In vitro Evaluation of Antagonists against Fusarium oxysporum f. sp. ciceris Causing Wilt in Chickpea
Mahima Choudhary *
Department of Plant Pathology, R.A.K. College of Agriculture, Sehore, RVSKVV, Gwalior (M.P.), India.
D. R. Saxena
Department of Plant Pathology, R.A.K. College of Agriculture, Sehore, RVSKVV, Gwalior (M.P.), India.
*Author to whom correspondence should be addressed.
Abstract
Chickpea wilt, caused by Fusarium oxysporum f. sp. ciceris, is a soil- and seed-borne disease that can reduce crop productivity. This study assessed the in vitro antagonistic activity of three Trichoderma treatments and three bacterial bioagents against the causal pathogen. The bioagents comprised Trichoderma harzianum strain 1, T. harzianum strain 2, T. viride, Pseudomonas fluorescens, P. diminuta and Bacillus subtilis. Seven treatments, including an untreated control, were evaluated in a completely randomised design with three replications. Using the dual-culture technique, the radial growth of F. oxysporum f. sp. ciceris was measured on the third, fifth and seventh days of incubation. Percentage inhibition was calculated relative to the untreated control. On the seventh day, pathogen radial growth in the control was 45.00 mm. No measurable pathogen growth was recorded in the P. fluorescens and B. subtilis treatments, corresponding to 100% inhibition under the assay conditions. T. viride produced 74.82% inhibition, followed by P. diminuta (66.66%), T. harzianum strain 1 (55.55%) and T. harzianum strain 2 (38.53%). The differences among treatments indicate variation in laboratory antagonistic performance, with the two bacterial treatments showing the greatest inhibition and T. viride performing best among the tested fungal treatments. These findings identify bioagents for further assessment in chickpea-based experiments. However, inhibition observed on culture medium should not be interpreted as direct evidence of wilt control in plants.
Keywords: Chickpea, Cicer arietinum, biological control, dual-culture assay, Fusarium oxysporum f. sp. ciceris, Fusarium wilt, Trichoderma viride, Pseudomonas fluorescens, Bacillus subtilis, mycelial growth inhibition