cry transgenic poplar and risks analyses

Problems, such as the impact on biodiversity and the potential escapes of the trans-genes into wild populations can be amplified in the case of long-lived forest species. Thus, studies of possible environmental impacts of transgenic forest plants (poplar) in the forest environment are important. Although a number of studies have been carried out so far considering the use of transgenesis for genomic studies, only little is known about biosafety issues of transgenic trees foreseen for breeding purposes. As a model transgenic tree system, we have produced Populus alba and P. tremula transgenic lines carrying the cry gene from Bacillus thuringiensis. These transgenic are under screening to unravel possible pleiotropic metabolic effects in the transgenic trees following cry gene expression. It is also not known how the use of cry-transgenic poplars affects composition and activities of soil microbial communities which affect soil health. In addition to foreign DNA, proteins from crytransgenic poplars can be released into the soil via plant residues and their persistence can constitute not only a selective pressure towards the target organisms, but also a possible threat for non-target ones with unpredictable consequences on the food chain sustained by these organisms. The work is carried out on an integrated and multidisciplinary approach (physiology, soil microbiology and biochemistry, genomic, proteomic, and microscopy), involving different scientific groups with different and specific expertise, to assess the mentioned biosafety issues important for forest trees. The screening of the transgenic plants is in course, and the evaluation of the number copy of the inserted gene as well as expression of the inserted gene is under evaluation.