Field Efficacy Confirmation of Best Blend Ratio Option for Lures Used for Fruitfly Trapping in Cucurbit Crops Ecosystems of Sri Lanka

Abstract

Tephritid fruit flies are an important constraint to marketable fruit yields in cucurbit and tree fruit crops globally and trapping them with aggregation pheromonelures is recommended for their effective management-both by monitoring and/or by mass trapping. The present field study was taken up in Sri Lanka, on the relative efficacy of blending Cue-lure, (CL) being the recommended fruit fly attractant for melon fruit flies for synergy benefit with another attractant- Methyl Eugenal (ME), as potential synergist in cucurbit ecosystem. The replicated field study in cucurbit crops ecosystem among three locations in SriLanka during May-June 2019 showed that overall numbers of B.cucurbitae in trap catch were consistently higher (more than double) when CL was blended with ME( CL+ME) compared to CL alone, so confirming the synergy effect of blending CL. In addition, blending of CL with ME(3:1 ratio) in same lure source caused six-fold increase in trap catch of B.dorsalis species complex, which is a cost- free bonus effect with habitat- sanitation advantage. There is immense scope for collaborative R&D to gain further insight into chemical ecology of para-pheromone-based trapping systems for maximising the economic impact in trapping of the fruit flies which are economically important in cucurbit ecosystem in Srilanka and in South Asia region.