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Palm wine alcohol extract of senesced banana leaf material, Musa spp., was tested for its efficacy in open field trapping of the banana weevil, Cosmopolites sordidus in Ghana from June to August 2015. Modified pitfall and bottle traps were baited with either individual treatments, that is palm alcohol extract, C. sordidus aggregation pheromone or pseudostem or with combinations of extract plus aggregation pheromone or extract plus pseudostem. The combination of extract plus aggregation pheromone was able to lure more weevils into traps compared with the respective individual lures. There was a 2.1‐fold increase in mean catch per week when the palm alcohol extract was used in combination with pheromone compared with using pheromone alone, and a corresponding 2.6‐fold increase when the extract was used with pseudostem in traps. There was no statistically significant interaction between the palm alcohol extract (presence or absence) and treatment (pheromone or pseudostem), but the best combination for maximal catches of adult banana weevils was a combination of palm alcohol extract with aggregation pheromone. Management of banana weevils with attractive banana leaf extract has important practical applications in parts of the world where other management options are too expensive or commercial treatments are in short supply, but where leaf material is cheap and readily available for local use by smallholder farmers.

BACKGROUND: The banana weevil, Cosmopolites sordidus, has been frequently cited as the most challenging constraint to banana and plantain production, particularly in small-scale (smallholder) farming. For the development of a new, low-cost weevil management technology based on attractive host plant material, we previously identified (2R,5S)-theaspirane as the active component of attractive senesced banana leaves. In this new study, we used behavioural (olfactometer) bioassays with adult weevils to compare the attractiveness of four different developmental stages of banana leaves, ie. unfolding (pale green), matured green (deep green), matured yellowing and senesced, to determine which leaf developmental stage would be most appropriate for use in weevil management. We also investigated the attractiveness of senesced leaf extracts prepared using different solvents to determine which solvent would be most appropriate for local production of leaf extracts. Coupled gas chromatography-electroantennography (GC-EAG) was then used with adult weevils to confirm the presence of (2R,5S)-theaspirane in attractive leaf extracts. RESULTS: Of the leaf materials tested, only the odour of senesced leaf material was significantly attractive to adult weevils (P