Biocontrol activity of Bacillus, Paenibacillus and Pseudomonas against Fusarium wilt of chickpea in Morocco

Fusarium wilt caused by Fusarium oxysporum f.sp ciceris is one of the major diseases impacting chickpea productivity. Significant losses are reported by farmers due to the absence of effective wilt management options. Biological control using beneficial microorganisms in agriculture, is one of the promising alternatives and eco-friendly strategies utilised to overcome this disease. The present study investigated the biocontrol effect of 40 bacterial strains isolated from the rhizosphere of healthy chickpea plants collected from major chickpea growing regions in Morocco. Twelve out of 40 strains showed more than 25% in vitro inhibition of the pathogen growth. These strains, using the 16S rDNA gene sequencing, were classified into three genera, namely Bacillus, Paenibacillus, and Pseudomonas, represented by different species. Our finding showed that the mode of antagonism was mainly due to the production of diffusible and volatile compounds as well as lytic enzymes. Moreover, a greenhouse experiment of the three selected antagonistic strains showed a significant reduction in the mean of wilt incidence in different chickpea genotypes, StrainB18 reduced the wilt incidence in the susceptible variety from 90% to 18% Consequently, our antagonistic bacterial strains could be a potential component of integrated management of Fusarium wilt, therefore, increase the yield of chickpea.