Impact of zinc and plant growth-promoting bacteria on soil health as well as aboveground biomass of desi and kabuli chickpea under arid conditions

BACKGROUND: Zinc (Zn) deficiency and low soil fertility are the major factors responsible for low yield in chickpea. This study was conducted to evaluate the effect of Zn application and plant growth-promoting bacteria (PGPB) (endophyte Enterobacter sp. MN17) on soil health and aboveground biomass of desi and kabuli chickpea under natural field conditions. Zn was applied as seed priming (0.001 mol L−1) and soil application (10 kg Zn ha−1) with and without PGPB. To determine the impacts of Zn and PGPB on soil biological health, soil microbial biomass carbon (MBC) and soil extracellular enzyme activities were analyzed at two growth stages: vegetative (90 days after sowing) and maturity (163 days after sowing). RESULTS: The highest aboveground biomass (5.1 t ha−1) was recorded with Zn seed priming + PGPB in kabuli chickpea and in desi chickpea (4.8 t ha−1) with Zn seed priming only. The application of Zn significantly increased soil MBC, which was higher in kabuli (795 and 731 μg C g−1) compared to desi chickpea (655 and 533 μg C g−1) at both vegetative and reproductive growth stages, respectively. The highest extracellular soil enzyme activities, – β-glucosidase (4758 nmol g−1 h−1), acid phosphatase (5508 nmol g−1 h−1), chitinase (5997 nmol g−1 h−1) and leucine aminopeptidase (993 nmol g−1 h−1) – were recorded with Zn seed priming. Of the chickpea types, kabuli chickpea had higher soil extracellular enzyme activities in the rhizosphere than desi chickpea. CONCLUSION: Zn seed priming along with PGPB application may improve soil health and chickpea biomass in marginal soils. © 2021 Society of Chemical Industry.