Response of quizalofop-resistant rice to sequential quizalofop applications under differential environmental conditions

Abstract Quizalofop-resistant rice allows for over-the-top applications of quizalofop, a herbicide that inhibits acetyl-coenzyme A carboxylase. However, previous reports have indicated quizalofop applied postemergence may cause significant injury to quizalofop-resistant rice. Therefore, field experiments were conducted evaluate the response cultivars across different planting dates. Under controlled conditions, effects soil moisture content, air temperature, and light intensity on sensitivity investigated. In date experiment, more than 11 percentage points was observed early-planted compared with late-planted at 5-leaf stage, higher under saturated conditions. labeled rate caused ≤16% reduction in yield regardless environment. exhibited by least 25 when maintained 90% or 100% capacity because ‘PVL01’, ‘PVL02’, ‘RTv7231 MA’ ≥42%, 30%, ≥54% injury, respectively, ≤10%, ≤5%, ≤22% 40% 50% capacity, pooled over rating timing. Greater ranging from 18% 31% grown low (600 µmol m −2 s −1 ) 5% 14% high (1,150 ). The persisted 7 28 d after stage application (DAFT), averaged temperatures (20/15 C 30/25 day/night, respectively). At DAFT, greater (by 5 21 points) cultivars; PVL01, PVL02, RTv7231 MA 33%, 9%, 58% 20/15 temperature conditions 13%, 4%, 37% day/night intensities. Overall, is likely risk if it cool, cloudy, moist