Management of gray mold of chickpea, Botrytis cinerea with bacterial and fungal biopesticides using different modes of inoculation and application

Abstract

Biological control of Botrytis gray mold (BGM, Botrytis cinerea) of chickpea by foliar, seeds or soil treatments of seven biocontrol agents (BCA) isolated from commercial biopesticides was evaluated. Foliar inoculation with BGM fungus caused disease of greater severity (82%) in comparison to soil (38%) or seed inoculation (42%) and reduced the plant dry weight and yield of chickpea cv. BG-256 by 23% and 29%, respectively. Soil or seed inoculation with the fungus reduced the plant dry weight (10–12%) and yield (13–16%). Greatest control of the disease was observed in the plants which were inoculated with BGM fungus and BCA through same method i.e. seed–seed, soil–soil, etc. Soil treatment of Trichoderma harzianum (PBAT-1 and Biowilt-X) significantly improved the yield of soil inoculated plants ( P ⩽ 0.05). Similarly seed treatment with T. harzianum decreased the disease severity and increased the yield by 8–13% over seed inoculated control ( P ⩽ 0.05). Foliar treatment of T. harzianum effectively checked the disease (39–41%) and improved the yield (19–22%) of foliar inoculated plants over the respective controls ( P ⩽ 0.05). T. harzianum PBAT-1, Trichoderma virens Sanjeevni and Pseudomonas fluorescens Biocomp-X were found to be the most effective biopesticide strains. Treatment of biopesticides resulted in substantial decreases in the population of BGM fungus, whereas the population of biocontrol agents increased in the presence of B. cinerea.