1. INFLUENCE OF BIOINOCULANTS ON PHOSPHATASE ENZYME ACTIVITY IN SOIL UNDER DRIP FERTIGATION IN SUGARCANE CULTIVATION by R. SELASTIN ANTONY1, S. SATHIYARAJ2 AND S. KARTHIKEYAN1

Abstract

The study entitled “Influence of bioinoculants on phosphatase enzyme activity in soil under drip fertigation in sugarcane cultivation” is done to analyse the impact of bioinoculants (Azospirillum, Phosphobacteria and Potash solubilizers) and different irrigation levels on alkaline phosphatase activity and thereby soil fertility. In this study sugarcane variety CO 86032 was used with different levels of irrigation(75%, 100%, 125% Recommended dose of irrigation) and fertigation (75% and 100% Recommended dose of fertilizers with different formulations of fertilizers and with or without biofertiliers). Biofertilizers were applied at 30, 60 and 90 DAP. Based on the results obtained from the field trial, Application of 125 percent ETc (I₃) showed  maximum phosphatase activity and 75 percent + LBF (F₃) recorded the highest phosphatase activity Interaction effect of 125 percent ETc with 75 percent RDF as fully water soluble fertilizer + LBF (I₃F₅) recorded the highest phosphatase activity. Phosphatase activity correlated closely with soil temperature, soil water content, and pH and also incorporation of liquid biofertilizer through the drip fertigation increases the phosphatase activity.