Soil Enzyme Activities under Different INM Pr...

Soil Enzyme Activities under Different INM Practices in Kharif Rice (Oryza sativa L.)

Author Name : K. Shanthi, P. Chandrasekhar Rao

ABSTRACT A study was conducted to find out the influence of integrated nutrient management practices on soil enzyme activities in Kharif rice. The experiment was conducted at farmer’s field, Devaryamjal village, near Hakimpet, Rangareddy district, Telangana. The experiment was laid out in randomized block design (RBD) with 11 treatments, each replicated 3 times. The treatments consisted of control (T1), 100% RDFN (T2), 75% RDFN + 25% N through VC, PM and FYM (T3, T6, T9), 50% RDFN + 50% N through VC, PM and FYM (T4, T7, T10), 100% RDN through VC, PM and FYM (T5, T8, T11). The enzyme activities increased with age of crop and reached peak values at 60 DAT, decreased later on and returned to initial values at harvest.Among the different treatments, treatment T5 (100% RDN – VC) recorded maximum enzyme activities i.e., Urease (28.86 mg of NH4 + -N released 5g soil-1 2h-1 ), Dehydrogenase (4.64 mg of TPF produced g soil-1 d -1 ), Acid phosphatase (191.3 µg of p-nitrophenol released g soil-1 h -1 ), Alkaline phosphatase (568.2 µg of p-nitrophenol released g soil-1 h -1 ) when compared to rest of the treatments with minimum values recorded with treatment T1 (Control). Soil enzymatic activity acted as useful indicator of soil fertility dynamics