干旱高温胁迫下转基因水稻的生理变化

用PEG-6000、38℃及PEG-6000+38℃胁迫处理携带谷胱甘肽转移酶(GST)和过氧化氢酶(CAT1)的转基因水稻和非转基因水稻(Oryza sativa L.cv中花11), 并比较分析了二者在胁迫下的生理指标和抗氧化酶活性变化.结果显示,在单一PEG及PEG和高温复合胁迫下,植株生长、光合参数和相对含水量的降低幅度及H2O2和MDA(malon dialdehyde)的积累量在非转基因水稻与转基因水稻之间都有显著差异.在这2种胁迫下,转基因水稻的可溶性糖含量及CAT和POD (Peroxidase) 活性与非转基因水稻也有显著差异.这些结果表明,谷胱甘肽转移酶(GST)和过氧化氢酶(CAT1)的表达减轻了转基因水稻在单一干旱及干旱+高温复合胁迫下的伤害.

Physiological Changes of Transgenic Rice under Drought and Heat Stress

The changes of some physiological parameters and antioxidant enzymes in transgenic rice ( Oryza sativa L.cv Zhonghua No.11) carrying glutathione S transferase (GST,EC.2.5.1.18) and catalase1 (CAT1,EC.1.11.1.6) and non transgenics were compared under PEG 6000 or 38℃ and their combination.The results showed that the significant decreases in plant growth,photosynthetic parameters and relative water content occurred in non transgenics compared to the transgenics under just PEG 6000 and the combination of PEG 6000 and heat stress.The oxidative damage in terms of malondialdehyde and H 2O 2 content was markedly higher in non transgenics than that in the transgenics following the applied stresses.However,the soluble sugar concentration and the activities of CAT and peroxidase (POD,EC 1.11.1.7) were significantly higher in the transgenics relative to non transgenics subjected to drought and the stress combination.These results implied that the GST and CAT1 transgene mitigated oxidative damage caused by drought and the combined stress.