Effect of water deficit on mineral element absorption, distribution and water utilization by different wheat varieties

In the context of limiting the area of wheat irrigation, it is necessary for promoting resources use efficiencies, increasing yield and improving quality of wheat to explore nutrients absorption and utilization, and water use efficiency of wheat under water deficit condition. Pot experiments were conducted in phytotrons with three wheat varieties under two water conditions (normal and drought). The three wheat varieties included 'Cangmai-6001' (drought resistant), 'Hanmai-9' (wet and high yield) and 'Jimai-22' (multi-resistance and super high yield). The content, accumulation and distribution of mineral elements in different organs of the plants were measured. Also the relationship between these indexes with water use efficiency and yield analyzed. The results showed that the contents and accumulation of mineral elements were specific to different plant organs. The highest content and distribution ratio of Ca were observed in leaf, those of Cu and Zn were in grain, Na was in stem. Fe accumulated in different organs of the plant was influenced by water and plant variety. Under normal water condition, the highest Fe content and distribution ratio were in the stem of 'Cangmai-6001', which was the same for the leaf for 'Hanmai-9'. The Fe content in stem and glume and Fe distribution ratio in leaf and glume were higher than in other organs of 'Jimai-22'. Under water deficit condition, Fe content was highest in grain for 'Cangmai-6001'and 'Hanmai-9', but it was highest in leaf for 'Jimai-22'. For all the investigated varieties, the highest Fe distribution was in grain. Water deficit increased with the distribution of Cu and Zn, accumulation of Zn, Na and Ca in grain, water use efficiency and yield for 'Cangmai-6001', and with WUE_yield for 'Jimai-22'. However, water deficit decreased with the accumulation of Mn in the grain of 'Cangmai-6001', Cu and Mn in grain of 'Hanmai-9', Cu and Fe accumulation in 'Jimai-22' grain, water use efficiency, yield and dry matter weight of 'Hanmai-9'. Above all, 'Cangmai-6001' was more beneficial in terms of yield increase with higher WUE, higher Fe accumulation in grain and supplemented Mn element under water deficit condition. 'Jimai-22' had stable yield with increasing WUE and supplemented Fe element in grain under water deficit condition. For 'Hanmai-9' variety, the yield, WUE, Cu and Mn accumulation in grain decreased obviously under water deficit condition. Correlation analysis indicated that Cu, Zn, Ca and Mn had significant interaction with dry matter, with no direct effect on yield and WUE. This was related with the differences in variety and interaction effects of variety and water. There was still the tendency for mineral elements to regulate water utilization by influencing wheat dry matter formation, which needed further research and verification.