Effect of poly (γ-glutamic acid) on wheat productivity, nitrogen use efficiency and soil microbes

Abstract

Recently, with numerous environmental problems being caused by chemical fertilizer overuse, agricultural practices are shifting toward the development of environmentally friendly N fertilizers.In this study, pot and field experiments were simultaneously conducted to investigate the effect of poly (-glutamic acid) (-PGA) on the yield, N use efficiency, and soil microenvironment of wheat.Our study demonstrates a statistically significant increase in winter wheat, number of tillers, seed number per spike, yield, soil microbial biomass N (SMBN), and soil enzymes after -PGA application.The highest grain yield of 7435.69 55.91 kg ha -1 was obtained after -PGA application in the field experiment, which was 7.17% higher than the urea control.The N recovery efficiency increased by 11.81%-14.00%and 11.30%-11.38%after the application of -PGA in pot and field experiments, respectively.More mineral nitrogen in soil was immobilized by the microbes after -PGA application at the early growth stage of wheat.The immobilized nitrogen was gradually released at the late growth stage.The results demonstrate that -PGA can be used as a fertilizer synergist.