Effects of Plant Density on Yield of Different Oilseed Sunflower Hybrids

A field experiment was carried out to study the effects of plant densities on grain yield of different growth period of oilseed sunflower hybrids in Shenyang in 2008.The experimental design was randomized complete block with 3 replications.The treatments were four sunflower hybrids and five planting densities.The results indicated that the potential of grain yield was change with different vegetation period sunflower hybrids.The grain yield in order was F53F51F57S40 in the same sowing date.Plant density had significant effect on grain yield of sunflower hybrids.The different vegetation period sunflower hybrids obtain the highest yield with suitable density.Suitable densities of short vegetation period sunflower hybrid were more than the suitable densities of long vegetation period sunflower hybrid.