苏云金芽胞杆菌基因工程菌WG-001和1125BG在盆栽土壤中的安全性评估

自从遗传改造微生物诞生以来,其安全性问题受到了持续关注和研究.本文报道了苏云金芽胞杆菌基因工程菌WG-001和1125BG在盆栽大白菜的土壤环境中的安全性评估结果.实验结果表明:当用工程菌WG-001和1125BG分别以1013 cfu/cm2和1010 cfu/cm2的高土壤密度喷洒盆栽大白菜后,工程菌菌数迅速上升而后逐渐下降,最后分别以相对较低的菌数水平(105 cfu/g干土样和106 cfu/g干土样)在实验土壤中稳定存在;对土壤中土著细菌群落在有限时间(15d)内产生了一定影响,而对土著真菌与放线菌无显著影响;未发现工程菌WG-001中特异基因发生丢失;未检测到工程菌WG-001和1125BG中特异基因(WG-001为cry1Aa和cry1Ac,1125BG为gfp)向土著细菌、真菌、放线菌和盆栽大白菜的水平转移.本文实验结果显示,高密度喷洒的两种工程菌未显著影响实验土壤环境,具有很高的安全性.同时发现以不同的喷药量喷洒两种工程菌后,在盆栽土壤中其存活水平、菌数降低的速率以及对土著细菌的影响能力都表现出不同的特点.

Biosafety evaluation of genetically engineered Bacillus thuringiensis WG-001 and 1125BG in potting soil

This paper is inclined to report the authors' research on the biosafety evaluation of the genetically engineered Bacillus thuringiensis WG-001 and 1125BG in the soils with the Chinese cabbages being planted in.As is known,since the generation of genetically modified microorganisms(GMOs),its bio-safety has been given serious consideration.The results of our research indicate that,after spraying the WG-001 and 1125BG to potted Chinese cabbages at high density,the numbers of WG-001 and 1125BG in the potting soil in fact increased quickly and then decreased gradually,and finally keeping at relatively low levels with 105 cfu/g fresh soil and 106 cfu/g fresh soil,respectively.The indigenous bacteria could be influenced at a certain extent in limited time(15 d).However,the indigenous fungi and actinomycetes prove not to have been influenced noticeably. At the same time,the specific genes of WG-001 had not lost and the horizontal transfer of the characteristic genes(cry1Aa and cry1Ac of WG-001,and gfp of 1125BG) had not been detected from the genetically engineered B.thuringiensis to the indigenous microorganisms or potted Chinese cabbages.Thus,it can be concluded that the genetically engineered B.thuringiensis WG-001 and 1125BG does not have any ability to influence observably the ecosystem of the soil potting Chinese cabbage.And,in turn,it has been found that,after spraying the B.thuringiensis WG-001 or 1125BG with different quantities,the numbers,the declining speed and the ability to influence the indigenous bacteria of existing WG-001 or 1125BG in the soil may demonstrate different characteristic features.