基因组学与应用生物学

目前仓库贮烟中烟草甲对烟叶危害较为严重,本研究试图通过筛选对烟草甲幼虫具有较高杀灭活性的苏云金芽孢杆菌菌株,以有效控制贮烟仓库中烟草甲虫害。我们收集了广西贮烟仓库中贮存的广西百色和贵州兴义生产的50份烟叶样品,利用醋酸钠筛选法共分离到芽孢杆菌137株,其中4株可能是苏云金芽孢杆菌,其菌株分离率和出菌率分别为2.91%和8.00%。扫描电镜显示GXZY032菌株能产生大量球形伴孢晶体蛋白,进一步的生理生化测定结果显示,菌株GXZY032与模式菌株Btt之间的生理生化反应特性表现基本相同,但在蔗糖发酵、淀粉水解、脲酶水解和卵磷脂酶4个项目反应上差异较大。对GXZY032菌株进行了生物毒力测定,发现该菌株对烟草甲幼虫的校正死亡率为72.5%,比模式菌株Btt的杀虫活性(86.25%)略微偏低。本研究结果将为后续发掘有效控制烟草甲幼虫的Bt菌株提供实验材料,为挖掘新型杀虫蛋白基因提供研究基础。

At present,the tobacco leaves in the warehouse storage were damaged seriously by tobacco beetle(Lasiodermaserricorne),in this study,we tried to screening Bacillus thuringiensis strains with highly killing activities against tobacco beetle larva for effectively controlling tobacco beetles in warehouse storage.Here,50 samples of tobacco leaf produced by Baise and Xingyi were collected from Guangxi Tobacco Storage Warehouse,of which 137 bacillus strains were isolated by using sodium acetate screening method.Fortunately,four of the strains with Bacillus thuringiensis(Bt) characteristics were screened,the strain isolating and bacteria average rate was of 2.91% and 8.00%,respectively.Scanning electron microscopy(SEM) showed that GXZY032 strains can produce a large number of spherical with parasporal crystal proteins,further physiological and biochemical determination results showed that the physiological and biochemical reaction of the strain GXZY032 and the standard strain(Btt) was similar by and large,except in sucrose,starch hydrolysis fermentation,urea enzyme hydrolysis and lecithin enzyme,their response were different.Finally,the biological toxicity of strain GXZY032,the preliminary findings showed that the corrected mortality of strain GXZY032 was 72.5% against tobacco beetles larva,its insecticidal activity was slightly lower than standard strain Btt(85.14%).The results of this study will provide experimental materials for the subsequent exploring of Bt strains that effectively control tobacco beetles larva.and laid a research foundation for the new insecticidal protein genes.