Impacts of planting systems on soil moisture, soil temperature and corn yield in rainfed area of Northeast China

The effects of different planting systems on soil conditions and crop growth are not well documented in cool high-latitude rainfed regions. Therefore, a field experiment was conducted from 2009 to 2011 to evaluate the impacts of planting systems on soil moisture, soil temperature and corn yield in the center of Northeast China. The experimental design was randomized complete block with three replications. Three planting systems (RP: ridge planting, FRP: flat planting with ridging at early jointing stage, and FP: flat planting without ridging) were tested in this study. Corn yield was significantly higher under FRP than under RP and FP by 302.2 and 552.3 kg ha−1, respectively, on average across the three experimental years (P < 0.05). Significant differences in soil moisture were found in the early stage of the growing season. Soil water storages in 0-40 cm depth under FRP and FP were higher than under RP during the period from sowing to seedling stages (VE to V1 stages). Meanwhile, significant differences in topsoil temperatures occurred among planting systems during early growth period. The FRP and FP significantly increased the daily minimum temperature in the soil layer of 5 cm on average by 1.2 and 1.1 °C compared to RP during the period from VE to V1 stage, despite the fact that the daily maximum temperatures were correspondingly 2.4 and 2.6 °C lower, respectively. Compared to FP, RP and FRP could reduce waterlogging by draining extra rainwater through furrows during the later growth period. The above findings indicate that FRP can benefit corn cropping for higher yield through mitigating soil temperature and moisture limitations to corn growth in cool high-latitude rainfed areas.