摘要
植物的耐盐性是一个多基因控制的复杂性状,将多个耐盐相关基因导入同一植物更有助于提高植物的耐盐能力。运用农杆菌介导法向转AtNHX1(拟南芥Na+/H+逆向运输蛋白编码基因)的番茄(Lycopersicumesculentum L.Moneymaker’)株系X1OEA1自交二代植株(T2)中转入山菠菜甜菜碱醛脱氢酶基因(BADH)。PCR、Southern、RT-PCR和甜菜碱含量分析结果表明,BADH已经整合到番茄基因组中,并在转基因植株中转录和翻译表达。叶绿素荧光(Fv/Fm)、相对电导率(Rc/Rc’)、叶绿素含量(Chla+b)、叶绿素a/b比(Chla/b)、光合速率(Pn)测定结果表明,200mmol·L-1NaCl胁迫下,双转化的番茄植株各项生理指标均优于单转化AtNHX1的番茄。转双基因植株TT0-2随着NaCl浓度的增加,Fv/Fm值下降幅度最小;相对电导率与非胁迫条件下相比增加了3.6倍,而单转化AtNHX1的T2增加了4.2倍;与转单基因植株T2相比,茎部干重、鲜重分别增加12.5%、19.8%;叶部干重、鲜重分别增加22.5%、14.0%,差异达显著水平。初步证明双基因转化有助于增强番茄的耐盐性。同时对番茄的转化系统进行优化的结果表明,使用抗生素特美汀的转化效率明显高于头孢霉素的。
To evaluate the effects of combined salt tolerant mechanisms, BADH gene from Atriplex hortensis was introduced into the T2 generation of transgenic tomato （L. esculentum ‘Moneymaker’） line XIOEAI containing AtNHX1 by Agrobacterium tumefaciens mediated transformation. PCR, Southern blot, RT-PCR and betaine measurement indicated that BADH was integrated into the genome of XIOEAI and functioned properly. Physiological responses of the double transformant to 200 mmol·L^-1 NaCl treatment, reflected by photochemical efficiency of PS Ⅱ （Fv/Fm）, relative electronic conductivity （Rc/Rc＇）, chlorophyll content （Chla＋b, Chla/b） and net photosynthetic rate （Pn）, were better than those in XIOEAI. The double gene transformed tomato TT0-2 showed the least decrease of Fv/Fm value while the salt concentration increased gradually, and the relative electronic conductivity of TT0-2 and XIOEAI line T2 plant were 3.6 and 4.2 times higher under 200 mmol·L^-1 NaCl treatment compared with normal condition. The stem＇s dry weight and fresh weight of TT0-2 were 12.5% and 19.8% higher than that of XIOEAI line T2 plant, respectively, at the same time, the leaves＇ dry weight and fresh weight of which were 22.5% and 14.0% higher. The results indicated that multigene transformation could further improve salt tolerance of plant. Furthermore, the transformation system of tomato was optimized. The results have proved that Timentin is a better antibiotic than cefotaxim for the effective transformation of tomato.
出处
《中国农业科学》
CAS
CSCD
北大核心
2005年第8期1636-1644,共9页
Scientia Agricultura Sinica
基金
国家"863"计划(2003AA627010)
转基因专项(JY03-A-20-01)资助
