Abstract:

We studied the insectresistance selectivity of transgenic hybrid poplar 741 that carried the different Bt genes to different type pest by the molecule detection, insectresistant test and insectical protein expression. The seven transgenic subclones of transgenic hybrid poplar 741 carrying the BtCry3A gene and two transgenic subclones of transgenic hybrid poplar 741 carrying two insectresistant genes (BtCrylAc+API) were used. Result showed that two BT genes respectively and steadily existed in different transgenic hybrid poplar 741 The contents of toxic protein in two individual plants carrying insectresistant genes (BtCrylAc) were respectively 0.012 7% and 0.009 9%. The content of toxic protein in plant pb29 was higher than in plant pb17 and the former was also more resistant to the pests than the latter. The content of toxic protein in five individual plants carrying insectresistant genes (BtCry3A) was between 0.067 8% and 0.152 1%, and there was variation in the protein content among the individual plants. The insectical protein expression content of BtCry3 was very high and was 10 times higher than that of BtCry1 The laminae of transgenic hybrid poplar 741 carrying two insectresistant genes (BtCrylAc+API) were used to feed Lepidoptera pests of Plagiodera versicolora (Laicharting), the larval mortality was up to between 28.4% and 42.8%, and it has not obviously differentia between transgenic subclones and in contrast. The laminaes of different transgenic subclones carrying the BtCry3A gene were feed to the larva of Plagiodera versicolora (Laicharting), it put up a high insectresistantce, the larval mortality was up to 100% promptly within 1-2 days; The larval mortality was between 0 and 42.86% when the larva of Clostera anachoreta (Fabricius) were feed. It has not obvious insectresistantce and it has little differentia than in contrast.

Key words: transgenic insect resistance hybrid poplar 741, foreign gene, Bt toxic protein, insectresistance