灌水量对膜下滴灌马铃薯生长、产量及水分利用的影响

Effects of irrigation quantity on growth,yield and water use efficiency of potato under mulched drip irrigation

为探索灌水量对膜下滴灌马铃薯生长、产量及水分利用的影响,在苗前、苗期、现蕾期、初花期、盛花期、落花期6个时期进行0(CK)、100、150、200、250、300、350、400 m^(3)·hm^(-2)灌水量处理研究。结果表明,不同灌水量均可缩短马铃薯现蕾前生育期而延长生育后期,也可提高花期叶面积指数。灌水量对现蕾前茎叶鲜、干质量影响较小,在现蕾期、初花期、落花期,茎叶鲜质量随灌水量的增加呈上升趋势,茎叶干质量在灌水量增至300 m^(3)·hm^(-2)时于成熟期降低。每hm2产量及单株产量、大中薯数量、质量均随灌水量的增加呈先上升后下降的趋势,每hm2产量在250 m^(3)·hm^(-2)灌水量时出现峰值,单株产量、大中薯数量及质量均在300 m^(3)·hm^(-2)灌水量时出现峰值,其最大值分别达78888.63 kg·hm^(-2)、1832.57 g、4.53粒、1720.47 g,产量较CK增产27712.26 kg·hm^(-2),增产率54.15%。当灌水量增至350 m^(3)·hm^(-2)及更大量时,植株在生育中后期出现徒长现象,茎粗变细,小薯增多,商品率、产量及水分利用率均显著下降。综合分析,250~300 m^(3)·hm^(-2)灌水量为半干旱区定西市马铃薯膜下滴灌较适宜水平。

In order to explore the effect of irrigation amount on the growth,yield and water use of potato under mulched drip irrigation,0(CK),100,150,200,250,300,350,400 m^(3)·hm^(-2) irrigation treatments were carried out at six stages of pre-seedling,seedling,squaring,early flowering,full flowering and falling flowering.The results showed that different irrigation amount could shorten the growth period of potato before budding and prolong the late growth period,and also increase the LAI at flowering stage.The irrigation amount had little effect on the fresh and dry mass of stems and leaves before budding.During budding,early flowering and falling,the fresh mass of stems and leaves increased with the increase of irrigation amount,and the dry mass of stems and leaves decreased at maturity when the irrigation amount increased to 300 m^(3)·hm^(-2).The yield per hm2 and yield per plant,the number and mass of large and medium-sized potatoes increased and then decreased with the increase of irrigation amount.The peak values appeared at 250 m^(3)·hm^(-2) and 300 m^(3)·hm^(-2) irrigation amount,respectively.The maximum values were 78888.63 kg·hm^(-2),1832.57 g·plant-1,4.53 g·plant-1 and 1720.47 g·plant-1,respectively.The yield increased by 27712.26 kg·hm^(-2) compared with CK,with an increase rate of 54.15%.When the irrigation amount increased to 350 m^(3)·hm^(-2) and more,the plant appeared overgrowth in the middle and late growth period,the stem diameter became thinner,the number of small potatoes increased,and the commodity rate,yield and water use efficiency decreased significantly.Comprehensive analysis showed that 250-300 m^(3)·hm^(-2) irrigation is the most suitable level for potato drip irrigation under film in semi-arid Dingxi city.