Difference of Water Consumption Characteristics and Grain Yield of Different Wheat Cultivars under High Yield Condition

To determine the reasonable and effective water saving irrigation scheme in wheat production,water consumption characteristics,grain yield and water use efficiency(WUE) were studied with two commercial wheat cultivars Shannong 15 and Yannong 21.The results showed that the amplitude of the relative error between the designed water content and the actual relative water content was 0.11%~4.71% in all treatments,which indicated that irrigation amount according to irrigation quota calculation formula could reach the designed water content.The treatment W1,which the relative water content at jointing stage and anthesis stage were 75% and 65%,respectively,had the highest irrigation efficiency for two wheat cultivars.The treatment W2,which the relative water content at jointing stage and anthesis stage were both 75%,obtained the highest grain yield and WUE.The grain yield and WUE of Shannong 15 was significantly higher than those of Yannong 21 under conditions of the treatment W1 and W2.The water consumption amount and soil water consumption amount of Shannong 15 were significantly higher than those of Yannong 21 in all treatments.The ratio of soil water consumption amount to water consumption amount of Shannong 15 was significantly higher than that of Yannong 21,but its ratio of precipitation to water consumption amount was significantly lower than that of Yannong 21,and the two wheat cultivars had no significant difference on the ratio of irrigation amount to water consumption amount under the conditions of treatment W0 and W1.There was no difference between Shannong 15 and Yannong 21 on the ratio of soil water consumption amount to water consumption amount and the ratio of precipitation to water consumption amount under the condition of treatment W2,but the ratio of irrigation amount to water consumption amount of Shannong 15 was significantly lower than that of Yannong 21.The soil water consumption amount in 20~60 and 60~100 and 140~200 cm soil layers of Shannong 15 was significantly higher than that of Yannong 21 under the conditions of treatment W0 and W1,which indicated that Shangnong 15 had higher ability of using soil water in deeper soil layers than Yannong 21.As far as grain yield and water use efficiency were concerned in the experiment,Shannong 15 was a high grain yield and high WUE wheat cultivar,and the most appropriate treatment for two wheat cultivars was the treatment W2 which the relative water content at jointing stage and anthesis stage were both 75%.