Table 2.
Features of plant growth-promoting bacteria in isolates and SynCom.
| Strain and SynCom | BNF (nmol of ethylene h−1) | Phosphate solubilization | IAA (μg/mL) | Metallophores | ACC deaminase | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Fe | Mg | V | Mo | Zn | Ca | Cu | |||||||||||||
| Semiquantitative (mm) | Quantitative (μg/mL) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | Semiquantitative (mm) | Quantitative (%) | ||||
| Burkholderia sp. Z1AL11 | 16.6 ± 3.1 | 2.0 ± 0.3 | 10.8 ± 0.3 | 8.95 ± 0.2 | 4 ± 0.8 | - | - | - | 4 ± 0.4 | 5.8 ± 0.6 | 3 ± 0.7 | - | 4 ± 0.6 | 5.3 ± 0.6 | 3 ± 0.4 | - | 3 ± 0.4 | 11.2 ± 0.9 | - |
| Achromobacter xylosoxidans Z2K8 | - | 1 ± 0.2 | - | 13.8 ± 0.6 | 2 ± 0.3 | 15.8 ± 0.7 | 2 ± 0.2 | 10 ± 0.4 | 2 ± 0.6 | 18.9 ± 0.5* | 3 ± 0.6 | 10.1 ± 0.4* | 4 ± 0.8 | 34 ± 0.9* | 2 ± 0.4 | 18.8 ± 1.6* | 2 ± 0.6 | 19.1 ± 1.2* | - |
| Pseudomonas protegens E2HL9 | - | 1.8 ± 0.1 | 10.7 ± 0.3 | 3.12 ± 0.3 | 3 ± 0.4 | - | 1 ± 0.5 | - | 3 ± 0.4 | - | 2 ± 0.4 | - | 4 ± 0.6 | - | 2 ± 0.5 | - | 2 ± 0.3 | - | - |
| Klebsiella variicola R3J3HD7 | 28.5 ± 8.6 | 2.5 ± 0.3 | 11 ± 0.2 | 7.46 ± 0.4 | 1 ± 0.7 | - | - | 17.8 ± 0.6* | 1 ± 0.8 | 7.9 ± 0.9 | 1 ± 0.2 | - | 2 ± 0.4 | - | 2 ± 0.3 | 2.7 ± 1.1 | - | - | - |
| Kosakonia pseudosacchari Z2WD1 | - | 2.1 ± 0.4 | 14.2 ± 0.3 | 3.73 ± 0.2 | 1 ± 0.4 | 5.7 ± 0.3 | 1 ± 0.2 | - | 1 ± 0.4 | - | 1 ± 0.2 | - | 2 ± 0.6 | 4.6 ± 0.2 | 1 ± 0.8 | - | 1 ± 0.2 | - | - |
| Phytobacter diazotrophicus Z2WL1 | - | 1 ± 0.3 | - | 48.1 ± 0.9* | 2 ± 0.5 | 12.7 ± 0.7* | 1 ± 0.4 | 23.5 ± 0.4* | 2 ± 0.5 | 4.8 ± 0.7 | 2 ± 0.5 | - | 4 ± 0.9 | - | - | - | - | 23.6 ± 0.5* | - |
| Pseudomonas protegens E1BL2 | - | 1 ± 0.2 | - | 4.33 ± 0.4 | 3 ± 0.3 | - | 3 ± 0.5 | - | 3 ± 0.4 | - | 4 ± 0.4 | - | 4 ± 0.6 | - | 3 ± 0.5 | 3.3 ± 0.6 | 3 ± 0.7 | - | + |
| Pantoea sp. E2AD2 | - | 2.8 ± 0.5 | 29.3 ± 0.5* | 32.1 ± 0.5* | 4 ± 0.8 | 3.6 ± 0.6 | 3 ± 0.3 | - | 3 ± 0.6 | - | 3 ± 0.4 | 3.9 ± 0.6 | 3 ± 0.4 | - | 3 ± 0.3 | - | 3 ± 0.6 | - | - |
| Pantoea ananatis E2HD8 | - | 1.2 ± 0.1 | 10.6 ± 0.3 | 51.7 ± 0.9* | 1 ± 0.3 | - | 2 ± 0.1 | 5.7 ± 0.6 | - | - | 1 ± 0.5 | - | 1 ± 0.3 | - | - | - | 1 ± 0.3 | 8.4 ± 0.6 | - |
| SynCom 1 | - | 2.4 ± 0.4 | 69.1 ± 0.6** | 194.3 ± 1.2** | 4 ± 0.7 | 25.3 ± 0.6** | 2 ± 0.3 | 25.6 ± 0.6** | 3 ± 0.5 | 29.1 ± 1.8** | 2 ± 0.4 | 10 ± 0.7* | 2 ± 0.4 | 41.6 ± 1.2** | 2 ± 0.4 | 23 ± 2.5* | 3 ± 0.3 | 31.5 ± 1.2** | + |
| SynCom 2 | - | 2.6 ± 0.4 | 79.1 ± 0.5** | 188 ± 0.8** | 3 ± 0.5 | 18.3 ± 0.4* | 1 ± 0.2 | 6.7 ± 0.3 | 3 ± 0.6 | 89.8 ± 1.6*** | 2 ± 0.8 | 75 ± 0.8*** | 2 ± 0.8 | 34 ± 3.6* | 3 ± 0.5 | 3.4 ± 0.7 | 2 ± 0.6 | 18.4 ± 0.8* | + |
| SynCom 3 | 32.8 ± 12.1 | 3 ± 0.3 | 117.2 ± 0.9*** | 210.6 ± 1.1** | 2 ± 0.6 | 87.2 ± 0.9*** | 3 ± 0.1 | 75.0 ± 1.4*** | 3 ± 0.6 | 40.9 ± 0.6** | 3 ± 0.9 | 40.9 ± 2.5** | 3 ± 0.5 | 75.6 ± 0.8*** | 2 ± 0.4 | 80.8 ± 2.7*** | 4 ± 1.2 | 53.9 ± 2.8*** | + |
The features of bacterial isolates and SynCom were compared using Duncan's test (*p ≤ 0.05, **p ≤ 0.01, and ***p ≤ 0.001). The values are expressed as the mean ± SD (n = 3). IAA, indole acetic acid; BNF, biological nitrogen fixation; ACC, 1-aminocyclopropane-1-carboxylic acid; Fe, iron; Mg, magnesium; V, vanadium; Mo, molybdenum; Zn, zinc; Ca, calcium; Cu, copper.