Diversity and flower-visiting rates of bee species as potential pollinators of melon (Cucumis melo L.) in the Brazilian Cerrado

• Naturally occurring bees may act as pollinators of melon in the Brazilian Cerrado.
• Bees of the genus Apis, Halictus, Plebeia and Trigona visited Cucumis melo flowers.
• Bee visitation intensity was similar between male and hermaphrodite flowers.
• Bee visitation intensity correlated significantly with yield traits (fruit weight).
• Five melon cultivars showed feasibility for production in under Cerrado conditions.

Although bees are important pollinators in many ecosystems worldwide, studies on bee diversity and their contribution to pollination of commercial plants in the Brazilian Cerrado (savannah-like biome) are scarce. The Cerrado biome covers approximately 23% of Brazil and is one of the world's most important agricultural frontiers. Here, we conducted field experiments in the Brazilian Cerrado to evaluate the diversity of bees, their foraging behaviors and flower visiting periods, and their potential contribution to the performance of six melon (Cucumis melo L.) cultivars. Five bee species (Apis mellifera, Halictus sp., Plebeia sp., Trigona pallens, and T. spinipes) were recorded visiting both male and hermaphrodite flower types of all C. melo cultivars. Whereas A. mellifera showed two peaks of flower visitation (an intense first one between 8:00 a.m. and 11:00 a.m. and a second less intense one after 4:00 p.m.), all other bee species visited the C. melo flowers only in the morning, with intensities and visitation peaks similar to those of A. mellifera. All of these bees collected nectar and pollen. Our results also indicated a moderate correlation between the intensity of bee visitation and fruit weight, demonstrating that all of these bees had the potential to pollinate C. melo and to influence its productivity. Except for the cultivar ‘Hibrix’, all the other cultivars showed economic feasibility and produced fruits of marketable sizes, with an estimated yield (over 25 tons/ha) in the range registered in other Brazilian regions.