转AtNHX1基因杨树Tr品系的耐盐性研究  

Salt tolerance of transgenic poplar by the introduction of AtNHX1 gene

作　　者：姜超强[1] 郑青松[1] 刘兆普[1] 徐文君[2] 李洪燕[1] 李青[1] 

机构地区：[1]南京农业大学资源与环境科学学院/江苏省海洋生物学重点实验室,南京210095 [2]江苏省质量技术监督局,南京210008

出　　处：《植物生态学报》2010年第5期563-570,共8页Chinese Journal of Plant Ecology

基　　金：国家863计划重点项目(2007AA091702)资助

摘　　要：以不同盐分强度处理欧美107杨(Populus×euramericana‘Neva’)(Wt)和转拟南芥液泡膜Na+/H+逆向转运蛋白基因AtNHX1欧美107杨新品系(Tr)幼苗,揭示Tr和Wt两品系幼苗耐盐性的差异,探索拟南芥液泡膜Na+/H+逆向转运蛋白基因AtNHX1对提高杨树耐盐能力的效应。结果表明:低盐处理下,Wt植株生长明显受到抑制,其干重显著低于对照,盐分强度加大后,抑制作用更大,其干重只有对照的50%;而Tr植株在低盐处理下干重与对照差异不显著,高盐处理时其干重为对照的74%。同时,不同盐度处理下,Tr的干重均显著高于Wt,且随着盐度升高,两品系间植株干重差异增大。盐处理后,Tr植株叶片叶绿素和类胡萝卜素的含量均显著高于Wt,并能维持较高的净光合速率(Pn)和PSII最大光化学效率(Fv/Fm);在盐处理下虽然Tr叶片和根系均较Wt积累了更多的Na+,但同时也维持了更高的K+和K+/Na+比率,而且叶片对K+选择性的运输明显高于Wt;同时,Tr叶片MDA含量和电解质渗漏率显著低于Wt。可见,在盐处理下转AtNHX1植株较未转基因植株维持了更高的生长量、光合色素、光合能力和叶片质膜稳定性,说明AtNHX1的转入能够显著提高欧美107杨的耐盐性。Aim Our objective was to test whether the overexpression of the Arabidopsis thaliana tonoplast Na^＋/H^＋ antiporter gene, AtNHX1, can improve salt tolerance in poplar. Methods Transgenic and wild-type poplar （Populus × euramericana ＇Neva＇） were subjected to low salt and high salt treatments. We investigated the effects of NaCl on the transgenic and wild-type poplar by measuring growth parameters, chlorophyll （Chl） and carotenoid （Car） content, net photosynthetic rate （Pn）, maximal photochemical efficiency ofPSII （Fv/Fm）, ion content, leaf malondialdehyde （MDA） and electrolytic leakage after 30 days. Important findings Compared with the control, the growth of wild-type plants was restrained significantly in the presence of both low salt and high salt. The dry weight of wild-type plants was significantly lower under salt stress than that of control, the dry weight decreased gradually with increasing NaCl concentration and their dry weight under high salt was just 50% of the control. However, the dry weight of transgenic plants in low salt was similar to the control up to the high salt treatment, where their dry weight was 74% of the control. Moreover, the dry weight of transgenic plants was significant higher than that of wild-type in both NaCl treatments, and the discrepancy of dry weight was increased with increasing NaCl concentration. In the presence of NaCI, Chl and Car content of transgenic plants were significantly higher than that of wild-type, and the transgenic plants maintained a remarkably high Pn and Fv/Fm. Although these transgenic plants accumulated more Na＋ in their roots and leaf tissues under salinity conditions compared with the wild-type plants, they absorbed more K^＋ and maintained a higher K^＋/Na^＋ ratio. Moreover, these transgenic plants kept a lower MDA and electrolytic leakage level than that of wild-type. These findings indicate that transformation of AtNHX1 gene into poplar can confer plants more tolerance to salinity than wild-type poplar by mainta

关 键 词：ATNHX1 离子区域化 欧美杨 耐盐性 转基因植物 

分 类 号：S792.11[农业科学—林木遗传育种]