Biosafety risk assessment approaches for insect-resistant genetically modified crops

Abstract

Background: Environmental risk assessment (ERA) is imperative for commercial release of insect resistant, genetically modified crops (IR-GMCs).An insect specific, spider venom peptideω-HXTX-Hv1a (Hvt) was successfully expressed in cotton plants. The cotton plants producing Hvt protein have demonstrated resistance against economically important insect pest species. The study was performed to assess the effects of Hvt producing cotton plants on Honey bees (Apis mellifera). Methods: Three approaches were used to evaluate the effects of Hvt protein on adults of honeybees; whole plant assays in flight cages, in vitro assays with pollen of Hvt-cotton, and assays with elevated levels of purified Hvt protein. Pollens of Bt cotton or purified Bt proteins were used as control. Results: The field experiments did not yield any meaningful data due to high rate of mortality in all treatments including the control. However, the laboratory experiments provided conclusive results in which Hvt, purified or in pollens, did not affect the survival or longevity of the bees compared to the control. During the course of study we were able to compare the quality, effectiveness and economics of different experiments. Conclusions: We conclude that Hvt either purified or produced in cotton plants do not affect the survival or longevity of honey bees. We are also of the view that starting at laboratory level assays not only gives meaningful data but also saves a lot of time and money that can be spent on other important questions regarding safety of a particular transgenic crop. Hence, a purpose-based, tiered approach could be the best choice for pre-release ERA of IR-GMCs.

Keywords

• Biosafety
• GMCs
• ω- HXTX-Hv1a
• Apis mellifera
• Biotechnology