Study on Density Tolerance of Maize Varieties and Thingking on Density Tolerant Breeding

The maize yield of U.S.A was much higher than that of China by increasing planting density.Gradually increasing the planting density was the main way for increasing maize yield the inevitable development trend of maize production.Using the commonly used maize varieties in the field production Zhengdan 958,Xianyu 335 and Hengdan 6272 as the experimental materials,the effects of different planting densities on the yield were studied.The results showed that with the increasing of planting density,the yield of different maize varieties showed different change trend.The density tolerance of popularized maize varieties should be further improved.The density tolerant varieties breeding and the hybrid identification technology were discussed.