调亏滴灌对土壤水盐分布与河套蜜瓜产量的影响

Effect of regulated deficit irrigation on soil water-salt distribution and fruit yield of Hetao muskmelon under drip irrigation

研究不同生育期调亏及亏缺程度对土壤水盐分布和河套蜜瓜产量的影响。采用田间滴灌试验,分别在蜜瓜伸蔓期和结果期进行20%、30%和40%灌水量亏缺处理。试验结果表明：充分灌溉处理（T1）的土壤剖面含水率随时间波动最为剧烈,伸蔓期和结果期亏缺处理的土壤剖面含水率平均极差分别比T1低48.5%和80%。各处理的土壤剖面盐渍度随时间均有增长趋势,T1的土壤剖面平均电导率在生育期前后的增幅为0.026ds/m,亏缺灌溉处理的增幅为0.073~0.098ds/m。伸蔓期和结果期亏缺处理的产量平均值分别比充分灌溉处理显著降低16.0%和20.5%,但2个时期亏缺处理的产量之间不存在显著性差异。伸蔓期亏缺处理的平均灌溉水利用效率比T1低11.6%,而结果期亏缺处理比T1高6.5%。在结果期亏缺处理中,进行30%灌水量亏缺的T7产量最高,并与伸蔓期各亏缺处理相对于T1的减产幅度相差不大,但灌水量比T1低25.0%,灌溉水利用效率比T1高9.0%。因此,为取得较好的节水效应和灌溉水利用效率,T7是滴灌条件下河套蜜瓜覆膜起垄种植的最佳选择。

To investigate the effect of different growth period and deficit level of regulated deficit irrigation on the fruit yield of Hetao muskmelon,as well as the temporal and spatial distribution characteristics of the soil water and salt,a field drip irrigation experiment was conducted,imposing 20%,30%,40% deficit level in the vine stretching stage and fruit setting stage,respectively.The results showed that T1＇s fluctuation of soil moisture content over time was the most dramatic and the average range of deficit irrigation treatments in the vine stretching and fruit setting stage was lower than T1 by 48.5% and 80%,respectively.The trend of each treatment＇s soil profile salinity over time were growing,compared with the value before growth season,the growth range of salinity after growth season in T1 was0.026ds/m,while that in deficit irrigation treatments varied from 0.073ds/m to 0.098ds/m.The yield of deficit irrigation treatments in the vine stretching stage and fruit setting stage was lower than T1 by 16.0% and 20.5%,but there were no significant differences between the yields of deficit irrigation treatments in two growth stages.The average irrigation water use efficiency of deficit irrigation treatments in the vine stretching stage was lower than that of T1 by 11.6%,while that in fruit setting stage was higher than T1 by 6.5%.Yield of the deficit irrigation treatment which imposed 30% deficit level（T7）was the highest in three deficit irrigation treatments of fruit setting stage.When compared with T1,the yield reduction range between T7 and the deficit irrigation treatments in the vine stretching stage were similar,but T7＇s amount of irrigation was lower than T1 by 25.0%,as well as its irrigation water use efficiency was higher than T1 by 9.0%.Therefore,in order to achieve good water-saving effect and high irrigation water useefficiency,T7 was the best choice for plastic film mulching and ridging cultivated Hetao muskmelon under drip irrigation.