Response of Mycorrhiza,Organic Sources,Secondary and Micro Nutrients on Soil Microbial Activities and Yield Performance of Colocasia (Colocasia esculenta L.) in Alfisols

Response of the integrated use of mycorrhiza, inorganic and organic manures on microbial variables and yield performance of colocasia (Colocasia esculenta L.) was studied in an acid Alfisol. Significantly highest mean cormel yield (14.13 t ha^?1) was recorded due to application of super optimal doses of nitrogen, phosphorus, and potassium (NPK). Integrated application of lime + farmyard manure (FYM) + ½ NPK + zinc sulfate (ZnSO₄) has recorded the highest dehydrogenase activity (2.048 µg TPF hr^?1 g^?1) and Fluorescein Diacetate Hydrolysis assay (1.855 µg g^?1 hr^?1). The highest acid and alkaline phosphatase activities (77.67 and 51.18 µg PNP g^?1 h^?1, respectively) were observed due to Vesicular Arbuscular Mycorrhiza (VAM) inoculation in combination with lime + FYM + ½ NPK. Dehydrogenase and phosphatase activities had a highly significant relationship with cormel yield and the biochemical constituents of colocasia. The study emphasized the conjunctive use of balanced inorganic fertilizers and organic manures to enhance the enzymatic activities and to realize higher crop yields of colocasia in acid Alfisols.