Trxs基因对啤酒大麦籽粒灌浆后期抗氧化能力和荧光参数的影响

Effects of Trxs on Antioxidative Ability and Fluorescence Parameters of Transgenic Barley at Late Grain-filling Stage

为了深入探索Trxs基因的功能,给转基因大麦育种提供理论依据,以啤酒大麦品种Harrington及其过量表达硫氧还蛋白S基因(Trxs)的转基因大麦株系为试验材料,对籽粒灌浆后期旗叶中还原型谷胱甘肽(GSH)含量、抗坏血酸过氧化物酶(APX)活性、叶绿素荧光特性以及不同发育阶段籽粒中GSH含量和产量性状进行研究。结果显示:(1)籽粒灌浆后期转基因大麦旗叶GSH含量与APX活性显著高于非转基因对照;(2)花后15 d时各测定时间点和籽粒灌浆后期不同测定时间转基因大麦旗叶叶绿素荧光参数Fv/Fm与Fv/Fo值普遍高于对照;(3)转基因大麦的产量性状优于对照,其千粒重、单株穗数和单株产量平均分别比对照提高了12.29%、34.34%与41.01%。这些结果表明,Trxs通过影响旗叶和籽粒中GSH含量和旗叶中APX活性,提高了籽粒灌浆后期转基因啤酒大麦抗逆境胁迫的能力,改善了啤酒大麦转基因株系在籽粒灌浆后期的光合性能,有利于提高了单株产量。

The barley variety,Harrington and its transgenic line over-expressing Trxs were used to determine glutathione（GSH） content both in flag leaves and immature seeds,ascorbate peroxides（APX） activities and chlorophyll fluorescence parameters in flag leaves at late grain-filling stage,and yield traits.The results showed that（1） over-expressing of Trxs could increase GSH content in both flag leaves and seeds,and APX activities in flag leaves.（2） in comparison with control,the transgenic barley had larger values of key chlorophyll fluorescence parameters,such as Fv/Fm and Fv/Fo.（3） the 1000-grain weight,spikes per plant and grain yield per plant of the transgenic line were 12.29%,34.34% and 41.01% higher than that of the control,respectively.It may be concluded that over-expressing of Trxs efficiently increased the GSH content in both leaves and seeds and APX activity of flag leaves,and thus enhanced the antioxidative ability,improved photosynthesis function and yield formation at late grain-filling stage.The results showed the possibility that transgenic barley could be applied in improving the tolerance to abiotic stresses.