Greenhouse studies were conducted to evaluate halosulfuron tolerance of several squash and cucumber cultivars commonly grown in Georgia. There was an inverse linear relationship between squash plant biomass and rate of halosulfuron (r2 = 0.70 to 0.92). With the exception of ‘Supersett’, the slopes from regression of all squash cultivars were equivalent. The estimated amount of halosulfuron required to reduce growth by 20%, based on regression, ranged from 8.2 to 45 g ai/ha (for Supersett and ‘Dixie’, respectively). Squash plant height was also reduced by halosulfuron, though plants began to recover from the injury by the end of the study. There was no effect of halosulfuron rate on cucumber plant biomass or height. Cucumber cultivars appeared to be more tolerant to halosulfuron than did squash cultivars.
Nomenclature: Halosulfuron; cucumber, Cucumis sativus L.; squash, Cucurbita pepo L.
Additional index words: Cyperus esculentus, Cyperus rotundus, methyl bromide alternatives, MON 12037, purple nutsedge, vegetable weed management, yellow nutsedge.
Abbreviations: DAP, days after planting; GR20, herbicide rate required to reduce crop growth 20%; POST, postemergence; PRE, preemergence; PRE–POST, half rate PRE followed by half rate POST.