Microbial inhabitants of agricultural land have potential to promote plant growth but they are liable to traditional practice of wheat (T. aestivum L) straw burning

Abstract

Abstract Soil organic carbon (SOC) is closely associated with the soil fertility level. Crop straw return is an important conservation agricultural practice to restore SOC in the soil. Soil microbial communities are actively involved in decomposition of crop straws. Decomposition of straws releases bonded nutrients, water, organic carbon and energy in the soil, which enhance plant growth as well as increase microbial biomass. This study was conducted to analyze the effect of the conventional practice of wheat straw burning on bacterial populations present in the soil shortly after crop harvesting. Results indicate that wheat cultivated soil is inhabited by many plant growths promoting bacterial genera like Acinetobacter, Azotobacter, Bacillus, Lysinibacillus, and Raoultella, however, vegetation fire has dramatically decreased number of bacterial cells in the soil. Plant growth promoting assessment indicates that isolated strains have the greatest potential to boost plant growth. For example, some isolates have remarkable ability to synthesize auxin under in-vitro conditions like B. safensis AB-81, and B. thuringiensis AM-16 and some are able to solubilize inorganic phosphate, for instance, A. pittii AM-12 and B. aryabhatti AB-51. The rooting assay has shown that bacterial isolates had significantly improved plant growth. It is concluded that wheat cultivated land is inhabited by several beneficial bacterial communities while the straw burning practice has a strong negative impact on soil bacterial count.