Dunfield Kari E, Germida James J
Department of Soil Science, University of Saskatchewan, Saskatoon, SK, Canada S7N 5A8.
J Environ Qual. 2004 May-Jun;33(3):806-15. doi: 10.2134/jeq2004.0806.
Transgenic or genetically modified plants possess novel genes that impart beneficial characteristics such as herbicide resistance. One of the least understood areas in the environmental risk assessment of genetically modified crops is their impact on soil- and plant-associated microbial communities. The potential for interaction between transgenic plants and plant residues and the soil microbial community is not well understood. The recognition that these interactions could change microbial biodiversity and affect ecosystem functioning has initiated a limited number of studies in the area. At this time, studies have shown the possibility that transgenes can be transferred to native soil microorganisms through horizontal gene transfer, although there is not evidence of this occurring in the soil. Furthermore, novel proteins have been shown to be released from transgenic plants into the soil ecosystem, and their presence can influence the biodiversity of the microbial community by selectively stimulating the growth of organisms that can use them. Microbial diversity can be altered when associated with transgenic plants; however, these effects are both variable and transient. Soil- and plant-associated microbial communities are influenced not only by plant species and transgene insertion but also by environmental factors such as field site and sampling date. Minor alterations in the diversity of the microbial community could affect soil health and ecosystem functioning, and therefore, the impact that plant variety may have on the dynamics of the rhizosphere microbial populations and in turn plant growth and health and ecosystem sustainability, requires further study.
转基因植物或基因改造植物拥有赋予诸如抗除草剂等有益特性的新基因。转基因作物环境风险评估中最不为人所了解的领域之一是它们对与土壤和植物相关的微生物群落的影响。转基因植物与植物残体以及土壤微生物群落之间相互作用的可能性尚未得到充分了解。认识到这些相互作用可能会改变微生物生物多样性并影响生态系统功能，已在该领域启动了数量有限的研究。目前，研究表明转基因有可能通过水平基因转移转移到本地土壤微生物中，尽管尚无证据表明这种情况在土壤中发生。此外，已证明新蛋白质会从转基因植物释放到土壤生态系统中，其存在可通过选择性刺激能够利用它们的生物体的生长来影响微生物群落的生物多样性。与转基因植物相关时，微生物多样性可能会改变；然而，这些影响既多变又短暂。与土壤和植物相关的微生物群落不仅受植物种类和转基因插入的影响，还受田间地点和采样日期等环境因素的影响。微生物群落多样性的微小变化可能会影响土壤健康和生态系统功能，因此，植物品种对根际微生物种群动态进而对植物生长、健康和生态系统可持续性可能产生的影响，需要进一步研究。
