Yield-increase effect of film-mulching and planting pattern on dryland spring maize

Film mulching is the main mode of cultivation of spring maize in drylands. However, few studies have been conducted on the water use, root development and anti-collapse mechanisms of dry spring maize under different mulching conditions. A field research was carried out in 2013-2015 at Qianying Experimental Station of Cangzhou Academy of Agriculture and Forestry Sciences. Spring maize (Zhengdan 958) was grown for 3 years under five film-mulching and planting patterns, which were flat planting without film mulching (CK), flat film mulching and sowing under film (FC-SUF), flat film mulching and film skirting sowing (FC-FSS), film mulching on ridge and sowing under film (RC-SUF), and film mulching on ridge and film skirting sowing (RC-FSS). Yield, yield components, soil moisture, roots and lodging resistance of spring maize were investigated at different growth stages. The results showed that yields of maize under RC-FSS, RC-SUF, FC-FSS and FC-SUF increased respectively by 24.97%, 17.75%, 11.69% and 17.75% over that of CK, with RC-FSS having the highest yield. Water use efficiency (WUE) under RC-FSS increased by 26.27% compared to CK. In the 0-20 cm soil layer, soil water content was increased by 30.44%-47.66% (P < 0.01) under RC-FSS compared with CK. Spring maize under RC-FSS had the maximum lodging resistance (29.4 N), which was significantly higher than that of CK (P < 0.05). Film mulching increased soil temperature in the 0-10 cm soil layer to 0.3-2.3℃, and RC-SUF had the maximum soil temperature. RC-FSS had greater root diameter and dry weight of spring maize than RC-SUF, FC-SUF and CK (P < 0.05). This study indicated that film mulching on ridge and film skirting sowing increased or maintained yield of spring maize by increasing rainwater storage and soil moisture conservation, root growth promotion and lodging resistance. It implied that it was possible to extensively apply film mulching in the coastal plain areas with drought and little rainfall in spring.