补灌水平对宁南山区露地青花菜产量、品质及耕层水分动态的影响

为探究宁夏南部山区自然降水条件下露地青花菜的最佳补灌灌溉方案,采用大田田间对比试验,设置5个补灌水平,在宁夏原州区冷凉蔬菜基地开展补灌水平对土壤水分分布、青花菜产量、品质、水分利用效率的试验研究。结果表明,青花菜全生育期自然降雨主要集中在7月份,且占全生育期降雨量的78.49%,此月份无需补灌即可满足生育后期对水分的需求;不同处理青花菜生育期内土层深度20 cm处土壤含水率总体表现为W5(27mm·667m^-2)>W4(22.5mm·667 m^-2)>W3(18 mm·667 m^-2)>W2(13.5 mm·667 m^-2)>W1(9 mm·667 m^-2),补灌后各处理土壤含水率均达到田间持水量的85%以上;补灌灌溉水平对青花菜花球产量性状、营养品质均有显著影响,W3处理经济总产量最高,达1524.10 kg·667 m^-2,显著高于其他处理6.28%~33.24%;可溶性糖和可溶性蛋白含量也最高,W3可溶性糖含量显著高于W1、W4和W5处理24.46%、12.20%、21.41%,W3可溶性蛋白含量显著高于W135.78%,且可溶性固形物和维生素C质量分数也较高,分别为6.26 g·100 g^-1和9.57 mg·100 g^-1。基于主成分分析的青花菜膜下滴灌最优补灌方案为补灌灌溉定额为69 mm,苗期-莲座期补灌灌水2次,灌水量为33mm,莲座期-球前期补灌灌水2次,灌水量36mm,结球前期-采收期补水主要依靠自然降雨。该结果可为本区露地冷凉青花菜夏季栽培产量的积累与水资源的合理应用提供理论指导。

Effect of supplementary irrigation level on yield and quality of broccoli and water dynamics in cultivated layer in Ningxia southern mountainous area

To explore the optimal supplementary irrigation scheme of broccoli in open field under natural precipitation conditions in the mountainous area of southern Ningxia,field comparative experiment was carried out,and 5 supplementary irrigation levels were set,the effect of supplementary irrigation level on soil moisture distribution,the yield,quality and water use efficiency of broccoli was investigated at the cold vegetable base in Yuanzhou District of Ningxia.The results showed that the natural rainfall during the whole growth period of broccoli was mainly concentrated in July,accounting for 78.49%of the total rainfall during the whole growth period.In this month,no supplementary irrigation was needed to meet the water demand of broccoli at the late growth stage.The soil moisture contents at 20 cm soil depth in the growth period of broccoli under different treatments were generallyW5>W4>W3>W2>W1.After supplementary irrigation,the soil moisture contents of each treatment reached more than 85%of the field capacity.The the yield traits and nutritional quality of broccoli were significantly affected by the supplementary irrigation level.The yield ofW3 treatment was up to 1524.10 kg per 667 m2,which was significantly higher than those of other treatments(6.28%-33.24%).The soluble sugar and soluble protein of W3 treatment were the highest,the soluble sugar of W3 was significantly higher than those of W1,W4 and W5(24.46%,12.20%,21.41%respectively),and soluble protein of W3 was significantly higher than W1(35.78%).The contents of soluble solids and Vitamin C were also high,which were 6.26 mg·100g^-1 and 9.57 mg·100 g^-1,respectively.Based on principal component analysis,the optimal supplementary irrigation scheme of broccoli drip irrigation under mulch was W3,the supplementary irrigation amount was 69 mm,the supplementary irrigation was carried out twice from seedling stage to rosette stage,with an irrigation amount of 33 mm,the supplementary irrigation was carried out twice from rosette stage to early stage,with an irrigation amount of 36 mm,the supplementary irrigation mainly depended on natural rainfall during early heading stage to harvest stage.The results can provide theoretical guidance for the accumulation of broccoli yield in summer and the rational application of water resources in the mountainous area of southern Ningxia.