NPK accumulation and translocation in dryland winter wheat cultivars with different yields

To evaluate the differences in NPK accumulation and translocation in dryland winter wheat cultivars with different yields, nine winter wheat cultivars were planted on field with no fertilizer application for six years. The results showed significant differences in NPK accumulation, translocation and K loss for different cultivars. Before anthesis, increased fertilizer rate led to more rapid increase in N accumulation in high-yield cultivars than in medium- and low-yield cultivars. At pre-anthesis, however, there were no significant differences in P accumulation among different-yield wheat cultivars. High-yield cultivars were characterized as high post-anthesis N and P accumulation and low K loss levels. This was due to high ability to save translocated K in wheat grains. Also in high-yield cultivars, N and P translocation and remobilization efficiencies, and the contribution of remobilized N and P to grain yield were lower than those in low-yield cultivars. However, there was no obvious difference in K accumulation and translocation at pre-anthesis. Consequently, higher post-anthesis N and P accumulation and lower K loss were important driving factors of higher grain yields in dryland wheat cultivars.