Yield-affecting factors and cultivation of hybrid rice,"Ⅱ You 1259"

"Ⅱ You 1259" is an indica combination for middle-late rice hybrid bred by.The study on factors affecting yield for "Ⅱ You 1259" indicated that the spikelet number per panicle and yield positively and significantly correlated at 0.01 level;the seed setting rate and yield significantly correlated at 0.05 level;the panicle number and 1000 grain weight did not significantly correlate.The panicle number and spikelet number per panicle negatively and significantly correlated at 0.01 level.The results of path analysis indicated that direct path coefficients of spikelet number per panicle,panicle number,seed setting rate,1000 grain weight to the crop yield were 0.929 3,0.7349,0.5720 and 0.2920,respectively.To study the high-yielding cultivation methods for "Ⅱ You 1259," 4 factors were targeted(i.e.,planting density x1,age of transplanting leaf x2,nitrogen application rate x3 and potassium application rate x4)and optimized.The regression models of the 4 factors and yield were established.The results showed that the main influential elements for yield included the age of transplanting leaf,planting density and nitrogen application rate.After simulated screening and optimal selection using computer software,the optimized cultivation conditions for high rice yield were seedlings with 4.5～5.8 leaves for transplanting,planting density at 217500～295500 hills per hm2,N applied at a rate of 122.3～207.4 kg N per hm2 and K at 56.8～200.9 kg K2O per hm2.