Efficency of spinosad and runner in controlling the pink bollworm and their side effects on honeybees

A study was conducted to evaluate the efficiency of spinosad and methoxyfenozide, in comparison with chlorpyrifos, in controlling the pink bollworm and their side effect on honeybee workers. Data cleared that exposing 1st instar larvae of the pink bollworm to the two insecticides resulted in significant shortening in larval duration and significant increase in% larval mortality and decrease in % pupation. The LC50 were 0.028 and 203.7 ppm, while the LC90 was 0.506 and 105390 ppm for spinosad and methoxyfenozide, respectively.Chlorpyrifos induced the highest % reduction (77.44 and70.71%), in predators population, while the IGR methoxyfenozide caused the least (42.20 and 35.05%) during 2004 and 2005.Methoxyfenozide proved to be safe to honeybee workers. On the other hand, spinosad killed 100% when applied orally at 1/4 field rate and 94.1% by direct contact at the field rate of application. Chlorpyrifos was the most toxic to honeybee workers killing 100% even at 1/32 of the field rate. The LC50 of spinosad and chlorpyrifos on honeybee workers attained 6.510 and 21.617ppm by oral route, 9.927 and 12.223ppm by direct contact. Spinosad was as 29.856 and 81.216% as toxic as chlorpyrifos orally and by direct contact, respectively.