河西绿洲不同生育期调亏灌溉对马铃薯生长、产量及品质的影响

Effect of Regulated Deficit Irrigation at Different Growth Stages on Potato Growth,Yield and Quality in Hexi Oasis

在河西走廊张掖市甘州区党寨镇田家闸灌溉试验站开展了马铃薯不同生育期调亏灌溉的试验研究。在保持其他生育期土壤水分为正常灌溉(土壤含水率65%~75%)的情况下,在马铃薯的幼苗期、块茎形成期、块茎膨大期和淀粉积累期分别进行轻度(土壤含水率55%~65%)的调亏处理,以全生育期的正常灌溉作为对照,进行马铃薯生长指标、产量和水分利用的测定。试验结果表明,不同生育期水分调亏均引起马铃薯株高、茎粗和单株总生物量降低,其中块茎膨大期水分亏缺降低程度最为显著。调亏处理中,苗期轻度水分调亏处理马铃薯产量33 027.22 kg/hm^(2),与对照无显著差异,水分利用效率和灌溉水利用效率最高,分别达到6.91和9.38 kg/m^(3),而且能够显著提升马铃薯综合品质。而块茎形成期马铃薯产量和水分利用效率最低,仅分别为24 047.32 kg/hm^(2)和5.85 kg/m^(3),且造成马铃薯品质下降。膜下滴灌调亏可促进水分利用效率和灌溉水利用效率提高,且苗期轻度水分调亏对马铃薯稳定提质和改善当地水分利用现状有积极意义。

Experimental study of regulated deficit irrigation at different growth stages was carried out in Tianjiazha irrigation experimental station of Zhangye City in Hexi Corridor.Under the condition of keeping soil moisture at other growth stages as normal irrigation(soil moisture threshold 65%~75%),in the seedling stage,tuber formation stage,tuber expansion stage and starch accumulation period of potato were treated with mild deficit(soil moisture threshold 55%~65%).Normal irrigation in the whole growth period was used as control,the physiological indexes,yield and water use of potato were determined.Test results showed that plant height,stem diameter and total biomass per plant decreased at different growth stages.Among them,the degree of water deficit was most significant in the tuber expansion period.Regulated deficit treatment,the yield of potato was 33027.22 kg/hm^(2) at a slight water deficit in seedling stage,but there was no significant difference between control and adequate water supply.Water use efficiency and irrigation water use efficiency were the highest,reached 6.91 and 9.38 kg/m^(3),and it could significantly improve overall quality of potato.Potato yield and water use efficiency were lowest in tuber formation stage,only 24047.32 kg/hm^(2) and 5.85 kg/m^(3),and the quality of potato decreased.Therefore,drip irrigation under plastic film mulch could improve water use efficiency and irrigation water use efficiency.In addition,slight water deficit in seedling stage had a positive effect on the stability of potato yield,improving quality and water use efficiency.