Effectiveness of Aqueous Coffee Extract and Caffeine in Controlling Phytophagous Heteropteran Species

Heteroptera species are a growing problem in the cultivation of horticultural crops, and intensive chemical control of these pests is not sustainable. Therefore, natural products are used in sustainable pest management. We investigated the potential of aqueous coffee and caffeine extracts in the control of three heteropteran species Nezara viridula (L.), Halyomorpha halys (Stål), and Corythucha ciliata (Say). The Soxhlet extraction method was used to prepare the aqueous coffee extracts. Contact efficacy was evaluated by spraying the pests with the aqueous extract of coffee and the aqueous solution of pure caffeine. Significant efficacy of coffee and caffeine standard was found for control of adult H. halys (97% coffee ; 83% caffeine) and adult C. ciliata (47% coffee ; 70% caffeine). Low efficacy was observed for control of N. viridula nymphs (33% coffee ; 28% caffeine), while no insecticidal efficacy was observed for adult N. viridula. There was no statistically significant difference in efficacy between coffee extract and caffeine standard, suggesting that these caffeine levels are sufficient for pest control, while the influence of other various compounds in coffee extract (e.g., polyphenols) could not be detected. This study opens a perspective for the production of natural plant extracts using only water as the extraction medium for pest control.