Application of ethylene synthesis inhibitor in arabica coffee on field infestation, preference, and performance of Hypothenemus hampei

Abstract

Coffee berry borer (CBB) Hypothenemus hampei is the major pest of coffee fruits worldwide. Bioregulators have been applied in crop plants with the aim of changing their physiology and metabolism for better yield and quality of produce, but little knowledge exists on the effects on insect pests. This study evaluated application of ethylene synthesis inhibitor in arabica coffee on CBB field infestation, preference, and performance in function of application time and dose. Field experiments were conducted in Lavras, Brazil, and the effects of ethylene synthesis inhibitor Mathury™ on CBB were evaluated using five treatments: control (water); Time1 + Dose1; Time1 + Dose2; Time2 + Dose1; and Time2 + Dose2. The first and second applications were performed at 80 and 110 days after flowering, respectively, using the doses of 2 and 15 L ha−1. CBB field infestation was recorded through time as the percent bored fruits, and the colonization in the beans and degree of fruit maturation were evaluated at harvest. CBB preference and colonization were assessed in dual-choice bioassay and the performance under no-choice condition in the lab. Plants treated with the bioregulator overall presented fruits less suitable for CBB preference and performance in terms of females choice and survival in the lab, but varying effects were found between field experiments for bored fruits (%), which increased with fruit maturation. In the second field experiment, reduced larvae and pupae infestations were found in bioregulator-treated fruits. Application of ethylene synthesis inhibitor is promising to complement CBB management in sustainable coffee crops. Future research should evaluate the underlying induced-resistance mechanisms.