Effects of Planting Density and Sowing Date on Yield Formation of Hybrid Rice Guangliangyou 272

Effect of different planting density and sowing date on yield formation of Guangliangyou 272 were studied. The results showed that Guangliangyou 272 under cultivated density of 22.8 ×104hill / hm2 or its sowing date on April 15 had gain the highest yield. With the increase of plant density, tiller numbers peak value of rice and unavailable tiller were increased,Panicle number and grain number per spike were decreased. When sowing date was postponed, appearance date of tiller peak value was delayed, the unavailable tiller was increased and the number of grains per spike was reduced. Parabolic relationship existed between planting density and yield. So did with sowing date and yield. The rice production was up to 9611.7 kg / hm2 when its planting density was 25.8 ×104hill / hm2. When the rice was sown after the April 25 th, the yield was decreased. When it was sown early, the yield increased slightly. As a high-yield and late maturity hybrid rice varieties,Guangliangyou 272 is suitable to be sown in mid-April in Hubei Province or slightly in advance, with the planting densities around 25.8×104hill / hm2.