中文摘要：

采用溶液培养方法研究了43种基因型小白菜在不同硝铵比条件下体内硝酸盐含量的变化情况。结果表明,不同基因型小白菜的硝酸盐含量差异较大,东妃青梗菜、上海白叶四月蔓和夏优高抗为低硝酸盐含量基因型小白菜,而高雄甜脆小白菜、宝大矮棋青和苏州青为高硝酸盐含量基因型小白菜。硝铵比50/50是最适宜筛选的氮素形态比例,而叶片中的硝酸盐含量也是最适宜的筛选指标。对上述6个基因型小白菜进一步分析结果表明,不同部位硝酸还原酶、根系硝态氮最大吸收速率以及亲和力这三个因素对小白菜各部位的硝酸盐积累都有显著的影响,但在不同部位,这三个因素所起的贡献率不同。

英文摘要：

Hydroponic experiments were carried out to study the nitrate accumulation of 43 Chinese cabbage genotypes under the nutrient solution of different NO3^-/NH4^＋ ratio.The results indicated that the discrepancies in nitrate contents among different genotypes were significant,and accordingly,Dongfei,Shanghai baiye and Xiayou gaokang as the low nitrate concentration genotypes,and Gaoxiong tiancui,Baoda aiqi,Suzhouqing as the high nitrate concentration genotypes were screened out.Here,the nitrogen source of NO3^-/NH4^＋ 50/50 and the nitrate content in leaves can be considered as the best nutrient solution and index for nitrate accumulation screening.Further study on these six genotypes of Chinese cabbage suggested that the effects of nitrate reductase,maximum nitrate uptake and affinity on nitrate accumulation were significant,while showed different contribution in different part of plants.