Effect of Establishment Techniques and Nitrogen Management on the Leaf Nitrogen Concentration (LNC), Flowering, Nitrogen Use Efficiency and Quality of Rice Hybrid (Oryza sativa L.) ADTRH1

摘要

Field experiments were conducted during the Kharif season 2002 and 2003 at wetland research farm of Tamil Nadu Agricultural University, Coimbatore with the objective of developing suitable and efficient crop establishment techniques and to optimize the nutrient management strategy for rice hybrid ADTRH1. The experiments were laid out in split plot design replicated thrice with four crop establishment techniques in the main plot and seven N management practices were assigned in the sub-plots. The results revealed that the Leaf Nitrogen Concentration (LNC) was not significantly influenced by the crop establishment methods. Wet seeded rice crop registered earlier flowering of seven days as compared to the transplanted crop. Nitrogen use efficiency recorded significantly higher value by the seeding through all the holes (M2) and it was on par with transplanting (M1) and seeding through one out of two holes (M3). Application of N based on Soil Test Crop Response (STCR) for a yield target of 7 t ha-1 registered significantly higher leaf nitrogen concentration and was comparable with N application in four splits plus green manure application @ 6.25 t ha-1. The Nitrogen use efficiency was significantly higher with the N application based on Leaf Colour Chart (LCC) cv.4 whereas least NUE was registered with STCR based N application as compared to rest of treatments. The N management exerted significant variation in days to 50% flowering in both the years. Maximum number of days to 50% flowering was noticed with STCR based N application and minimum number of days was invariably noticed in control. The crop establishment methods did not cause significant variation in the quality parameters of hybrid rice. Significantly higher protein content was recorded with N application based on STCR and it was comparable with green manure 6.25 t ha-1 plus N application in four splits. Application of 100% N as organic manures recorded significantly higher amylase 27.20% and the lowest amylase content was observed in N application based on STCR.