转基因白桦对舞毒蛾的抗性研究

Resistance of Transgenic Betula platyphylla to the Defoliator Lymantria dispar

白桦（Betula platyphylla）是我国北方的乡土树种，主要分布在东北、华北、西北。由于白桦材质优良、材色洁白、表面光滑，是人造板材的优质原材料，在林业生产上具有重要经济价值。但在白桦天然次生林和人工林培育中常常遭受各种害虫的危害，降低了其材积生长和木材质量，影响木材的利用率，给林业经济造成巨大损失。以往对白桦害虫的控制措施多采用化学防治手段，不仅造成环境污染、杀伤天敌、破坏生物多样性和生态平衡，同时导致害虫产生抗药性和防治效果下降。利用基因工程的方法，将杀虫基因导入白桦，使其获得持久、稳定的抗虫性能，是害虫生物防治的新途径之一（Katia et al．，1993；张锐等，2001；程业明等，2001；金风，2004）。本文以作者转化的抗虫基因白桦为材料（王志英等，2005），对舞毒蛾幼虫生长发育的影响和抗虫性进行了测定，目的是为抗虫白桦苗木定向培育奠定科学基础。

The paper report the results of study on the resistance of transgenic tree Betula platyphlla with BtC peptide and spider insecticide peptide gene to the defoliator Lymantria dispar, the result showed that the transgenic B. platyphylla could prolong the duration of L. dispar larvae obviously. The Developmental Relative Value of larvae of L. dispar from 1^st instar to 3^rd instar feeding on birch positive to GUS or that negative to GUS were 66.8, 72.5 % ; 90.5, 96.4 % ; 81.6, 92.5 %, respectively. Larvae in the control could finish development normally but treated larvae didn＇t develop to 5^th instar. The transgenic tree could repressed the pest larvae mass obviously. The mean body mass of the larvae after 40 d＇ s feeding on non-transgenic birch were 6.75 and 7.43 times of those feeding on two type of transgenic birch, respectively. The exuviations index of the larvae after 30 d＇s feeding on two type of transgenic birch were 2.933 and 3. 038 respectively, both lower than that of control of 3. 323, indicating transgenic birch could restrain the exuviations of the larvae of gypsy moth to some extent. The feeding capacity of the larvae after 30 d＇s feeding on non-transgenic birch were 0.641 0 g· head^- 1 and 0.529 1 g· head^-1 more than those feeding on two type of transgenic birch, respectively. Meanwhile, the corrective mortality of the larvae feeding on two types of transgenic birch were 94.64 % and 72.70 %, respectively, indicating that transgenic birch had the high lethal effect on gypsy moth larvae.