Table 3
Water absorption (holding), retention (% held), and loss (% in 6 months) of different carrier materials
Tabelle 3. Wasseraufnahme (Halten), Retention (% gehalten) und Verlust (% in 6 Monaten) verschiedener Trägermaterialien
| Carrier material | Water absorbed (ml) | Water held (%) | Moisture lost (%) | |
|---|---|---|---|---|
| At the start | After 6 months | |||
| LC | 20.56 ± 0.13e | 205.6 ± 1.38e | 93.13 ± 2.73e | 54.71 ± 1.02e |
| WC | 14.08 ± 0.20d | 140.86 ± 2.33d | 64.86 ± 2.31d | 53.87 ± 2.38d |
| Lignite | 7.35 ± 0.11b | 73.56 ± 1.15b | 44.83 ± 2.84b | 38.90 ± 4.83b |
| VC | 7.26 ± 0.13a | 72.6 ± 1.24a | 41.10 ± 1.61a | 43.48 ± 2.65c |
| FYM | 7.53 ± 0.19c | 75.3 ± 1.90c | 51.33 ± 2.52c | 31.86 ± 2.26a |
| LSD (0.05) | 0.39 | 3.91 | 6.26 | 7.49 |
[i] Values are the means ± SE. Values within the same column followed by different superscript letters are significantly different at the p ≤ 0.05 level.
Table 4
PGPR (Azotobacter chroococcum 5576) survivability shown as CFU in various carriers as a function of time (days) at room temperature
Tabelle 4. Überlebensfähigkeit von PGPR (A. chroococcum 5576) gezeigt als CFU in verschiedenen Trägermaterialien als Funktion der Zeit (Tage) bei Raumtemperatur
| Carrier materials | PGPR CFU (× 107 per g) as obtained after various periods of storage (d) | ||||||
|---|---|---|---|---|---|---|---|
| 0 | 30 | 60 | 90 | 120 | 150 | 180 | |
| LC | 77 ± 8.19e | 147.3 ± 2.30e | 104.3 ± 6.00e | 98.33 ± 9.49e | 77.66 ± 7.83e | 27.00 ± 2.08e | 8.33 ± 1.20e |
| WC | 70.5 ± 3.48d | 90.66 ± 6.64d | 64.33 ± 5.60d | 32.00 ± 4.04d | 18.00 ± 1.73d | 10.66 ± 1.20d | 3.33 ± 0.33d |
| LN | 53.5 ± 2.33c | 82.33 ± 2.96c | 35.66 ± 2.02c | 31.66 ± 2.18c | 22.66 ± 2.02c | 9.33 ± 0.88c | 2.66 ± 0.33c |
| VC | 33.5 ± 2.60a | 46.66 ± 2.90a | 23.33 ± 1.76a | 16.33 ± 1.45a | 10.66 ± 0.88a | 1.66 ± 0.66a | 0.34 ± 0.04a |
| FYM | 47.5 ± 2.02b | 56.66 ± 3.48b | 21.33 ± 1.20b | 17.66 ± 0.88b | 08.33 ± 0.88b | 1.00 ± 0.57b | 0.14 ± 0.02b |
[i] Values are the means ± SE. Values within the same column followed by different superscript letters are significantly different at the p ≤ 0.05 level.
Table 5
Culture holding coefficients of the selected carrier materials
Tabelle 5. Kulturhaltekoeffizient ausgewählter Trägermaterialien
| Carrier materials | LC | WC | Lignite | VC | FYM |
| CHO | 4.69 | 4.36 | 6.70 | 5.50 | 6.50 |
[i] CHO, culture holding coefficient
Table 6
Standards for the preparation of carrier for Azotobacter biofertilizer
Tabelle 6. Standards für die Herstellung von Trägern für Azotobacter-Biodünger
| Parameters | Standard | References |
|---|---|---|
| Base material | Solid (moist/dry or granules form) or liquid based | BIS, 1985, Bhattacharjee, 2014;Yadav and Chandra, 2014 |
| Viable cell count | 5 × 107/g of carrier (CFU). Biofertilizer or 1 × 108 / ml of liquid base | Singh, 2015; BIS, 1985; Yadav and Chandra, 2014 |
| pH value | 6.5–7.5 | BIS, 1985; Yadav and Chandra, 2014 |
| Moisture % | By weight, 30%–40% for the carrier material | BIS, 1985; Yadav and Chandra, 2014 |
| Water retention | High water-holding capacity | BIS, 1985; Yadav and Chandra, 2014 |
| Partial size | Passable through 100 meshsieves | BIS, 1985; Yadav and Chandra, 2014 |
| Contamination level | None at 10−5 dilution | BIS, 1985; Yadav and Chandra, 2014 |
| Strain selection | Strain capable of fixing N2 at least 10 mg/g of sucrose consumed | BIS, 1985; Yadav and Chandra, 2014 |
Table 7
Performance of Azotobacter chroococcum 5576 regarding plant growth-promoting traits before (i) and after (f) storage period in the carrier LC
Tabelle 7. Leistung von A. chroococcum 5576 hinsichtlich der pflanzenwachstumsfördernden Merkmale vor (i) und nach (f) Lagerzeit in der Träger-L-Holzkohle
| Plant growth-promoting parameters | Performance (i) | Performance (f) |
|---|---|---|
| NFE (mg per g sucrose consumed) | 12.46 ± 0.35 | 12.45 ± 0.40 |
| PSI | 03.90 ± 0.10 | 03.34 ± 0.09 |
| PSU | 42.75 ± 0.78 | 42.80 ± 0.57 |
[i] Values are the mean of three replications ± SE. NFE, N2 fixation efficiency; PSI, phosphate-solubilizing index; PSU, percent siderophore production