不同形态氮素替代部分硝态氮对水培小白菜的生长和品质的影响

摘 要：为了研究水培生产上营养液中氮素形态对小白菜产量和品质的影响，本实验以华南农业大学叶菜B配方为基础, 研究了水培条件下不同形态氮素（铵态氮、酰胺态氮、氨基酸态氮）替代部分硝态氮对水培小白菜的生长和品质的影响。结果表明，氨基酸态氮和酰胺态氮部分替代硝态氮可以显著促进小白菜的生长，提高小白菜的产量；铵态氮部分替代硝态氮利于小白菜叶绿素和类胡萝卜素含量的增加；氮素为纯硝态氮时，小白菜的根系活力最高，酰胺态氮的替代部分硝态氮后，小白菜根系活力显著下降，但可溶性糖、可溶性蛋白和维生素C的含量显著提高；不同形态的氮素替代部分硝态氮后，降低了小白菜体内硝酸盐的含量，尤以酰胺态氮替代后降幅较大。综合小白菜收获时的产量品质等因素，酰胺态氮替代部分硝态氮对水培小白菜的栽培效果最好。

Effects of Partial Replacement of Nitrate in Solution by Nitrogen Forms on the Development and Quality of Hydroponic Pakchoi Cabbage.

In order to study the effects of the nitrogen forms in nutrient solution on the pakchoi cabbage,the effects of partial replacement of nitrate in solution by nitrogen forms （ammonium nitrogen;amide nitrogen;amino acid nitrogen） on the development and quality of hydroponic pakchoi cabbage were studied based on the South China Agricultural University nutrient solution formula B for leaf vegetables.The results showed that the growth and the yield of hydroponic pakchoi cabbage were increased remarkably,when the partial nitrate in solution were replaced by amino acid nitrogen and amide nitrogen.The chlorophyll and carotenoid content of the hydroponic pakchoi cabbage were raised,when the partial nitrate in solution were replaced by ammonium nitrogen.The root vigor of the of the hydroponic pakchoi cabbage was the highest,when the nitrogen in solution were all nitrate;the root vigor was lowered,but the soluble sugar,soluble protein and Vitamin C content of the hydroponic pakchoi cabbage were raised when the partial nitrate in solution were replaced by amide nitrogen.The nitrate content of the hydroponic pakchoi cabbage was lowered remarkably when the part of nitrate was replaced by other nitrogen forms,especially by amide nitrogen.In this experiment,the cultivation effect of the hydroponic pakchoi cabbage was the best when the partial nitrate in solution was replaced by amide nitrogen.