Insect-resistant biotech rice: Safety, environmental impact and the potentials for developing countries

Insect-resistant biotech rice: Safety, environmental impact and the potentials for developing countries

 Behzad Ghareyazie

Executive Director of Iran Biotechnology Information Center (IRBIC), President, Biosafety Society of Iran and Head, Modern Technologies Division, Center for Strategic Research, Tehran, Iran (ghreyazie@yahoo.com)

More than 134 million hectares of agricultural land have been devoted for the production of genetically modified (GM) crops, more widely recognized as ”biotechnology crops”. Large scale production of these crops dates back to the years 1995-1996 when China pioneered the commercialization of biotechnology crops at limited area. At the end of the year 2008, more than 14 million farmers in 25 different countries -both developing and industrial countries- benefited from biotech crops of which over 90% were small and resource-poor farmers from developing countries. Currently more than 12 different biotech crops are being grown and consumed directly or indirectly by human being. Of these crops 8 crops are being included in human diet directly. These include Soybean, Maize, Canola, Squash, Papaya, Sugar beet, Tomato and Sweet Pepper. Biotech rice is in the market at limited quantities in Iran and China since 2004. More edible crops are expected in the food basket of people living in developing countries soon. In particular, with the biosafety approval of biotech rice in China, full commercialization of this staple food for the developing world is expected within the next couple of years. Biotech eggplant is also expected to be commercialized in Bangladesh, Philippines, Egypt and other developing countries in near future. Iran has decided to grow more than 0.5% of the global area of GM crops in the country. This decision indicates the government’s positive attitude towards agricultural biotechnology including the deliberate release of LMOs into the environment. In the year 2004 coinciding with the international year of rice, Iranian government officially released an insect resistant rice line as the country’s first transgenic crop plant. This transgenic rice (line # 827; cultivar Tarom Molaii); containing a synthetic cry1Ab gene under the control of a green tissue specific PEP-carboxylase promoter, was developed in collaboration with the International Rice Research Institute. Biosafety studies and risk assessment conducted prior to the environmental release of this plant included the comprehensive molecular characterization of the transgenic plant, establishment of substantial equivalence of the GM rice with its parental conventional cultivar, nutritional and biochemical compositional analysis, animal feeding trials, five years of field trials to study the insect resistance and yield at field condition, insect bioassays on four lepidopteran insect pests (Chilo suppressalis, Scirpophaga incertulas, Cnaphalocrocis medinalis and Naranga aenescens), and environmental studies. Several studies were conducted to address the environmental concerns related to the release of this Bt rice. These studies included the assessment of the risk of gene flow and generation of “super weeds” in Iran environment, the possibility of generation of target insect resistance to the introduced protein, assessments of the effects on soil micro organisms, and the effect of GM rice on non-target organisms. Results indicated 1) the stability of transgene and its expression over more than 16 generations, 2) its efficiency as a “high dose” plant in causing 100% mortality on the tested lepidopteran insects over these generations; 3) the absence of Cry1Ab protein from root, pollen and any tissue other than green tissue and hence no negative effects on soil micro-organisms and pollinators; 4) low possibility of gene flow, because of the absence of wild rice of Oryza genus from the Iran environment, and 5) no adverse effects on non-target organisms in particular Andrallus spinidens a predator of Naranga enescense and on Trichogramma brassicae a parasitoid of Chilo suppressalis eggs since no live larvae was found to lay eggs after the 1st and 2nd instar larvae fed on transgenic rice. Over all, this study indicates the absence of threat of this Bt rice on the rice growing environment in Iran, in particular on non-target organisms beyond the effect of pest population reduction caused by the current pest control measures. Benefits of Bt rice in Iran including the reduced application of chemical pesticides will be discussed. Impact and potentials of commercialization of biotech rice for developing countries will also be discussed. Key words: GM Rice, Bt, Non-target organisms, Trichogramma brassicae, Andrallus spinidens, Environment, Biosafety, Key words: Food Safety, Modern Biotechnology, Risk Assessment