​Herbicide Resistance Status and Seedbank Persistence of Palmer amaranth (Amaranthus palmeri) and Waterhemp (A. tuberculatus) in Texas

October 2018 | 12 min., 28 sec.
by Muthu Bagavathiannan and Peter Dotray
Texas A&M AgriLife Research and Extension and Texas Tech University


​Weed resistance is a growing issue in Texas, particularly in the two major pigweed species: Palmer amaranth and waterhemp. However, knowledge has been limited on the current level of resistance in these species as well as their persistence in the soil seedbank. This presentation will help consultants, growers, and other practitioners in Texas to understand more about the distribution of resistance in these weed species to some of the historically important herbicides such as glyphosate and atrazine, as well as the longevity of pigweed seeds in the soil seedbank after burial. The information provided in the presentation will help create awareness among the practitioners on the significance of herbicide-resistant weeds in Texas and the importance of being proactive in protecting available herbicide options. The seedbank longevity data informs practical management of these species. At the end of the presentation, the practitioners will develop an understanding of how to deplete the soil seedbank of Palmer amaranth and waterhemp.​

About the Presenter

Muthu Bagavathiannan ​Muthu Bagavathiannan received his PhD in Weed Ecology at the University of Manitoba in 2010. After a postdoctoral research training on the evolutionary dynamics of herbicide res​istance in weeds at the University of Arkansas, he joined the Department of Soil and Crop Sciences, Texas A&M University as an Assistant Professor of Weed Science in 2014. His current research focuses on weed ecology, evolution, and integrated management. A notable research area is weed seedbank ecology and management to minimize long-term weed persistence. His research works on herbicide resistance modeling has allowed the development of best management practices (BMPs). He is also involved in the development of decision-support tools to help disseminate sound BMPs. Dr. Bagavathiannan collaborates widely with eminent research groups locally, nationally and internationally.

​​Peter Dotray​Peter Dotray is a weed scientist with a joint appointment at Texas Tech University, Texas A&M AgriLife Extension Service, and Texas A&M AgriLife Research in Lubbock, Texas. Dr. Dotray teaches undergraduate and graduate level courses in weed science at Texas Tech University, serves as an Extension Weed Specialist in the Texas Southern High Plains (a region where over 3 million acres of cotton is grown), and conducts research to help development effective and sustainable weed management systems in crops grown in the region.

Contact Information:
Email: muthu@tamu.edu, peter.dotray@ttu.edu


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