Investigation on possibility of biological control of Fusarial wilt of chickpea by antagonistic microorganisms in situ

Wilt of chickpea caused by Fusarium oxysporum and F. solani is one of the most important disease of this crop in the country. In this investigation, efficacy of 5 bacterial isolates, 2 isolates of antagonistic fungi and a fungicide was evaluated against this disease. The results of this study reveal that :1) among adhesive materials, methyl cellulose, carboxy methyl cellulose and starch caused considerable increase in population of antagonistic organisms on seed coat, 2) in gradual drying of seeds (20 °C for 4 hrs) the population of antagonists was much higher than the seeds drying in 30 °C for 15 minutes, 3) storage of treated seeds with antagonists at 4 °C is more desirable than room temperature. Field experiments were conducted with 10 treatments and 4 replications under randomized complete blocks design in 5 provinces with coating of seeds with antagonists or dorect application of antagonists to the soil. Due to unfavorable climatic conditions (drought) in some provinces, specially in Kordestan province, the experiments faced failure and no results were obtained. However, with refrence to the obtained results with coating of seeds with antagonists, factorial analysis of infested plants percentage (in 4 localities) and yield (in 3 localities) revealed that there was significant differences among treatments at 1% level. Hight infestation (21.78%) was recorded in control check (infested) and the least in T.h., B30, B31, control check and fungicide treatments with 9.024, 9.67, 11.60, 12.03 and 13.68 percent infestation respectively. Higher yields were observed in control check (healty) with 841.40 kg/ha, in T.h. 830.6 kg/ha, in fungicide treated yield was 730.24 lowest yield was recorded in control check (infested) treatment with 459.47 kg/ha. In other set of experiments (i.e. addition of antagonists to the soil), the factorial analysis of percentage of infested plants and yield revealed that there were significant differences between treatments at 1% level. Highest infestation (30%) was recorded in control check (infested) and lowest in control check (healty) with 5.5% infestation, T.v. (18.25%), fungicide (18.25%) and T.h. (18.5%) treatments. High yield was recorded in T.h. (759.7 kg/ha) and control check (healty) 725.4 kg/ha and lowest (320.1 kg/ha) was recorded on control check (infested) treatment.