ISSN 2756-3839
International Journal of Nematology and Entomology ISSN 2756-3839 Vol. 9 (6), pp. 001-005, June, 2022. © International Scholars Journals
Review
Gene pyramiding as a Bt resistance management strategy: How sustainable is this strategy?
Manyangarirwa, W.1*, Turnbull, M.1, McCutcheon, G.S.2, and Smith, J.P.3
1Department of Entomology, Soils and Plant Sciences, Clemson University, Clemson, SC 29634-0315, USA.
2Coastal Research and Education Center, Clemson University, 2700 Savannah Highway, Charleston, SC 29414-5329, USA.
3Edisto Research and Education Center, Clemson University, 64 Research Road, Blackville, SC 29817, USA.
Accepted 24 May, 2022
Abstract
Reports on the emergence of insect resistance to Bacillus thuringiensis delta endotoxins have raised doubts on the sustainability of Bt-toxin based pest management technologies. Corporate industry has responded to this challenge with innovations that include gene pyramiding among others. Pyramiding entails stacking multiple genes leading to the simultaneous expression of more than one toxin in a transgenic variety. Questions have been raised on the sustainability of gene pyramiding since the use of insecticide mixtures has shown that cross resistance and/or multiple resistance can render such strategies to be less effective in the long term. Current theoretical and practical evidence in insect population genetics suggest that gene pyramiding cannot be sustained as a resistance management strategy per se. Pyramiding is useful as a strategy to broaden the range of insect pests controlled in each transgenic variety, and it still has to be deployed in tandem with Bt resistance management strategies such as crop refugia, biological pest control, temporal and spatial crop rotations among others.
Key words: Gene pyramiding, Bacillus thuringiensis, resistance management.