Response of medicinal rice (Oryza sativa L.) cv njavara to SRI and other management systems

Abstract

Field experiments were conducted at Cropping Systems Research Center, Karamana, Thiruvananthapuram, Kerala, during the summer seasons of 2007 and 2008 (January to April) to study the response of medicinal rice (Oryza sativa L.) cv Njavara to nutrient sources under different management systems like SRI, ICM, PoP of KAU and Farmers’ practice. The experiment was laid out in split plot design with four replications. The treatments consisted of four management systems viz., SRI (M1), ICM (M2), PoP (M3) of KAU and Farmers’ practice (M4) in main plots. Nutrient sources viz., organic sources (S1), integrated sources (S2) and inorganic sources (S3) were the sub plot treatments. Growth components viz., plant height, number of leaves hill-1, leaf area index (LAI), leaf area duration (LAD), culm strength, number of tillers m-2, root dry matter production hill-1 and flag leaf area were recorded. The data on yield attributes like number of productive tillers m-2, panicle length, number of grains panicle-1, number of filled grains panicle-1, 1000 grain weight, harvest index, sterility percentage, dry matter partitioning, paddy grain ratio, grain husk ratio were also worked out. Yield and uptake of nutrients (N, P, K,S Fe, Mn and Zn by grain, straw and crop (grain + straw) were also recorded. Biochemical components such as total free amino acids, phenols, starch, amylose, amylopectin and crude protein content of grain were estimated. Data on weed dry matter production and weed flora and crop duration in the treatments were also recorded. Soil enzymes (urease, phosphatase and dehydrogenase) and soil fertility status were assessed after the harvest of the crop.