Do transgenic plants affect rhizobacteria populations?
Bottom Line: The rapid development of agricultural biotechnology and release of GMPs have provided many agronomic and economic benefits, but has also raised concerns over the potential impact these plants might have on the environment.This minireview summarizes the results of various experiments that have been conducted to date on the impact of GMPs on rhizobacteria.Both biological and technical parameters are discussed and an attempt is made to determine if specific rhizobacterial responses exist for the different categories of GMPs developed to date.
Affiliation: Department of Biology, Université de Moncton, Moncton, Canada. email@example.comShow MeSH
Mentions: One of the most striking conclusions concerning risk assessment studies performed on the impact of GMPs on rhizobacteria is that so far a wide variety of techniques have been used to examine numerous parameters and confusion still exists as to which information is really relevant in this context. To date, most studies investigating the impact of GMPs have shown at least minor effects on the abundance and/or the diversity of rhizobacteria (Fig. 1). Despite the limited number of studies performed on this topic, we can now conclude with certainty that the effects observed are not artefacts. Clear rhizobacterial community changes have been shown in the rhizosphere of a variety of plants using different transgenes. The results obtained were reproducible and, in many cases, rhizobacterial responses to different categories of GMPs appeared more dependent on the nature of the transgene used than any other considerations. However, based on the limited information presently available in the literature, we can suspect that these effects, although not negligible, can be considered ‘minor’ when compared with other ‘normal’ sources of variation, such as field site, soil type, seasonal variation, plant growth stage, etc. Agricultural practices, such as irrigation, crop rotation, tillage and use of herbicides and pesticides, have been shown to influence rhizobacteria populations with similar impact and in many cases more importantly than plant genetic transformation. So far, no study has been able to clearly show a long‐term negative effect of plant genetic transformation on rhizobacterial populations. Regardless of the plant species, transgenes and growth conditions used, all rhizobacteria community changes reported during active growth seasons have diminished to undetectable levels in a few weeks or months following plant harvesting.
Affiliation: Department of Biology, Université de Moncton, Moncton, Canada. firstname.lastname@example.org