Effects of Increasing Temperature and Harvesting Rainwater Technique on Maize Yield and Water Use Efficiency in the Semi-Arid Region of China.

The acreage of maize has being increased in the north semi-arid region of China and there was risk for low temperature and drought. To quantify the effects of planting pattern with alternate ridges and furrows with plastic film mulching on soil temperature and moisture, crop growth and yield, and water use efficiency (WUE), the maize field experiment was conducted for three years from 2012 to 2014 in a semi-arid region in Wuchuan county, Inner Mongolia, China. In 2012 and 2013, the experiment included three treatments: flat plot without mulching (CK), alternating mulched row and bare row without ridge (MNR) and plastic film mulching on ridges (FMR). An additional treatment of full mulching on double ridges and furrows (DRFM) was tested in 2014. The mulching practices increased topsoil temperature by 3.2℃ and 2.5℃ for DRFM and MNR, advanced emergence by 3-5 days and increased grain filling by 9-12 days. By comparison with CK, mulching treatments increased water use efficiency (WUE) by 91%, 65% and 60% for DRFM, MNR and FMR in 2014, respectively. Of the three mulching practices, the full mulching treatment produced the greatest maize yield, which increased by 76% compared to flat plot without mulching. All mulching practices did not increase yield due to the serious frost in 2012. The FMR treatment increased the yield by 4% in 2013 and 42% in 2014 but the effects were not significant (P>0.05). However, the MNR treatment significantly increased grain yield by 9% in 2013 and 53% in 2014 (P<0.05). The differences of the beneficiary effects of mulching among years were primarily due to temperature stresses in 2012 and 2014. Nevertheless, mulching practices played a vital role in increasing maize productivity.