Isolation, characterization, and evaluation of bacterial root and nodule endophytes from chickpea cultivated in Northern India.

Abstract

Endophytic bacteria from roots (12 isolates) and nodules (76 isolates) of chickpea legume grown under CCS Haryana Agricultural University farm were isolated. Among the endophytic bacteria, 50% from roots and 93.4% from nodules were Gram positive spore formers. Large number of endophytes from roots and nodules solubilized phosphate and produced ammonia. Isolate CRE3, and CNE215, were most efficient P solubilizers and. CRE12 and CNE76 being most efficient ammonia producer. Interestingly, few endophytic bacteria produced organic acid. Further selected 62 isolates were used to determine molecular diversity by RFLP of PCR amplified 16S rDNA. Endophytes from roots formed five separate clusters and nodule endophytes formed 13 clusters. Isolate CNE215 from nodules and CRE1 from roots possessed multiple beneficial traits and belonged two different clusters. These two isolates were identified after amplification and sequencing of 16S rRNA gene. Isolate CNE215 showed more than 98% similarity with partial sequence of 16S rRNA gene of Bacillus subtilis, whereas CRE1 showed more than 98% similarity with Bacillus licheniformis. Efficacy of these two strains was evaluated under field conditions and an increase up to 22.5% in grain yield over uninoculated control was observed with B. subtilis strain CNE215, whereas all the recommended biofertilizers were able to record an increase upto 14.4%.