Control of Mexican Bean Beetle in Soybeans with Systemic Insecticides, 1976

Soybeans were planted May 28'76 with a conventional 4-row unit planter equipped with granular insecticide applicators. The insecticides were placed in a 4-inch band over the seed furrow, behind the planter shoe and in front of the press wheel. Two drag chains were attached behind the press wheel of each planter. Plots consisted of 16 rows (12 rows soybeans and 4 rows snap beans), 175 ft long with 30 in between rows, arranged in a randomized complete block design with 4 replications. Every 4th row was planted with Early Gallatin snap beans to encourage an infestation of Mexican bean beetle. No insecticide was applied to the snap beans. Soil was classified as a Bertie silt loam and the soil temp at the time of treatment was 72°F at the 4 in depth. At late pod-fill, 20 plants were selected at random following an “x” pattern in each plot. Each plant was rated visually to the nearest 10% defoliation. Yield data were taken from 2 rows,16 ft long, in the center of each plot. Yields were adjusted to 13% moisture and reported in bu/A. Rainfall was below normal except for the period during pod formation.