氮素水平对芥蓝生长及芥子油苷含量的影响

Effect of nitrogen level on growth and glucosinolates content of Chinese kale

采用溶液培养方法,研究了不同供氮水平对芥蓝生物量及抗癌次生代谢物芥子油苷含量的影响。结果表明,氮素水平从N100 mg/L到常规营养液的N200 mg/L范围内,芥蓝地上部、根部及菜苔鲜重均随供N水平的提高而显著增加,但菜苔总芥子油苷含量却随供N水平提高而显著降低;当N素水平提高到N300～400 mg/L时,芥蓝生物量不再显著增加;而菜苔总芥子油苷含量相对于N150和200 mg/L处理却显著增加。由于脂肪族和吲哚族芥子油苷分别来源于不同的氨基酸,两者的含量随供N水平的变化趋势不同。脂肪族芥子油苷含量以N100 mg/L处理最高,是常规供N(200 mg/L)处理的1.2倍,吲哚族芥子油苷以400 mg/L处理最高,是常规供N处理的1.5倍。显然,在常规营养液的供N水平下,可以获得理想的芥蓝生物产量;但适当提高供N水平,在保证高产的同时可显著提高芥蓝菜苔的芥子油苷含量,有利于提高其抗癌品质。

A hydroponic experiment was conducted to investigate the effect of different N levels on the growth and anticancer glucosinolates content of Chinese kale （ Brassica alboglabra ）. Results indicated that as N level increased from the lowest level of N 100 mg/L to the conventional level of N 200 mg/L, fresh weights of shoot, root and bolting stem increased, while the total glucosinolates content of bolting stem decreased significantly. When N level ranged between N 300 to 400 mg/L, the biomass of Chinese kale was not significantly increased compared with the conventional N level, while the total glucosinolates content was sharply increased contrasted to the two lower N levels of 150 and 200 mg/L, respectively. The different effects of N level on the contents of aliphatic and indolyl glucosinolate were found due to their different original amino acids. The highest content of aliphatic glucosinolates was observed at the N level of 100 mg/L, which was 20 percent higher than that under the conventional N level. While the highest content of indolyl glucosinolates was detected at the N level of 400 mg/L, which was 50 percent higher than that under the conventional N level. In conclusion, N level not only significantly affected the biomass of Chinese kale but also sharply influenced the content of glucosinolates. Although the conventional N level could supply Chinese kale enough nutrition to get high biomass product, relatively higher N level was expected to increase the content of anti-cancer glucosinolates.