Environmental impacts of transgenic Bt rice and non-Bt rice cultivars in northern Iran

In the future, rice production is likely to be impacted by climate change and associated risks including pest complexes and consumption of chemical inputs, thereby decreasing production at a regional scale and one of the major global concerns. In fact, among the biotic stresses, damage caused by insect pests, which can be categorized as either minor or major pests, can severely constrain the potential yield of rice. Hence, planting transgenic rice is considered a solution for reducing environmental and human health impacts. Therefore, in this research, life cycle assessment for environmental and human health impacts of transgenic and non-transgenic rice cultivars was considered. Hence, four transgenic lines (driven from back cross of Khazar cultivar with transgenic line of Tarom Molaii) along with conventional cultivars (non-transgenic parents) were cultivated under the standard of biosafety protocol in three isolated sites in north of Iran in 2016. In order to conducted life cycle assessment, first, the results of each site were analyzed separately, and since there were not differences among the impact categories and indices in different sites, the average for the results of the three sites are being presented. Results show that decreased insecticides application in transgenic cultivars lowers the need for labor, machineries, and fuel, thereby contributing to reduction in use of energy and greenhouse gases emission from construction, transportation and application of inputs during cultivation. Furthermore, most investigated impact categories were obtained high for Tarom Molaii and Khazar and less for three transgenic lines. In addition, the most important categories were non-renewable energy, global warming, aquatic eutrophication, aquatic acidification, terrestrial acid/nutri, land occupation, terrestrial ecotoxicity, ozone layer depletion, ionizing radiation, respiratory inorganics, respiratory organics, cumulative energy demand, ecological footprint, greenhouse gas protocol, water footprint, carcinogens and non-carcinogens. Therefore, according to the findings of this research, it was observed that the emission amount of environmental pollutants has a positive correlation with the consumption of inputs and field management practices. •The lowest amount of insecticides and other non-renewable inputs was observed in transgenic rice cultivars.•Conventional cultivars exhibited the maximum production of Global Warming Potential and environmental impacts.•En