《植物生理学报》 2010, 46(8): 808-816

超表达AVP1 基因提高转基因百脉根的耐盐性和抗旱性

程星*, 王燕雯*, 包爱科, 王锁民**

兰州大学草地农业科技学院, 兰州730020

通信作者：王锁民；E-mail: smwang@lzu.edu.cn；Tel: 0931-8910983

摘　要：

本研究以超表达拟南芥液泡膜 H+- 焦磷酸酶编码基因 AVP1 的转基因百脉根为材料, 对其耐盐性和抗旱性进行了检 测。结果显示: 在200 mmol•L-1 NaCl下处理或自然干旱7 d后, 转基因植株的生长虽然受到抑制, 但受抑程度明显低于野生 型植株, 前者叶片相对含水量比后者分别高18%和14%, 净光合速率分别高20%和21%, 而MDA含量则分别低35%和27%, 相对质膜透性分别低 28% 和 27%。此外, 随着盐和干旱胁迫的加剧, 与野生型植株相比, 转基因植株体内积累了更多Na+、 K+ 和Ca2+。以上结果表明, AVP1 基因的超表达可能提高了百脉根细胞Na+ 区域化能力, 既减轻了过量Na+ 对细胞质的毒害 作用, 也提高了植株的渗透调节能力, 从而增强了百脉根的耐盐性和抗旱性。

关键词：转基因百脉根; AVP1基因; 耐盐性; 抗旱性

收稿：2010-04-12   修定：2010-05-10

资助：“十一五”国家科技支撑计划(2008BADB3B01)和国家自然科学基金(30770347)。

Overexpression of AVP1 Enhanced Salt and Drought Tolerance of Transgenic Lotus corniculatus L.

CHENG Xing*, WANG Yan-Wen*, BAO Ai-Ke, WANG Suo-Min**

College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China

Corresponding author: CHENG Xing; E-mail: smwang@lzu.edu.cn; Tel: 0931-8910983

Abstract:

The Arabidopsis thaliana vacuolar H⁺-pyrophosphatase (H⁺-PPase) gene (AVP1) was overexpressed in Lotus corniculatus could enhance salt and drought tolerance of transgenic plants. The results indicated that the growth of transgenic lines was inhibited in the presence of 200 mmol·L^-1 NaCl or under a water-deprivation condition after 7 days, while the wild-type plants suffered from much more serious growth inhibition. Under 200 mmol·L^-1 NaCl or water-deprivation treatments, transgenic plants retained more water in leaves and higher photosynthesis activity compared with wild-type whereas the content of MDA and the relative membrane permeability of transgenic plants was lower than wild-type. Furthermore, under salt or water-deficit stress, transgenic plants accumulated more Na⁺, K⁺ and Ca²⁺ in their leaves and roots. These results demonstrated that overexpression of AVP1 gene might enhance compartmentalization of Na⁺ in vacuole, which not only reduced the damage of excess Na⁺in the cytosol under salt stress, but also enhanced the osmoregulation capacity of cells, and therefore improved salt and drought resistance of transgenic L. corniculatus.

Key words: transgenetic Lotus corniculatus; AVP1; salt resistance; drought resistance