Variation of Soil Microbial Growth and Enzyme Activities by Application of Treated Distillery Effluent in Maize Crop Grown Under Sandy Loam Soils

Abstract

A field experiment was conducted to investigate the soil microbial growth and enzymatic activity of Treated Distillery Effluent (TDE) and Bio-compost (BC) applied in sandy loam soils grown with Maize crop (Zeamays). Under split plot design with five main plots with addition of organics viz., No organics; application of TDE @ 0.5 lakh litres ha-1TDE @ 1.0 lakh litres ha; Bio compost @ 5 t ha-1 and FYM @ 12.5 t ha +biofertilizers. In addition, five subplot treatments viz., addition of inorganic fertilizers atdifferent levels of recommended dose of NP fertilizers (0 %, 50 %, 75 % and 100 %) compared with 100 per cent recommended dose of NPK @ 150 :75: 75 of kg N, P andK2O ha-1. Application of TDE 1.0 lakh litres ha-1 resulted higher bacterial, fungal and actinomycetes population over control at all stages of crop growth. Indeed, the soil bacterial population recorded the highest value of 20.1 and 19.3 x106 of soilwith the application of TDE @ 1.0 lakh litres ha-1 compared to control at post-harvest stage. There was an increase in the soil fungal population to the tune of 30.3 per cent over control at post-harvest stage. Furthermore, application of TDE @ 1.0 lakh litres ha-1 recorded the highest soil actinomycetes population at all stages of crop growth. The soil enzyme activities as phosphatase, dehydrogenase and urease recorded the highest values of12.8 µg p-nitrophenol g-1 soil hr-1; 2.96 µg TPF g-1 soil hr -1 and 5.16 µg NH4-N g -1 respectively with the application of TDE @ 1.0 lakh litres ha -1 . The soil microbial population and enzyme activities increased with the application of distillery effluent over control. Hence, it was observed that, Soil microbial activity had a direct impact on the plant nutrient availability as well as other favorable properties associated with soil productivity.