Table 2.
Symbiotic efficiency of native rhizobia isolates inoculated on cowpea plants and their effect on nodule number, shoot, root and nodule dry weight.
| Isolate | Nodule Number | Nodule Dry Weight (g plant−1) | Shoot Dry Weight (g plant−1) | Root Dry Weight (g plant−1) | Symbiotic Efficiency (%) |
|---|---|---|---|---|---|
| M1 | 4.50(4.50)c | 0.01(0.01)bc | 0.13(0.03)d | 0.07(0.02)c | 12.85(2.90)d |
| M2 | 38.50(9.98)ab | 0.22(0.09)a | 0.85(0.08)ab | 0.30(0.03)a | 82.49(7.64)ab |
| M3 | 46.00(7.25)a | 0.08(0.02)abc | 0.75(0.07)ab | 0.16(0.01)abc | 72.76(6.38)ab |
| M5 | 2.50(2.50)c | 0.00(0.00)c | 0.17(0.04)d | 0.16(0.05)abc | 16.49(4.26)d |
| M6 | 21.25(8.75)bc | 0.11(0.04)abc | 0.49(0.07)bcd | 0.09(0.01)bc | 47.59(7.08)bcd |
| M11 | 6.25(2.43)c | 0.01(0.00)bc | 0.21(0.03)d | 0.16(0.00)abc | 20.77(2.76)d |
| M17 | 8.50(4.97)c | 0.02(0.01)bc | 0.25(0.06)cd | 0.08(0.02)c | 24.76(5.85)cd |
| M18 | 3.50(3.50)c | 0.01(0.01)c | 0.18(0.04)d | 0.17(0.02)abc | 17.06(3.82)d |
| M20 | 4.50(4.50)c | 0.01(0.01)bc | 0.21(0.05)d | 0.13(0.05)abc | 20.27(4.97)d |
| REF | 34.50(9.10)ab | 0.14(0.07)ab | 0.70(0.15)abc | 0.22(0.04)abc | 67.68(14.60)abc |
| PC | 0.00(0.00)c | 0.00(0.00)c | 1.03(0.34)a | 0.29(0.11)ab | 100.00(32.61)a |
| NC |
0.00(0.00)c |
0.00(0.00)c |
0.24(0.03)cd |
0.09(0.03)bc |
22.86(3.25)cd |
| P value | p < 0.0001 | p < 0.0001 | p < 0.0001 | p = 0.0006 | p < 0.0001 |
Values followed by the same letters within the column are not significantly different from each other according to Tukey's Honest Significant Difference (HSD) at 5 % level. NC-Non inoculated plants, REF- Rhizobia reference strain (Bradyrhizobium sp. strain USDA 3456), PC-un-inoculated control plants supplemented with nitrogen (0.05 % KNO3). SE % = (Total dry weight of inoculated plant/Total dry weight of PC-un-inoculated control plants) x 100. Standard error is indicated in parentheses.