Student/presenter: Megan Mills, M.S. Student, Weed Science
Format: Oral presentation
Title: Axant™ Flex cotton response to topramezone in the Texas High Plains
Megan Mills1, Peter A. Dotray1,2, Gregory. B. Baldwin3, Scott Asher4, Adam C. Hixson4, and Bobby Rodriguez2
1Texas Tech University, Lubbock, TX
2Texas A&M AgriLife Research and Extension Service, Lubbock, TX
3BASF, Research Triangle Park, NC
4BASF, Lubbock, TX
The surge of herbicide-resistant weeds such as Palmer amaranth (Amaranthus palmeri S. Watson) is an issue across the Cotton Belt. AxantTM Flex technology developed by BASF Corporation is the first four-way herbicide tolerant trait in cotton that can tolerant glyphosate, glufosinate, dicamba, and specific p-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides including isoxaflutole. The ability to use HPPD-inhibiting herbicides would give cotton producers in the Texas High Plains an additional unique mode of action to control Palmer amaranth and other problematic weeds. A field study was conducted in 2022 at the Texas Tech University New Deal Research Farm in New Deal, Texas to evaluate AxantTM Flex cotton response to topramezone, another HPPD-inhibiting herbicide, applied alone or in tank-mix combinations when applied postemergence at a 2- to 4-leaf growth stage. Applications consisted of isoxaflutole or prometryn applied preemergence (PRE) followed by (fb) topramezone applied alone, or tank mixed with isoxaflutole, glufosinate, glyphosate, or dicamba applied early postemergence (EPOST). No EPOST treatment made to 3-leaf cotton caused greater than 3% crop response at 7 days after application. Visual crop response was ≤ 6% at 14 days after EPOST applications. At 28 days after EPOST applications, crop response did not exceed 1% across all treatments. Treatments containing isoxaflutole or prometryn PRE fb topramezone POST did not vary in crop response at 7, 14, and 28 DAA. No differences in lint yield were observed. These results support the potential use of topramezone EPOST at a 2- to 4-leaf growth stage in AxantTM Flex cotton to help manage herbicide resistant weeds.