Changes in Endogenous Carotenoid Pools of Turf and Weed Species as Affected by Mesotrione and Environmental Conditions

Mesotrione, a carotenoid biosynthesis inhibiting herbicide, was evaluated for its use in turfgrass systems. Experiments were conducted to evaluate smooth crabgrass (Digitaria ischaemum) control with preemergence applications of mesotrione plus prodiamine. Experiments evaluated the influence of application timing on the efficacy of mesotrione plus prodiamine combinations and compared mesotrione plus prodiamine to current preemergence and early-postemergence herbicide treatments used for control of crabgrass. Greenhouse studies were conducted to compare the effects of foliar, soil, and soil plus foliar application of mesotrione on yellow nutsedge (Cyperus esculentus) and large crabgrass (Digitaria sanguinalis). Research was conducted in environmental growth rooms to investigate the effects of light intensity and temperature on perennial ryegrass (Lolium perenne) and large crabgrass carotenoid composition following mesotrione application.