Biotechnology alongside the introduction of genetically modified (GM) crops is constantly providing new opportunities for increasing crop productivity and tackling problems in agriculture, such as diseases, pests and weeds, abiotic stress and nutritional limitations of stopple food crops. Crops possessing new traits enabling the use in pharmaceutical production are also being generated. As GM crops are being introduced into various locations with different ecosystems, agriculture, biodiversity and agriculture practice, a scientifically based understanding of the environmental effects of GM crops cultivation would assist decision markers worldwide in ensuring environmental safety and sustainability. The main important environmental assessment of GM crops deals wit their putative invasiveness, vertical and/or horizontal gene flow, effects on biodiversity and the impact on other products. These investigations are all highly interdisciplinary and complex. This paper deals with some of the most important problems related to entering GM crops into the environment, such as plant protection, ecological effects of HRCs, gene flow, biodiversity, stress, ecological risks of Bt crops, effects on soil ecosystems etc. There is a clear need to further assess the severity, magnitude and scope of risks associated with the massive field deployment of transgenic crops. When assessing GMC inter-relation with the existing cultivars, an increased knowledge base underpinning the development of GMC will provide greater confidence in plant science while assessing the risks and benefits of releasing such crops
