摘要： 水培情况下，收获前12 d用甘氨酸、异亮氨酸和脯氨酸的不同组合及尿素替代营养液20%硝态氮，降低了不结球白菜与生菜叶片及叶柄硝酸盐含量，而对产量影响不大。以单一甘氨酸效果最好，甘氨酸、异亮氨酸和脯氨酸三者混合次之，生菜以1次替代，而不结球白菜2次为宜，处理3 d后收获；叶片全氮含量显著增加。不结球白菜对尿素的吸收利用效率大于生菜，同化能力强，尿素对体内硝酸盐含量的降低效果与氨基酸无显著差异，而氨基酸对生菜作用大于尿素。

关键词: 不结球白菜, 生菜, 氨基酸, 尿素, 硝酸盐

Abstract: Under liquidculture conditions,different mixture of glycine(Gly),isoleucine(Iso)and proline(Pro)and urea used as partial(20 %)replacement of nitrate in solution reduced content of nitrate of nonheading Chinese cabbage(Brassica campestris ssp.chinensis(L.)Makino cv.huawang)and lettuce(Lactuca sativa L.cv.boli)12 d before harvest,however,top yields were not affected.Gly had the best reducing results,while the mixture of Gly,Iso and Pro in the next place,the number of partial replacement times of nitrate by amino acid in lettuce and nonheading Chinese cabbage was 1 and 2,respectively,vegetables were harvested 3 d after treatment,total-N in leaves increased significantly(p<0.05).Capacity of assimilation of urea was higher in nonheading Chinese cabbage than in lettuce,The effects showed that reducing nitrate effects of amino acid and urea in nonheading Chinese cabbage were almost the same,but using amino acid was more effective than using urea in lettuce,amino acid has much more effective than urea in lettuce.

Key words: Nonheading Chinese cabbage, Lettuce, Amino acid, Urea, Nitrate

中图分类号: 

• S143.1