转Bt基因南林895杨抗虫性及对土壤微生物影响分析

Analysis on Insecticidal Activity of Bt Transgenic Populus deltoides × P.euramericana cv'Nanlin895'and Its Effects on Soil Microorganism

以转Bt基因南林895杨株系B1、B4、B17、B21扦插苗为试验材料,分析其在室内和野外自然条件下对靶标害虫杨小舟蛾幼虫的抗虫性。结果表明:转Bt基因杨树4个株系均有一定的杀虫活性,其中株系B21对杨小舟蛾1龄幼虫12 d校正死亡率高达95.3%;虫试表明转Bt基因杨树各株系扦植苗在野外自然条件下的12 d幼虫校正死亡率8月份为35.0%88.8%,9月份为40.5%95.3%。用转Bt基因杨树叶片饲养杨小舟蛾,对照植株杨小舟蛾幼虫化蛹率为83.3%96.0%,而转Bt基因株系幼虫化蛹率为8.0%76.7%,二者有显著差异。转Bt基因杨树对杨小舟蛾幼虫的生长发育有抑制作用,饲喂8 d后害虫取食量、体质量增长速率显著低于对照。此外,为了解转Bt基因杨树对土壤微生物的影响,对转Bt基因杨树株系及对照进行了根际土壤微生物可培养类群的分析,初步结果显示:转Bt基因杨树根际土壤微生物中细菌、真菌、放线菌的数量与对照比较无显著差异。

During the growing season of 2011,the leaves of four Bt transgenic clones B1,B4,B17 and B21 of Populus deltoides × P.euramericana cv.＇Nanlin895＇ were exposed to the target pest larvae of Micromelalopha troglodyta to assess the insecticidal activity of Bt transgenic P.deltoides × P.euramericana cv.＇Nanlin895＇ under laboratory and field conditions.It was showed that all the clones had certain insecticidal activity against target pests.The corrected mortality of the target pest feeding on clone B21 was as high as 95.3%.The corrected mortalities in August and September were 35.0%-88.8% and 40.5%-95.3% respectively under field conditions.The pupation ratio was 83.3%-96.0% in CK,while in transgenic poplar that was 8.0%-76.7%,showing a significant difference between them.The development of target larvae was inhibited by Bt transgenic P.deltoides × P.euramericana cv.＇Nanlin895＇.After 8 days＇ feeding,the intake and growth rate of target larvae were significantly lower than that of the CK.The effect of Bt transgenic poplars on microorganisms in rhizosphere soil was also studied and no significant difference was found in the quantities of bacteria,fungi,and actinomycete between the transgenic and non-transgenic poplars,suggesting no negative influence on the soil microorganism system.