Chemical control of apple leafroller (Bonagota cranaodes Meyrick) in apple orchards

Abstract

Apple leafroller, Bonagota cranaodes Meyrick (Lepidoptera: Tortricidae), is one of the major apple pests in Southern Brazil. Laboratory and field experiments were conducted with chlorpyriphos-ethyl (Lorsban 480 CE - 72 g of a.i./100 L), methidathion (Supracid 400 - 60 g of a.i./100 L), phosmet (Imidan 50 PM - 100 g of a.i./100 L), trichlorphon (Dipterex 500 - 150 g of a.i./100 L), tebufenozide (Mimic 240 SC - 21.6 g of a.i./100 L), fenitrothion (Sumithion 500 CE - 75 g of a.i./100 L) and carbaryl (Sevin 850 PM - 153 g of a.i./100 L) to control the pest in apple orchards. In laboratory, all insecticides caused 100% of mortality on first-instars larvae while fourth and fifth instar larvae were satisfactorily controlled only using chlorpyriphos-ethyl, tebufenozide and trichlorphon. Chlorpyriphos-ethyl application after peaks of B. cranaodes males capture in pheromone traps resulted in less than 1% of fruit damage at harvest, while tebufenozide resulted in 4.6% compared to 9.8% in a non-treated area.