Importance of Industrial Waste in Maximizing the Yield of Rice and Its Effect of Soil Fertility in Coastal Region

Abstract

A field experiment was conducted in the coastal region of Ramanathapuram district in Tamil Nadu to maximize the rice yield through integrated nutrient management and its effects on soil properties. There were four sources of amendments, viz., Gypsum as per the gypsum requirement, 2.3 t ha-1), Biocompost (5 t ha-1), Vermicompost (5 t ha-1) and Composted coir pith 10 t ha-1 used with a test crop of rice (var. ADT 45) during Rabi season of 2007-08 with 12 treatment combinations. The results revealed that the addition of recommended dose of fertilizer plus azophos at 2 kg ha-1 plus gypsum plus biocompost at 5 t ha-1 significantly increased the straw and grain yield of rice (7146.14 kg ha-1 and 4306.54 kg ha-1, respectively). Recommended dose of fertilizer plus azophos at 2 kg ha-1 plus gypsum 2.3 t ha-1 plus biocompost at 5 t ha-1 recorded the highest N, P, K uptake by grain and straw. The increased availability of nutrients in post harvest soil were observed in organics applied plots and the highest values of available macro nutrients, viz., N (146.76 kg ha-1), P (17.13 kg ha-1) and K (152.81 kg ha-1) and micro nutrients, viz, Fe (6.23ppm) and Zn (0.37ppm) was observed in the treatments received under biocompost at 5 t ha-1 and vermicompost 5 t ha-1.  Similarly more microbial population, viz., bacteria (31.81x106/g of soil), fungi (10.11 x103/g of soil) and actinomycetes (6.48 x103/g of soil) was observed in soil were the treatment received the RDF plus azophos at 2 kg ha-1 plus gypsum 2.3 t ha-1 plus biocompost at 5 t ha-1.