Effect of cultivation patterns on growth of maize root and water use efficiency

Field experiments were conducted in 2008~2009 to study the effects of 7 cultivation patterns on the distributions of maize roots, yield and water use efficiency (WUE). The objective of the study was to further make clear the enhancing mechanisms of maize production under full film mulching and double furrow system in northwest China and to lay the theoretical and technological basis of cultivation techniques for high-yield maize in arid/semi-arid areas. The results showed that while root length and dry weight gradually increased with growth duration, and they gradually declined with soil depth under different cultivation patterns. Root length in the 0~150 cm soil layer under even row-spacing sowing in furrow with whole film mulching was significantly longer than those under sowing in furrow with semi-film mulching and conventional cultivation with or without film mulching. Pinch sowing in furrow with whole film mulching had the highest percent root length distribution in the 120~150 cm soil depth, followed by even row-spacing sowing in furrow with whole film mulching. Conventional cultivation without film mulching had the least percent root length distribution in the 120~150 cm soil layer. Most of the root dry weight was concentrated in the 0~30 cm soil layer, and was higher in furrows than in ridges. Root dry weight order was as follows: sowing in furrow with whole film mulching > conventional cultivation with film mulching > sowing in furrow with semi-film mulching, even row-spacing sowing > pinch sowing. The results further showed that even row-spacing sowing in furrow with whole film mulching improved grain yield by 17.72%, 22.01% and 47.00%, and ,WUE by 6.41%, 18.54% and 43.57%, respectively, compared with sowing in furrow with semi-film mulching, conventional cultivation with film mulching and conventional cultivation without film mulching. Even row-spacing sowing in furrow with whole film mulching was the optimum maize cultivation method in Longdong area of northwest China.