NaCI胁迫对转基因杨树外源基因表达的影响

以具高抗虫性的转抗虫基因‘74l杨’及在此基础上转入了发根农杆菌融质粒T-DNA株系的组培苗为材料，研究了转基因株系BtCrylAc抗虫基因和发根基因的表达及其对NaCI胁迫的反应。结果表明，转入Ri质粒T-DNA上的rol基因后，导致苗木根系数目增加，根系长度减小，IAA和GA含量显著提高，抗虫BtCrylAc基因编码的毒蛋白的表达量降低；随着NaCI胁迫强度的增加，苗高、根系数量、叶绿素含量及IAA、GA含量逐步降低，而根系的长度加大，Bt毒蛋白含量显著提高，表明NaCI胁迫使转基因杨外源Bt毒蛋白基因的表达增强，而发根农杆菌．Ri质粒T-DNA的表达下降。

Effects of NaCI Stress on the Exogenous Gene Expression in Transgenic Poolar Plants

The expressions of BtCry1Ac insect-resistance genes and rhizogenesis genes and their response to NaCl stress were studied using tissue culture plants of high transgenic insect-resistant 'poplar 741' and transpolygenes 741 (insect-resistant genes and T-DNA of Ri plasmid). The results showed that IAA and GA contents increased quickly, plant root number increased and root length reduced after rhizogenesis and hormone synthesis related gene in Ri T-DNA were inserted into the genome of poplar (Figs.2, 3, 8 and 9). Plant height, root number, chlorophyll content, IAA and GA contents decreased gradually with an increase in NaCl stress intensity (Figs.1, 2, 4-6, 8 and 9). Apiece index change extent of transgenic rol gene plant was smaller than transgenic Bt gene plant and non-transgenic plant. Bt toxin protein content of transgenic rol gene plant increased significantly under NaCl stress (Fig.7). Our results indicate that the expressions of the foreign genes changed with the changes of the environmental conditions.