[Effects of stubble-standing mode on the grain yield and water use efficiency of wheat and maize in wheat/maize intercropping system].

Wheat/maize intercropping is the main intercropping pattern in the irrigation region of Hexi Oasis, Northwest China, but the traditional intercropping needs much water, making the regional water resource lacked increasingly. In 2010, a field experiment was conducted in the irrigation region of Shiyang River basin oasis, Gansu Province of Northwest China, aimed to study the effects of traditional stubble-burning, stubble-returning, and stubble-standing on the grain yield, water use efficiency (WUE), and economical benefits of wheat and maize in wheat/maize inter-cropping system. Compared with stubble-burning and stubble-returning, stubble-standing increased the grain yield of mono- and intercropped wheat by 7.2% and 5.1% , and 6.2%, 5.1%, and that of mono- and intercropped maize by 4.7% and 2.5%, and 7.2% and 3.3%, and increased the WUE of mono- and intercropped wheat by 20.4% and 16.2%, and 17.9% and 14.6%, and that of mono- and intercropping maize by 16.7% and 10.9%, and 11. 8% and 17.0%, respectively. As for the mono- and intercropped wheat and maize, their average net economical benefits under stubble-burning, stubble- returning, and stubble-standing were 10946, 11471, and 13454 RMB.hm-2, respectively. In considering the grain yield, WUE, and economic benefits, stubble- standing would be the optimal mode of wheat/maize intercropping in the oasis of Hexi irrigation region, Northwest China.