地下调亏滴灌对紫花苜蓿生长和产量的影响

Effects of Regulated Deficit Irrigation on Growth and Hay Yield of Alfalfa Under Subsurface Drip Irrigation

为提高苜蓿饲草产量和水分利用效率,研究了地下滴灌条件下调亏灌溉对紫花苜蓿株高、叶绿素、茎叶比和产量的影响。试验设置3个灌溉下限处理,田间持水量的70%为对照处理,设置田间持水量的50%和60%2个调亏灌溉处理。研究结果表明:随灌溉调亏程度加重苜蓿前2茬株高和草产量呈递减趋势,对第3茬影响不显著;调亏灌溉对苜蓿叶绿素SPAD值和茎叶比无显著影响;轻度调亏灌溉(田间持水量的60%)下苜蓿干草产量无显著降低。综合分析表明,地下滴灌轻度调亏灌溉(田间持水量的60%)下可实现紫花苜蓿丰产节水生产。

In order to increase the output and water use efficiency of alfalfa, the experiment was conducted to study the effects of regulated deficit irrigation(RDI) on plant heights, chlorophyll content, stem and leaf ratio and hay yield of alfalfa under subsurface drip irrigation. Three lower irrigation limit treatments are set in the experiment. 70% of the field water holding capacity is the control treatment, and two regulated deficit irrigation treatments are set at 50% and 60% of the field water holding capacity. The results show that the height and grass yield of the first two stubble of alfalfa decrease with the increase of irrigation deficit, but the effect on the third stubble is not significant;regulated deficit irrigation has no significant effect on the SPAD value and stem-leaf ratio of alfalfa;hay yield of alfalfa does not decrease significantly under light regulated deficit irrigation(60% of field water capacity).The comprehensive analysis shows that low regulated deficit irrigation with subsurface drip irrigation(60% of field water holding capacity) can achieve high yield and water saving production of alfalfa.