Pollination efficiency of Apis mellifera(Hymenoptera: Apidae) on Lantana camara(Verbenaceae) flowers at Dang (Ngaoundéré, Cameroon)

Abstract

To evaluate the impact of Apis mellifera on Lantana camara production, foraging and pollination activities of this bee were studied at Dang. In August 2016 and 2017, 540 floral bunches with flowers in bud were labeled on 25 plants to constitute four treatments : 120 bunches left unprotected, 120 bunches protected from insects; 200 bunches covered, then uncovered, visited exclusively by A. mellifera and rebagged; 100 bunches protected, then uncovered and rebagged, without insect or any other organism visits. The foraging behavior of A. mellifera, on flowers its pollination efficiency, the fruiting rate, the percentage of mature fruit and the percentage of normal (well developed) fruits were evaluated. Results show that among 13 insect species recorded on L. camara flowers after two seasons of observations, A. mellifera was the most represented with 40.38% of 317 visits. This bee exclusively harvested pollen, almost throughout the day. The fruiting rate, the percentage of mature fruits and the percentage of normal fruits of treatments with unprotected floral bunches were significantly higher than those of treatments with floral bunches protected from insects. Through its pollination efficiency, A. mellifera increased the fruiting rate, the percentage of mature fruits and the percentage of normal fruits by 59.95%, 28.27% and 44.12% respectively. This Verbenaceae can be cultivated to help maintain colonies of A. mellifera during the rainy season for a good production of honey and pollen as hive products.