Biosafety aspects of deliberate release of recombinant microorganisms in the agricultural environments

Recombinant or genetically modified microorganisms (GMMs) have high potential to provide valuable services to the agriculture sector. For example, it is possible to produce GM microbial biopesticides and biofertilizers with higher efficiencies, high quality animal feed supplements (enzyme sources and probiotics), functional and enriched foods, and also bioremediation of polluted agricultural environments. Regarding the high potential and proven advantages of these kinds of microorganisms, reduction of the concerns about their risks will open the way for their commercialization in the near future. During risk assessment of GMMs, some characteristics, including the level of durability, gene flow and possible horizontal gene flow to other microbial flora in the environment, possible effects on non-target organisms - especially useful microorganisms in the rhizosphere – and, finally, human health and food safety concerns, must be evaluated. Although, numerous studies have been dedicated to the environmental risk assessment of GM plants, the knowledge about gained is unfortunately still insufficient, causing their large scale production and commercialization to be very slow. This paper reviews possible benefits of GMMs and also their possible environmental effects related to divers agricultural environments with emphasis on GM PGPRs (biofertilizers) and GM microbial agents used as biopesticides for control of plant pests and diseases. Finally, it will be argued that the benefits and environmental effects of GMMs should be compared with the negative effects of chemical fertilizers and pesticides which are widely used in agriculture sector, and also with the potential effects of wild type microorganisms.