Effects of Conservation Agricultural Practices on Soil Microbial Population and Yield of Cotton.

Field investigations were conducted to assess the effect of conservation agricultural practices on soil biological properties and yield of cotton during the kharif season of 2018 and 2019. The experiments were laid out in a split plot design with four main factors viz., conventional tillage with irrigation schedule of 0.8 IW/CPE ratio (M₁), conventional tillage with irrigation schedule of 0.6 IW/CPE ratio (M₂), minimum tillage with irrigation schedule of 0.8 IW/CPE ratio (M3) and minimum tillage with irrigation schedule of 0.6 IW/CPE ratio (M4). Sub plot had six treatments of weed and nutrient management viz., crop residue mulch with 100% RDF (S₁), crop residue mulch with 75% RDF (S₂), pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S₃), pre-emergence application of pendimethalin fb one hand weeding with 75% RDF (S₄), mechanical weeding twice with 100% RDF (S₅) and mechanical weeding twice with 75% RDF (S₆). Total microbial populations viz., bacteria, fungal, and actinobacteria were higher in cotton rhizosphere soil with the minimum tillage of irrigation at 0.8 IW/CPE ratio (M₃) in the main plot treatments. Cotton rhizosphere soil with crop residue mulch with 100% RDF (S₁) recorded a higher microbial population and it was statistically similar with pre-emergence application of pendimethalin fb one hand weeding with 100% RDF (S₃) in the sub plot treatments. Among the treatment combination, minimum tillage with irrigation at 0.8 IW/CPE ratio (M₃) and crop residue mulch with 100% RDF (S₁) recorded a higher microbial population. Similarly, a higher seed yield of cotton was also recorded with minimum tillage and irrigating the crop at 0.8 IW/CPE ratio and pre-emergence application of pendimethalin fb one hand weeding along with application of 100% RDF (M3S3). [ABSTRACT FROM AUTHOR]