Response of Rice(Oryza saliva.L)Hybrids to N and K Under Transplanted Condition

摘要

Field experiments were conducted at 18 and 29 locations during kharif 2000 and 2001 respectively,to study the response of rice hybrids against local standard checks for nitrogen and potassium and grain yield.The interaction effect of N and K vs rice hybrids was significant at 8 locations viz.,Rajendranagar,Coimbatore,Varanasi,Raipur,Wangbal,Chakdaha,Karjat and Arundhatinagar during kharif 2000 and at 7 locations viz.,Coimbattore,Parbhani,Faizabad,Patna,Ranchi,Kanpur and Arundhatinagar during kharif 2001 indicating differential nutrient response for hybrids as compared to high yielding varieties(HYV's)at these locations irrespective of edaphic and climatic conditions.Among hybrids tested over the locations for their potential yield response to applied N and K,hybrid KRH-2 recorded higher mean grain yield(6.55 and 5.88 t ha~(-1))followed by PHB-71(6.41 and 6.01 t ha~(-1))with mean per cent grain yield increase of 31 and 26 than local check varieties(4.96 and 4.71 t ha~(-1))during kharif 2000 and 2001 respectively.As mean over the hybrids/checks,higher grain yield of 6.99 and 6.51 t ha~(-1)was obtained with T-10(N150+P60+K80 kg ha~(-1))in kharif 2000 and 2001 respectively.Mean over nutrient combinations,hybrid KRH-2 and PHB-71 showed higher nutrient response(12.79 & 15.56 and 12.44 & 15.42 kg grain/kg nutrient during kharif 2000 & 2001)as well as higher benefit :cost ratio of 2.19 than local checks.The economic response increased with increase of N from 90 to 150 kg ha~(-1)and K from 0 to 80 kg ha~(-1)indicating need for K application for enhancing grain yield of hybrids as well as HYVs.