2022 article

HPPD-resistant cotton response to isoxaflutole applied preemergence and postemergence

Joyner, J. D., Cahoon, C. W., Everman, W. J., Collins, G. D., Taylor, Z. R., & Blythe, A. C. (2022, February 10). WEED TECHNOLOGY.

author keywords: cotton tolerance; cotton injury; acetochlor; dimethenamid-P; diuron; fluometuron; fluridone; fomesafen; glufosinate; glyphosate; isoxaflutole; pendimethalin; pyrithiobac; cotton; Gossypium hirsutum L
Source: Web Of Science
Added: May 2, 2022

Abstract Studies were conducted in 2019 and 2020 at Lewiston, NC to determine the crop response of 4-hydroxyphenylpyrivate dioxygenase (HPPD)-resistant cotton to IFT and other cotton herbicides as part of a cotton weed management program, which included PRE, early-POST (EPOST), and mid-POST (MPOST) herbicides. Isoxaflutole (IFT) was applied PRE at 105 g ha -1 alone and in various combinations with acetochlor, diuron, fluometuron, fluometuron, fluridone, fomesafen, pendimethalin, and pyrithiobac. Early POST treatments included IFT at 53 or 105 g ha -1 alone or in combination with glyphosate or glufosinate, or dimethenamid- P + glufosinate. Glyphosate + glufosinate was applied mid-postemergenceT to all treatments except the nontreated control. Cotton injury from IFT PRE was minimal (0 to 3%). Injury following EPOST dimethenamid- P + glufosinate ranged 3 to 5% and 6 to 9% in 2019 and 2020, respectively. In both years, injury from IFT PRE followed by IFT EPOST never exceeded injury from IFT PRE followed by dimethenamid- P + glufosinate. Isoxaflutole fb IFT EPOST at 105 g ha -1 resulted in 0 to 2% cotton injury, indicating IFT can be applied PRE or EPOST with minimal risk to cotton. Late-season cotton height and cotton lint yield were not affected by any herbicide treatment. The experimental HPPD-resistant cotton cultivar was minimally injured by IFT PRE and EPOST, tolerated standard cotton herbicides, and yield loss was not observed. Given these results, HPPD-resistant cotton and IFT may be integrated into cotton weed management systems with minimal risk for cotton injury and provide an additional effective mechanism of action for managing troublesome weeds in cotton.