Abstract

A field experiment was conducted on a sandy loam soil during rabi (maize) and summer (spinach) seasons of 2009–10 with a view to study the effect of organic manures, inorganic fertilizers and their integration on soil dehydrogenase activity and yield of maize-spinach cropping system. Among the different combinations application of 75% RDF+25% through vermicompost recorded significantly highest grain and stover yield (52.38 and 60.77 q/ha) at harvest but on par with 75% RDF+25% through poultry manure and 75% RDF+25% through FYM. The spinach crop grown during summer responded favourably to the residual and cumulative treatments and the highest fresh leaf yield (14.68 and 12.37 t/ha) was recorded in cumulative and residual treatments. The soil dehydrogenase enzyme activity at different growth stages of maize and at final harvest of spinach revealed that there was increase in enzyme activities up to active growth stages of crops and later showed a decrease. Significantly highest dehydrogenase activity was found in treatment T4 (100% VC) with a value (163.7), tasseling (180.3) and harvesting stage (136.9) μg of TPF produced/g soil/day at vegetative, tasseling and at harvesting stages of maize, which was on par with T8 and T11 and was significantly different from other treatments in maize crop. The cumulative and residual effects of spinach revealed that the dehydrogenase activity was higher in cumulative treatments than residual treatments.