Studies were conducted during 1988-1994 to compare the effectiveness of application of various insecticides through a sprinkler irrigation system for the control of the fall armyworm, Spodoptera frugiperda (J. E. Smith), infesting corn (Zea mays L.). The treated plots were artificially infested during the whorl stage with 10 newly-hatched larvae/plant 2 d before insecticide application. The effectiveness of the insecticides were determined couting the number of live larvae/50 plants selected at random, three, 10 or 15 d after insecticide application. Chlorpyrifos (288.0 g i.a./ha) provided the most consistent control of fall armyworm larvae (82.9-98.7% effectiveness) followed by carbaryl (1105.0 g i.a./ha)(84.0%), diazinon (480.0 g i.a./ha) (83.4%), lambdacyalothrin (10.0 g i.a./ha) (81.3%), triflumuron (2.5 g i.a./ha) (79.9%) and diflubenzuron (50.0 g i.a./ha) (73.3%).
Insecta; insectigation; irrigation; Zea mays; chemical control
