ABSTRACT

In 1991, large populations of the silverleaf whitefly, (SLW), Bemisia argentifolia Perring and Bellows, were reduced 38% to 53% following applications of amitraz and buprofezin to cotton in the Lower Rio Grande Valley (LRGV) of TX. Yields of seed cotton in treated plots were significantly greater than the yields from untreated cotton following seven and four applications of amitraz and buprofezin, respectively. There were no significant differences in percentage reducing sugar and stickiness of the lint caused by adult, larvae and pupae feeding of the whitefly in treated and untreated cotton. Dead and dead + moribund whitefly adults were bioassayed with amitraz and the LC50 was 1,703.6 and 234 µg/vial. Most of the adults were moribund after three h.