Rice cultures and nitrogen rate effects on yield and quality of rice (Oryza sativa L.)

Field studies in 2010 and 2011 were conducted to evaluate the effect of variable nitrogen rates (0-100 kg N ha-1) and culture methods (transplanted and direct) on chlorophyll contents, yield, grain quality, and economics in rice crop (Oryza sativa L. 'Basmati-385'). Transplanted rice gave a significantly higher paddy yield of 19.18% versus direct-seeded crop. Nitrogen application at 100 kg N ha-1 provided a maximum paddy yield (4.39 and 4.67 t ha-1) in both years. The rice kernel characteristics were also affected by culture methods and nitrogen levels. In addition, return variable cost in the transplanted rice increased by 22.27% over direct-seeded rice. Regarding quality, the amylose (24.35%) and protein (8.56%) contents were also higher in transplanted rice as compared to direct seeding at 100 kg N ha-1 application. The lowest amylose contents were recorded in N0 (23.55%) and N1 (23.69%) treatments, and amylase contents were also found lower in N0 and N1 in the direct seeding method. The nitrogen rate and cultures method also affect the chlorophyll contents positively in transplanted plants at higher level of nitrogen. From the results, it is concluded that under the climatic conditions of Faisalabad, Pakistan, higher paddy yield and yield components, as well as greater economic benefits, can be obtained for the transplanted method at 100 kg N ha-1 nitrogen application as compared to the direct seeding method.