Field Testing Candidate Insecticides on Radish, Cabbage, and Cauliflower for Control of the Cabbage Maggot in New York State1

Abstract

New and standard insecticides were evaluated for control of Hylemya brassicae (Bouché) on radish, cabbage, and cauliflower. Insecticides were broadcast as preplanting soil treatments, placed in the seed furrow at planting, and applied as postemergence drenches on radish. Of new materials tested, Bayer 37289 (O-ethyl O-2,4,5-trichlorophenyl ethylphosphonothioate), Dasanit® (O, O-diethyl O-[p-(methyl sulfinyl) phenyl] phosphorothioate), Dyfonate® (O-ethyl S-phenyl ethylphosphonodithioate), and carbofuran gave more consistent control than diazinon, which is currently recommended for cabbage maggot control. Furrow and drench methods of application were better than broadcast treatment, judged by the levels of control achieved. Combinations of setting solutions including water, water and diazinon, water and starter, water and diazinon and starter, applied with transplants during the setting of cabbage, were compared with transplants set with no treatment. Although diazinon provided good control of maggot this control was not accompanied by a significant increase in yield at harvest. Of candidate insecticides applied as drenches to cauliflower, Dyfonate, diazinon, and Bayer 37289 achieved the most promising levels of cabbage maggot control.