Commercial formulations of spinosad (Tracer® 4 SC) and abamectin (Agri-Mek® 0.15 EC) mixed with 10% sucrose on a ppm ai weight:volume basis were evaluated as toxicants when fed to boll weevils (BW), Anthonomus grandis grandis Boheman, captured in pheromone traps during spring and fall, 2000. For both spinosad and abamectin, there was no significant difference in lethal concentration (LC) values between spring- and fall-captured BW of mixed sexes. The pooled 24 h LC _90s for spinosad and abamectin were 28.0 ppm (95% CLs [confidence limits] of 23.31 to 35.62) and 6.5 ppm (95% CLs of 5.37 to 8.44), respectively. When compared with 10% sucrose alone as control and relative to LC ₉₀ insecticide concentrations, abamectin significantly inhibited gustatory response of male and female BWs more than spinosad, but there were some differences in response to the same insecticide concentration due to sex. Females ingested significantly more spinosad than males at 28 and 140 ppm. Spinosad significantly reduced gustatory response for both males and females at concentrations higher than 10X LC _90. Males ingested significantly more abamectin than females at 65 ppm (10X LC _90), while females ingested significantly more abamectin than males at 650 ppm (100X LC _90). Abamectin has limited potential for use as a toxicant because although it is more toxic than spinosad, it inhibits gustatory reponse at the LC ₉₀ concentration and higher. These data indicate that spinosad does have potential for use as a toxicant mixed with a feeding stimulant and with pheromone as an attractant in an adult control system because it is toxic at relatively low concentrations and does not inhibit gustatory response even at high concentrations.