Effect of nitrogen and weed-control practices on performance of irrigated direct-seeded rice (Oryza sativa)

Abstract

A field experiment was conducted during rainy (kharif) season of 2002 and 2003 at Faizabad in silty loam soil to study the effect of nitrogen and weed-control measures on weed growth and yield of direct-seeded rice (Oryza sativa L.). There was significant increase in grain and straw yields as well as yield attributes, viz. panicles/m2 and test weight, with every increase in dose of N up to 120 kglha. The weed-control treatments significantly de- creased the weed population, dry weight of weeds and weed index and increased the weed-control efficiency, panicleslm2, grain yield and straw yield compared with the unweeded check. Application of anilofos @ 0.4 kg/ha + one hand-weeding at 30 days affer sowing remained on a par with that of weed-free treatment for all the pa- rameters, recording grain yield of 5.13 tlha and weed-control efficiency of 85.27%. Weed infestation reduced the grain yield by 64.42 and 64.41% and removed N up to 63.94 and 53.27 kglha under unweeded check during the first and second year, respectively. There was response up to 120 kg Nlha in the well-managed weed-control plots.