Location: Crop Production Systems ResearchTitle: Role of herbicide-resistant crops in integrated weed management
|JHA, PRASHANT - Montana State University|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 4/25/2017
Publication Date: 1/3/2018
Citation: Jha, P., Reddy, K.N. The role of herbicide-resistant crops in integrated weed management, pp. 1-10. In Zimdahl, R.L. (ed.) Integrated Weed Management for Sustainable Agriculture, Burleigh Dodds Science Publishing, Cambridge, UK, 2018.
Technical Abstract: Chemical weed control began with the use of 2,4-D in the mid-1940s. Since then, a wide array of herbicides has been commercialized and that has greatly contributed to increased crop yields. With the introduction of several new, more specific and more effective herbicides, the cost of weed control with herbicides decreased relative to other control practices (labor, fuel, and machinery). These benefits of lower production costs, higher crop yields and quality, and increased profit margins for farmers resulted in over-dependence on herbicides in weed management. Use of the same herbicide year after year has led to evolution of herbicide-resistant (HR) weeds. HR transgenic crops were commercialized in the mid-1990s and were rapidly adopted by the farmers as they provided effective and economical weed management options. Over-reliance on HR technology also resulted in evolution of HR weeds. The severity of HR weeds led to development and commercialization of several multiple HR (stacked–trait) crops as new tools for managing weeds that are difficult-to-control or resistant to glyphosate and other herbicides. With the future use of HR crop technology, shifts in weed populations related to ecological adaptation, natural tolerance, or evolved resistance, will continue to pose an economic threat to production agriculture, unless “diversification” is adopted. Lessons need to be learnt and integrated weed management (IWM) programs need to be implemented to maintain sustainability of GR and other HR crop technologies. This chapter provides an outlook on major HR crops (commercialized or under development), their benefits and pitfalls, and outlines a direction forward for growers to manage weeds, regardless of herbicide resistance.