转人工改造的Bt Cry1Ac 基因中林美荷杨的 获得及其抗虫性分析

中林美荷杨具有适应性强、雄性不飞絮、速生丰产和耐瘠薄等优良性状，然而受到一些害虫的危害，造成树苗生长不良，严重影响苗木的产量和质量。采用中林美荷杨的叶片和节间组织作为外植体，通过根癌农杆菌(Agrobacterium tumefaciens)介导法将人工改造后的抗虫基因Bt Cry1Ac 导入杨树基因组中。对所获得的中林美荷杨转基因植株进行PCR、Southern blotting 和Real-time PCR 等分子生物学检测，结果表明Bt Cry1Ac 基因多以单拷贝整合到受体植物基因组中，其中7 个转基因株系显示外源基因有较高的转录表达。经过实验室喂虫鉴定，筛选出2 个抗性效果好的株系。中林美荷杨转抗虫基因株系的获得为该品种绿化造林和推广提供了条件。

Recovery of Transgenic Populus Plants with Modified Bt Cry1Ac Gene and Their Insect-resistance Assay

Populus sp. is a fine variety with wide adaptability, male without catkins, fast-growing, high yield and enduring barren. However, pests damage the production and quality of this wood. To enhance insect resistance of Populus sp., Cry1Ac gene was introduced into poplar via Agrobacterium-mediated transformation with explants of leaves and internodes. The integration of the target gene into the poplar genome was identified by PCR and Southern blotting analyses. Real-time PCR analyses indicated the expression of Cry1Ac gene in seven transgenic poplar plants. Resistance evaluation by raising insect with detached leaves showed that 2 of 7 transgenic lines were superior in Hyphantria cunea resistance. Transgenic poplar plants with insect resistance facilitate afforestation and extension of the variety.