Published online by Cambridge University Press: 12 June 2017
The 14C-AC 263,222 was foliar applied to common cocklebur, johnsongrass, peanut, sicklepod, and soybean in order to study translocation and metabolism characteristics in each species. Differential absorption of 14C-AC 263,222 between species was evident 4 h after application. At 48 h after application, sicklepod and peanut absorbed more 14C-AC 263,222 than johnsongrass, common cocklebur, or soybean. Translocation of 14C-AC 263,222 and its metabolites out of the treated leaves increased with time for all species. The 14C-AC 263,222 and its metabolites appear to be both xylem- and phloem-mobile based on patterns of movement. Absorption and translocation differences occurred between species; however, they did not appear to explain differential species response. Metabolism of 14C-AC 263,222 differed greatly among species. Common cocklebur metabolized less 14C-AC 263,222 than any other species 96 h after application. Johnsongrass and sicklepod metabolized 24 and 28% of the 14C-AC 263,222, respectively, 96 h after application. Peanut and soybean metabolized 76 and 62%, respectively, of the 14C-AC 263,222 96 h after treatment. The half-life of 14C-AC 263,222 was 1.1, 2.5, 7.7, 11.6, and 34.5 d in peanut, soybean, sicklepod, johnsongrass, and common cocklebur, respectively. Differential tolerance of species appears to be directly related to the half-life of AC 263,222 in the plant.