减量施肥对三种蔬菜硝酸盐含量、营养品质和生理特性的影响

Effects of Fertilizing Decreasing on Nitrate Contents,Nutritional Quality and Biological Characteristics of Three Vegetables

在大棚种植条件下,以小青菜、杭白菜和苋菜3种蔬菜为试验材料,分别设置了3个不同的施肥处理:常规施肥(75.00 kg/hm2)、减量25%(56.25 kg/hm2)和减量35%(48.75 kg/hm2)。研究了施肥水平对这3种蔬菜的硝酸盐积累量、产量、营养品质和生理特性的影响。结果表明:(1)减量施肥能有效降低蔬菜体内的硝酸盐含量,但对产量无显著影响。(2)减量施肥对此3种蔬菜的营养品质指标VC含量、蛋白质含量和可溶性糖含量均无显著影响。(3)减量施肥使蔬菜CAT酶活性上升,POD和SOD酶活性下降,可能导致H2O2减少,羟自由基减少,进而引起叶片脂膜过氧化减轻,MDA含量降低;同时使NR酶呈上升趋势,其活性与施肥量呈显著负相关。因此,在土壤肥力适度的条件下,适当减少施肥量既能降低蔬菜中硝酸盐的含量且能保持产量,保证营养。

Take Greengrocery,Chinese Cabbage and three-coloured amaranth as test materials,fertilizer supply treatments with 75.00 kg/hm2,56.25 kg/hm2 and 48.75 kg/hm2,studying on the effects of different fertilizing levels on nitrate content,nutritional quality and biological characteristics of three vegetables.The results shows that：（1）The nitrate content were reduced effectively with the fertilizer supply decreasing,but had no significant influence to biomass of the vegetables.（2） VC,protein and soluble sugar content did not change significantly with the fertilizer supply decrease.（3） Fertilizer supply decrease caused CAT activity increased,POD and SOD activity decreased,leading to membrane lipid peroxidation decreased,then MDA content decreased,meanwhile NR activity increased,which was correlated with fertilizer supply.So fertilizer supply decrease can reduce nitrate content in vegetables but keep biomass and nutritional quality.