TABLE 3.
Determination of the number of B. cepacia BC11 cells or the amount of purified AFC-BC11 needed to control damping-off of cotton caused by R. solani
| Antifungal treatmenta | Emergence (%)b,d | Survival (%)c,d |
|---|---|---|
| No. of BC11 cells/seed | ||
| 0 | 10 | 0 |
| 102 | 40 | 0 |
| 103 | 100 | 30 |
| 104 | 100 | 60 |
| 105 | 100 | 95 |
| Amt (μg) of AFC/seed | ||
| 0 | 3 | 0 |
| 1 | 15 | 8 |
| 5 | 70 | 52 |
| 10 | 100 | 85 |
| 20 | 100 | 95 |
Cotton seeds were coated with the indicated number of BC11 cells or indicated amount of purified AFC-BC11 and then planted into R. solani-infested vermiculite.
Percentage of cotton seeds that germinated in 3 weeks. Values are the means from two independent experiments with 20 seeds for each treatment. Without R. solani, 100% germination was observed.
Percentage of seedlings living after 3 weeks. Values are the means from two independent experiments with 20 seeds for each treatment. Without R. solani, there was 100% survival.
Analysis of variance (statistical analysis package version 6.3 [SAS Institute]) indicated a significant correlation between the number of B. cepacia cells or the amount of AFC and both emergence (cells, P = 0.041 and R2 = 0.8; AFC, P = 0.012 and R2 = 0.88) and survival (cells, P = 0.007 and R2 = 0.94; AFC, P = 0.005 and R2 = 0.93).