THE INFLUENCE OF TERBUFOS ON PRIMISULFURON ABSORPTION AND FATE IN CORN (ZEA-MAYS)

Terbufos and primisulfuron interactions were evaluated under growth ch amber conditions using a sand culture system. Terbufos was applied to transplanted corn seedlings, followed in 5 d by foliar applications of primisulfuron plus nonionic surfactant. Primisulfuron and terbufos al one did not cause corn injury; however, shoot dry weight and shoot len gth were reduced 28 and 36% in terbufos treatments 96 h after primisul furon application. Primisulfuron absorption and translocation were not affected by terbufos, but the half-life of primisulfuron increased fr om 2 to 3.5 h in terbufos treatments. Terbufos did not affect primisul furon metabolite profiles. The basis for increased primisulfuron phyto toxicity in terbufos treatments appeared to result from reduced primis ulfuron metabolism.