Using the seeds of 'Dongsheng' cabbage as material,we investigated seed germination characteristics, changes in relative electric conductivity,MDA content,soluble protein and soluble sugar contents and antioxidant related indexes during artificial aging at 40℃ and RH 100%. The results showed(1) :The seed moisture content and abnormal seedling rate after germination increased considerably with the increase of aging time, but the seed germination rate, germination potential, germination index and vigor index decreased; (2) The relative electrolyte leakage and soluble sugar content increased and soluble protein content decreased;The contents of malondialdehyde (MDA) firstly went up and then went down; (3) With the increase of the aging time, SOD, POD and CAT activities decreased significantly. The ascorbate peroxidase (APX) activities increased considerably after 2 d aging,and decreased after 6 d aging. In conclusion,during artificial aging treatment,the seed vitality and the germination rate decreased significantly,and the relative electrolyte leakage,soluble protein content and soluble sugar content is positively correlative with seed vigor index. The increased peroxidation of membrance lipids may also be the main mechanism for deterioration of 'Dongsheng' cabbage seeds during artificial aging.%以结球甘蓝品种‘冬升’种子为材料,研究高温(40℃)高湿(相对湿度100％)人工老化处理过程中种子的萌发特性、种子浸出液相对电导率和丙二醛、可溶性蛋白、可溶性糖含量以及抗氧化酶活性的变化,以揭示种子劣变的机理.结果表明:(1)人工老化处理甘蓝种子的含水量和不正常苗率均随着老化时间的延长逐渐增加,而种子发芽势、发芽率、发芽指数和活力指数的增加均逐渐降低.(2)随着处理天数的延长,老化处理甘蓝种子的浸出液电导率显著增大,浸出液可溶性糖含量逐渐升高,可溶性蛋白含量表现出显著下降趋势,而种子MDA含量呈先升高后逐渐下降的趋势.(3)在结球甘蓝种子老化进程中,其种子中SOD、POD、CAT活性变化的趋势相似,均随老化程度的加深而逐渐降低；而APX活性在老化处理的最初2d显著增加,第6天显著降低.研究发现,在结球甘蓝种子老化进程中,种子活力和萌发率显著降低,其种子浸出液电导率、可溶性蛋白含量、可溶性糖含量、保护酶活性变化与种子老化及劣变程度密切相关,膜脂过氧化作用可能是引起或加剧种子老化劣变的重要原因之一.
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