Root zone soil temperature and microflora population in QPM as influenced by irrigation regimes and nutrient levels in new alluvial zone of West Bengal

Abstract

A field experiment was conducted on quality protein maize during rabi seasons of 2017-18 and 2018-19 at BCKV, West Bengal constituting three irrigation schedules viz. IW/CPE 0.5 (I1), 0.75 (I2) and 1.0 (I3) in main plots and four nutrient management practices viz. control (N1), 100% RDF (N2), 75% RDF + 2 t/ha vermicompost (N3) and 75% RDF + 2 t/ha vermicompost + 25 kg/ha ZnSO4 (N4) in sub plots in split-plot design with three replications. Results suggested that I3 recorded the lowest temperature at 15 and 20 cm soil depth at 60, 90 and 120 DAS (18.430C, 24.740C, 33.840C and 17.750C, 23.180C, 31.010C during 2017-18 and 18.760C, 23.940C, 29.410C and 18.030C, 22.120C, 27.480C during 2018-19 respectively). Nutrient application did not pose much influence on soil temperature but it affected microbial population significantly. Besides, I3N4 showed highest microflora population i.e. 248.00 and 247.00 CFU×106 total bacteria; 112.00 and 115.00 CFU×105 total actinomycetes and 8.67 and 12.67 CFU×104 total fungi during 2017-18 and 2018-19 at 60 and 90 DAS, respectively. The study shows that the pattern of microflora population was not affected significantly by soil temperature and I3N4 can be recommended for improving microbial communities in rhizosphere in new alluvial zone of West Bengal.