Integrated effect of organic manures and inorganic fertilizers on soil phosphatase activity and yield of maize-spinach cropping system

Integrated use of organic manures and inorganic fertilizers were evaluated for soil health, crop response and economic feasibility of their use in maize-spinach cropping system. Among the different combinations application of 75% RDF + 25% through vermicompost recorded significantly highest grain and stover yield (52.38, 60.77 q ha⁻¹). The spinach crop was grown during summer responded favourably to the residual and cumulative treatments and the highest fresh leaf yield (14.68 and 12.37 t ha⁻¹) was recorded in cumulative and residual treatments. The soil phosphates enzyme activity at different growth stages of maize and at final harvest of spinach revealed that there was increase in enzyme activities upto active growth stages of crops and later showed a decrease. Significantly highest acid and alkaline phosphatase 37.93 and 68.43, 49.30 and 89.64 and 26.87 and 71.27 ìg of PNP g⁻¹ soil h⁻¹ activity was found in treatment T₄ (100% VC) at vegetative, tasseling and at harvesting stage of maizeThe cumulative and residual effects of spinach revealed that the phosphatase activity was higher in cumulative treatments than residual treatments.