Methodology to Test Control Agents and Insecticides Against the Coffee Berry Borer Hypothenemus hampei.

Abstract

Prior to recommending insecticides to treat the coffee berry borer (CBB) Hypothenemus hampei, it is valuable to know the mortality and repellency of these insecticides against adult insects or their impact on reproductive output. However, currently available methods assess adult mortality only, limiting the selection of novel insecticides with a different mode of action. In this work, different experimental methods were examined to identify the diverse effects on the CBB under laboratory conditions. For this, green coffee fruits (GFs) were collected and disinfected by immersion in sodium hypochlorite solution followed by UV light irradiation. In parallel, CBB adults from a colony were disinfected by immersion in sodium hypochlorite solution. To assess fruit protection (preinfestation), the fruits were placed in plastic boxes, and the insecticides were applied. Then, the CBB adults were released at a rate of two CBBs per GF. The GFs were left under controlled conditions to evaluate CBB infestation and survival after 1, 7, 15, and 21 days. To evaluate insecticide efficacy after CBB infestation (postinfestation), CBB adults were released to the GFs in a 2:1 ratio for 3 h at 21 °C. Infested fruits showing CBB adults with their abdomens partially exposed were selected and placed in 96-well racks, and the CBBs boring into the fruits were treated directly. After 20 days, the fruits were dissected, and the CBB biological stages inside each fruit were recorded. The GFs served as substrates that mimic natural conditions to evaluate toxic, chemical, and biological insecticides against the CBB.