Residual and sub-lethal effects of an attracticide formulation on Choristoneura rosaceana (Harris), Pandemis pyrusana Kearfott, and Cydia pomonella (L.) males (Lepidoptera : Tortricidae)

Abstract

A bioassay was developed to evaluate effects on Choristoneura rosaceana (Harris), Pandemis pyrusana Kearfott, and Cydia pomonella (L.), males exposed to an attracticide loaded with 6% permethrin and aged under field conditions. High levels of knock down (> 97%) at 1 h, and mortality (> 94%) at, 24 h after exposure to fresh attracticide were observed among the three species. Mortality and knock down decreased linearly as the attracticide aged and was greater than 50% even with attracticide aged 30 days. Leg autotomy was observed in all three species, being a novel response for both leafroller species. Leg autotomy reached maximum values (62.7%, C rosaceana; 41.2%, C pomonella; and 40.5%, P. pyrusana) with males exposed to fresh or attracticide aged 10 days, increasing significantly between 1 and 24 h after exposure. Leg autotomy was highly variable over time with more than 50% of males dropping at least one leg but less than 3% dropping up to 4 among tortricid species. Most autotomized legs were from the second and third pair. The zone of abscission was the junction between the trochanter and femur in all individuals. Most leg autotomized males died.