Effects of Sulfur Application on Carbon and Nitrogen Transport and Grain Yield of High Yield Wheat Cultivars in Different Nitrogen Fertilizer Levels

Field experiments were conducted to investigate the effects of sulfur on carbon and nitrogen transport,grain yield and protein yield of two high yield winter wheat cultivars with different spike types.Two nitrogen levels(240 and 330 kg N· hm-2) were combined with two sulfur levels(0 and 60 kg S·hm-2) in the experiment.The results showed that:(1) compared with control,the ratio and amounts of transported storage carbon and nitrogen in the leaves,leaf sheaths,glumes and spike stalks could be increased with sulfur application.Moreover,the total ratios and amounts of transported storage carbon and nitrogen,and the contribution ratio of transported carbon and nitrogen could be increased before anthesis,and grain yield and protein yield were also increased significantly.(2)Grain yield and protein yield of two cultivars could be increased in all sulfur treatments,but' Yunong 949 'has higher grain yield and higher protein yield than that of 'Lankaoaizao 8',and grain yield of 'Yunong 949' was increased with 12.74% and 16.41%,respectively,and protein yield increased with 16.84% and 16.14%,respectively.As a result,it was shown that sulfur application could raise significantly the carbon and nitrogen transport,and could also increase the rate of nitrogen utilization and matter accumulation of plant,which resulted in the higher grain yield,but there were differences between two cultivars.