BACTERIA OF THE CHICKPEA RHIZOSPHERE WITH ANTAGONISTIC CAPACITY TO PHYTOPATHOGENOUS FUNGI AND PLANT GROWTH PROMOTION

Abstract

The disease known as "chickpea rabies", caused by Fusarium oxysporum, Fusarium solani and Rhizoctonia solani, is one of the main limitations of chickpea production in Mexico. Traditionally, chemical control has been used, which has negative impact on agroecosystems. Biological control is an ecological alternative for the management of plant diseases by the use of antagonistic bacteria and fungi. The objective of the present investigation was to isolate and identify rhizobacteria of chickpea plants with in vitro antagonistic capacity towards F. oxysporum, F. solani and R. solani and plant growth promotion. The ability of the isolates to produce siderophores, gibberellic acid and solubilize phosphorus was evaluated. Sixty-seven bacterial isolates were obtained, of which two (AG-B007 and AG-B038) were selected because of strong in vitro antagonism towards F. oxysporum, F. solani and R. solani. These isolates presented siderophore production in CAS medium, solubilization of inorganic phosphorus in ranges of 164 to 171 μg mL-1 and gibberellic acid in values of 29 to 55 μg mL-1. The inoculation of the AG-B007 and AG-B038 isolates promoted growth in chickpea plants under greenhouse conditions. The two isolates were identified as belonging to the genus Bacillus by sequencing the 16S RNAr gene.