Influence of graded levels of nitrogen and micronutrient enriched compost on dehydrogenase and phosphatases activity of aerobic rice (Oryza sativa L.)

Abstract

A field experiment was conducted during Kharif 2011 at ZARS, V.C. Farm, Mandya, Karnataka, Influence of graded levels of nitrogen and micronutrient enriched compost on Dehydrogenase and Phosphatases activity of aerobic (Oryza sativa L.). The experiment was carried out in a randomized complete block design (RCBD) replicated thrice with 17 treatments involving levels of nitrogen and micronutrient enriched compost. The soil of experimental field was sandy loam in texture having a neutral pH of 6.68 with low soluble salts (EC = 0.02 dSm–1), low in organic carbon content (4.66 g kg–1), medium in available N (376.72 kg ha–1), medium in available P2O5 (33.18 kg ha–1), medium in available K2O (298.91 kg ha–1), low in available S (9.91 mg kg–1), DTPA extractable zinc (0.51 mg kg–1) and iron (4.52 mg kg–1). The study confirmed that the Dehydrogenase activity in soil at panicle initiation stage was significantly higher in the treatment (T17: 241.77 μg TPF g-1h-1) which was on par with (T16: 240.63 μg TPF g-1 h-1) and (T15: 232.84 μg TPF g-1h-1) as compared to control (T1: 229.03 μg TPF g-1h-1). Phosphatase activity in soil at panicle initiation stage was significantly higher in the treatment (T17: 191.57 μg PNP g-1h-1) followed by (T16: 186.63 μg PNP g-1h-1) and (T15: 183.30 μg PNP g-1h-1) as compared to control (T1: 178.73 μg PNP g-1h-1).