Efficacy of a bioethanol-methanol mixture for trapping coffee berry borer in arabica coffee plantations in Indonesia

The coffee berry borer (CBB), a primary pest in Indonesia, causes significant damage to coffee fruits and beans, necessitating effective control measures. This study evaluated the efficacy of a synthetic bioethanol-methanol mixture trap for capturing beetles and mitigating their impact. The experiment was conducted in two plots: Plot A, with a Leucaena leucocephala shade density of 19.5%, and Plot B, with a shade density of 13.5%. The attractant mixture used in the traps was prepared in a 1:2 ratio of bioethanol to methanol. Attractant traps were hung on coffee trees at a height of 1.2 to 1.5 meters above the ground, and beetle populations were collected weekly over a nine-week period. Damage to coffee fruits and seeds was assessed in the first, fourth, and eighth weeks. The extent of seed damage was categorized into two groups: ≤50% damage and 50% damage. Plot A, with denser shade, exhibited a significantly higher beetle capture rate of 83.26%, compared to 16.74% in Plot B. Beetle population dynamics fluctuated, peaking during the sixth week of trapping and declining thereafter until the ninth week. The higher shade density and denser coffee canopy in Plot A were associated with an increased beetle population. The use of the bioethanol-methanol attractant traps significantly reduced seed damage in both damage categories (≤50% and 50%). The results demonstrate that the bioethanol-methanol mixture is an effective tool for monitoring and controlling CBB populations, thereby minimizing fruit and seed damage.