Genotype difference of soil water dynamics and yield of winter wheat under different water supply conditions

LSD is adopted to analyze quantitatively the yield and its constituents and ecological indexes of winter wheat under different water supply conditions which included four irrigation treatments such as no irrigation,1 irrigaiton,2 irrigation and 3 irrigation in North China Plain,and study is also made on soil water dynamics at the same time to probe into genotype differences of different winter wheat with Kemai yi and Shijiazhuang 8.It concludes that the soil water of 0～140 cm depth of all irrigation treatments changes greatly,while 0～40 cm and 80～140 cm depth of no irrigation treatment changes actively,but the change extent is lower than the former.The change tendency of soil water with the same treatment between different varieties is nearly consistent.Except 1 irrigation treatment,the extent of change of Shijiazhang 8 of other three treatments is greater than that of Kemai yi.The yields of Kemai yi and Shijiazhuang 8 of 3 irrigation treatments are highest,increased by 44.44% and 42.88% respectively compared with that of no irrigation.However,the wheat of 3 irrigation treatments matures late as a result of sufficient irrigation and great water consumption,leading to a sharp decrease of soil water before harvest.The yield constituents were significantly different among all the treatments. The spike number of 3 irrigation treatment was the highest,while the grain weight per spike of 1 irrigation treatment was the highest because of insignificant difference between 1 and 2 irrigation treatments,the 1000-grain weight of no irrigation was the highest,and the grain number per spike of 1 irrigation was the highest.The harvest index of no irrigation was significantly different from irrigation treatments.The result further indicated that Kemai yi is more sensitive but with less water consumption than Shijiazhang 8.The optimal irrigation schedule is that Kemai yi is irrigated 2 times scientifically and Shijiazhang 8 is irrigated 3 times.