Invisible Architecture of Tephritids (Diptera): A Chemically Mediated Exploration of Ecological Structure in Tropical Orchards of Northern Cameroon

Abstract

Understanding the ecology of tephritid communities is essential for developing sustainable pest management strategies in tropical fruit-based agroecosystems. This study assessed relative abundance and the efficacy of four male-specific semiochemical lures (methyl eugenol (ME), cue-lure (CU), terpinyl acetate (TA), and trimedlure (TR)), across two agroecological zones (AEZs) in Cameroon: the Sudano-Sahelian savannah (AEZ 1) and the High Guinea savannah (AEZ 2). Nine tephritid species were recorded, including two previously unreported in these AEZs ( Ceratitis punctata and C. fasciventris ). Despite a shared species pool, community structure differed significantly between AEZs. In AEZ 2, Bactrocera dorsalis accounted for over 90% of captures, reflecting its invasive dominance. This was amplified by the high specificity of ME, which almost exclusively attracted B. dorsalis . Conversely, AEZ 1 supported a more balanced assemblage dominated by B. dorsalis , Zeugodacus cucurbitae , and Ceratitis cosyra , particularly in dry AEZ rich in cucurbit crops. Thus, CU was effective in capturing cucurbit-associated species ( Z. cucurbitae , Dacus spp.), while TR and TA attracted a broader range of Ceratitis species. These findings highlight the value of multi-lure trap systems in accurately revealing tephritid community composition and support the need for agroecologically tailored Integrated Pest Management (IPM). Promoting the use of semiochemical surveillance in smallholder systems will require institutional support to offset lure costs. Such strategies can improve early detection and targeted control of key tephritid pests, ultimately enhancing crop protection in vulnerable agricultural landscapes of various sub-Saharan Africa countries.