Abstract:

In order to explore the effects of different irrigation methods on alfalfa(Medicago sativa)growth, water use efficiency and yield, a field experiment was carried out to study the change of alfalfa growth under four different irrigation treatments, including subsurface drip irrigation (SDI), border irrigation (BI), sprinkler irrigation (SI) and control treatment (CK, no irrigation). Results showed that different irrigation methods had different effects on soil water content, and SDI treatment had the highest soil water content during the experimental stage. Plant height, primary shoot number, leaf area of each plant and weight of each plant of SDI treatment increased significantly compared with those of BI,SI and CK treatments (P < 0.05). In addition, this study presented that different irrigation treatments had different effects on alfalfa yield and water use efficiency. Yield of the second cutting and the third cutting alfalfa of SDI treatment ware 4815.87and 4300.41 kg·hm^-2,^rrespectively. Compared with BI, SI and CK treatments, yield of the second cutting alfalfa of SDI increased by 10.56%, 14.92% and 95.26%, and the third cutting by 13.64%, 23.60% and 120.85%, respectively (P < 0.05). Water use efficiency of the second cutting and the third cutting alfalfa of SDI treatment ware 2.66 and 2.50 kg·m^-3, respectively. Compared with BI and SI treatments, water use efficiency of the second cutting of SDI increased by 17.70% and 21.46%, and the third cutting by 20.77% and 34.41%, respectively (P < 0.05). Therefore, considering growth, yield and water use efficiency of alfalfa, the subsurface drip irrigation was the most suitable irrigation method in arid northwest China.

Key words: Alfalfa, Subsurface drip irrigation, Sprinkler irrigation, Border irrigation, Yield, Water use efficiency

摘要：

为探讨不同灌溉方式对紫花苜蓿(Medicago sativa)生长、水分利用效率及产量的影响,通过田间试验研究了地下滴灌(SDI)、畦灌(BI)、喷灌(SI)和不灌溉处理(CK)4种灌溉方式下苜蓿生长的变化。结果表明:各处理间,SDI的土壤含水率在试验期间最高,且SDI的苜蓿株高、分枝数、单株叶面积及单株干重均显著高于BI,SI和CK;SDI两茬的产量分别为4815.87和4300.41kg·hm^-2,与BI,SI和CK相比,第2茬分别提高了10.56%,14.92%和95.26%,第3茬分别提高了13.64%,23.60%和120.85%,均达到显著水平(P<0.05);SDI两茬的水分利用效率分别为2.66和2.50kg·m^-3,较BI和SI处理,第2茬分别提高了17.70%和21.46%,第3茬提高了20.77%和34.41%,均达到显著水平(P<0.05)。因此,从苜蓿生长、产量及水分利用效率角度考虑,地下滴灌是西北旱区最为适宜的灌溉方式。

关键词: 紫花苜蓿, 地下滴灌, 畦灌, 喷灌, 产量, 水分利用效率