达草灭对橙色大白菜愈伤组织中类胡萝卜素含量的影响

Effects of Norflurazon on Carotenoid Content in Orange-heading Chinese Cabbage(Brassica campestris L.ssp.pekinensis) Calli

依据橙色大白菜的愈伤组织呈现橙色,而普通大白菜的愈伤组织呈现浅黄色这一现象,以橙色大白菜‘金冠1号’和普通大白菜‘秦白2号’培养的愈伤组织为材料,在培养基中添加0.1mmol·L-1的八氢番茄红素脱氢酶抑制剂达草灭分别处理5、10、20和40d。用HPLC法测定处理后的愈伤组织中各种类胡萝卜素含量的结果表明:‘秦白2号’愈伤组织中以β-胡萝卜素为主,‘金冠1号’愈伤组织中的类胡萝卜以番茄红素和β-胡萝卜素为主,且类胡萝卜素总含量比‘秦白2号’高出10.4倍;随着达草灭处理时间的延长,愈伤组织的颜色逐渐变白,其中番茄红素和β-胡萝卜素的含量逐渐下降,而八氢番茄红素的含量则逐渐升高,至处理40d时,两品种的愈伤组织中积累的八氢番茄红素差异不明显。据此,推论橙色大白菜中类胡萝卜素的积累并不是由于类胡萝卜素生物合成能力的提高引起的。

According to the phenomenon that the calli derived from ＇Qinbai 2＇ seedlings showed a light yellow color and the calli derived from ＇Jinguan 1＇ exhibited orange yellow, the calli from ＇Qinbai 2＇ and ＇Jinguan 1＇ were treated for 5 d, 10 d, 20 d and 40 d with 0.1 mmol.L1 norflurazon, an effective inhibitor of phytoene desaturase. The carotenoid content of treated calli were measured by High Pressure Liquid Chomatography （HPLC）. The results showed that β-carotene was the main component of carotenoid in the calli derived from ＇Qinbai 2＇, lycopene and β-carotene were the main components of carotenoid in the calli derived from ＇Jinguan 1＇. The total carotenoid content in ＇Jinguan 1＇ was 10.4 times more than that in ＇Qinbai 2＇. With the treatment of norflurazon, the growing calli became white and the contents of lycopene and β-carotene were decreased but phytoene content increased. After the treatment of norflurazon for 40 d, there was no obvious difference of phytoene accumulation between the ＇Qinbai 2＇ and ＇Jinguan 1＇ calli. These results suggested that carotenoid accumulation in the orange-heading Chinese cabbage didn＇t result from an increased capacity of carotenoid biosynthesis.