调亏灌溉对滴灌甜菜生长和产量的影响

为探讨滴灌条件下甜菜节水、高产、高效灌溉指标,于2016年在呼和浩特市开展了田间灌溉试验,研究了调亏灌溉对甜菜生长特性及产量和水分利用效率的影响。结果表明,叶丛快速生长期中度水分亏缺处理(50%θ_f~60%θ_f)在复水后叶面积、根部干物质量、净光合速率和蒸腾速率都有补偿效应,重度水分亏缺处理(40%θ_f~50%θ_f)对植株的生长有抑制作用;块根糖分增长期的调亏灌溉对甜菜生长和生理过程影响小于叶丛快速生长期的,中度水分亏缺处理(50%θ_f~60%θ_f)在复水后根部干物质量和光合作用都有补偿效应,重度水分亏缺处理(40%θ_f~50%θ_f复水后也能恢复生长。综合考虑甜菜块根产量和水分利用效率等指标,叶丛快速生长期和块根糖分增长期的适宜灌水量为1 147.78和635.54 m~3/hm~2。

Effects of Regulated Deficit Drip Irrigation on Growth and Yield of Sugar Beet

We present the results of a field experiment aimed to elucidate the effects of regulated deficit drip irri-gation on growth traits, yield and water use efficiency of sugar beet. The results showed that over the vegetative developmental period, a moderate water deficiency by keeping soil moisture content at 50%~60%of the field capacity had a compensatory effect on leaf area, dry root weight, net photosynthetic rate and transpiration rate af-ter re-wetting, whilea severe water deficiency with soil moisture being 40%~50%of the field capacity had an inhibitory effect on the growth of the plant. It was also found that a deficit irrigation during the root swelling pe-riod had less effects on growth and physiological development of the plant than that during the vegetative devel-opmental period. Considering the yield and water use efficiency, it was concluded that an irrigation amount of 1147.78 m3/hm2 over the vegetative development stage and another 635.54 m3/hm2 over the root swelling stage are optimal for deficit irrigation.