转菊芋凝集素基因烟草对桃蚜的抗虫性研究

研究了菊芋凝集素基因(hta)对同翅目害虫的抗性。4个同源的hta基因置于CaMV35S启动子和nos终止子的控制下，通过根癌农杆菌(Agrobacterium tumefaciens)介导法被转入烟草。Southern杂交显示，外源hta被整合到转化烟草的基因组中。Northern杂交表明hta mRNA在转基因烟草中进行了表达。利用桃蚜进行的抗虫试验表明，转基因烟草对桃蚜具有抗性。同对照植株相比，T0代转基因烟草使桃蚜的平均虫头数下降70％．在T0代转基因烟草中，转hta-b和hta-c基因烟草对桃蚜繁殖的抑制率分别为53．0％、64．6％，同时，对桃蚜若虫的发育具有明显的抑制作用。

Transformation of Tobacco with Genes Encoding Helianthus tuberosus Agglutinin (HTA) Confers Resistance to Peach-Potato Aphid (Myzus persicae )

We investigated the effects of hta gene encoding Helianthus tuberosus agglutinin (HTA) on an insect in the order Homoptera. Homologous cDNAs of hta-a, hta-b, hta-c and hta-d with CaMV35S as promoter were introduced into tobacco via Agrobacterium tumefaciens-mediated procedure. Southern blotting results showed that exogenous hta gene was inserted into the genome of host plants, and Northern blotting analysis confirmed that hta was expressed in transgenic plants. Bioassay with peach-potato aphid (Myzus persicae) demonstrated that transgenic plants had deleterious effects on it. The average population of aphid fed with transgenic plants of T_0 generation during an 11-day assay decreased by 70%, when compared with controls. In transgenic plants of T_1 generation, aphid fecundity inhibitions were 53.0% (hta-b) and 64.6% (hta-c) respectively. The development of aphids was notably retarded. We conclude that hta could be a novel and promising candidate for plant transgenic engineering against homopteran insect pests.