TrxS基因过表达对大麦种子抗老化能力的影响

摘要

The homologous transgenic barley line (Y002) of over-expressing Trxs and its nontransgenic parent (CK1) were used to study the effects of thioredoxin (Trx) on artificial ageing resisitance of bayley seeds.The results showed that:(1) In comparison with CK2 (non-ageing treatment),the artificial ageing treatment decreased significantly the germination vigor and germination percentage of barley seeds (P＜0.05),but the decreasing level of transgenic seeds was lower than that of non-transgenic seeds.After 3 days of treatment,the seed germination vigor and germination percentage of transgenic line Y002 were 20.00％ and 22.20 ％ higher than CK1 (P＜0.05),respectively.(2)The MDA,carbonyl content and relative conductivity all increased with the time of ageing treatment,but they were generally lower for transgenic line Y002.The MDA,carbonyl content and relative conductivity of Y002 seeds were 22.69％,15.02％ and 17.75％ lower than CK1 (P＜0.05) respectively,at the 3rd day after ageing treatment.(3) In the condition of artificial ageing treatment,the antioxidant enzyme activity of seeds was higher in Y002 than in CK1.The activity of CAT after 3-day treatment and the activity of POD after 2-day treatment for Y002 were 23.77％ and 43.27％ higher than CK1 (P＜0.05),respectively.It was concluded that the over-expressing of TrxS could alleviate efficiently the oxidative damage caused by artificial ageing,and increase the artificial ageing resisitance of transgenic bayley seeds.%为探索TrxS基因对转基因大麦种子耐贮藏能力的影响,以转TrxS基因大麦纯合株系Y002及其非转基因受体(CK1)为材料,采用高温高湿老化处理法,研究了TrxS基因过表达对转基因大麦种子耐贮藏性的影响.结果表明:(1)与非老化处理(CK2)相比,老化处理导致大麦种子发芽率和发芽势显著下降(P＜0.05),转基因株系Y002种子发芽率和发芽势的降低速率慢于非转基因种子(CK1),处理3d时Y002种子的发芽势和发芽率分别比CK1高20.00％和22.20％(P＜0.05)；(2)大麦种子中MDA、羰基含量和相对电导率等氧化损伤指标均随着老化处理时间的延长而增加,转基因株系Y002的上述指标增加率普遍低于CK1,处理3d时Y002的MDA含量、羰基含量和电导率分别比CK1低22.69％、15.02％、17.75％(P＜0.05)；(3)在老化处理条件下,转基因种子的抗氧化酶活性高于CK1,处理3d时Y002的CAT活性与处理2d的POD活性分别比CK1高23.77％和43.27％ (P＜0.05).以上结果说明,TrxS过表达能有效缓解高温高湿处理对大麦种子造成的氧化损伤,增强转基因大麦种子的抗老化能力.