氮肥用量对蔬菜产量和品质的影响

采用田间微区池栽氮单因素多水平试验设计，研究了氮肥用量对油菜、生菜和茼蒿产量和品质的影响。结果表明，施用氮肥使３种蔬菜的产量分别增加５．４％－２５．９％、８．９％－２８．８％和８．８％－２１．７％，获得最高产量的施氮量分别是２７０kg/hm^2、１８０kg/hm^2和９０kg/hm^2，施氮量与蔬菜品质密切相关，在本试验条件下，油菜和生菜体内硝酸盐含量与施氮量呈显著正相关关系（Ｒ＊＝０．９５－０．９７）；茼蒿施氮比不施氮硝酸盐增加２０．９％，不同施氮量之间无显著差异。３种蔬菜外观品质和营养品质最佳的施氮量分别是１８０kg/hm^2、１８０kg/hm^2和９０kg/hm^2.表２，参５。

The Effect of NApplication rate on Yield and Quality of Vegetable

The effect of N application rate on yields and qualities of rape,lettuce and crowndaisy chrysanthemum was studied in protected soil.The results showed that application of certain amounts of N fertilizer increased the yields of these vegetables from 5.4% to 28.9%,but high N rates inhibited their growth.The nitrate,soluble sugar and total acidity contents in vegetables increased when the N application rate increase,and the Vc contents in vegetables reduced,and significant positive correlation were found between the N rates and nitrate contents (R＝0.95～0.97).