Yield Performance and Resource Efficiency of Double-Cropping Maize in Yellow-Huai-Hai River Valleys Region

The winter wheat (Triticum aestivum L.)-summer maize (Zea mays L.) relay system (W-M system) is the main cropping pattern in the Yellow-Huai-Hai River Valleys region of China. In recent years, winter freezing and drought stress occur frequently in this area, which causes great loss of wheat yield. In this study, the double-cropping maize system (M-M system) was tested in Xinxiang, Henan Province in 2009 and 2010 growing seasons to compare grain yield and resource efficiency between M-M and W-M systems. Compared to the W-M system, the M-M system produced 2.3% higher annual yield and increased 26.1% annual light energy efficiency and 6.5% annual temperature production efficiency. Besides, the economic benefit in the M-M system was 1628 RMB ha⁻¹ higher than that in the W-M system, and the total growth duration was reduced 140 d in the M-M system. This result suggests that the M-M system not only facilitates land fallow and avoids winter freezing and drought stress, but also obtains high light and temperature efficiencies and economic benefit.