PERTANIKA JOURNAL OF TROPICAL AGRICULTURAL SCIENCE

The entomofauna and the behavioral patterns of potential pollinators were studied on female and male flowers of the oil palms Elaeis guineensis, Elaeis oleifera and oleifera x guineenis (OxG) hybrids in the Pacific coast and Amazon basin productive regions in Ecuador. Insect population studies were performed using a stratified sampling method and the determination of insect activity by monitoring insect arrivals to female flowers in anthesis. Additionally, insect pollinator pollen-transport capacity and life cycles were determined for Elaeidobius kamerunicus, Grasidius hybridus, Couturierius constrictirostris and Mystrops costaricensis. Elaeis guineensis female flowers were visited only by Elaeidobius kamerunicus, in both locations, at the Amazon basin plantation and at the Pacific coast plantation. Elaeidobius kamerunicus was the most abundant species (1,960 individuals) on E. guineensis during the dry season in Amazonia. Elaeis oleifera and OxG hybrids showed high numbers of G. hybridus (771 and 194 individuals, respectively). Couturierius constrictirostris and M. costaricensis visited the flowers in lesser numbers. The activity studies showed that E. kamerunicus had diurnal behavior, while G. hybridus was active in the morning in the Amazon region and at dusk on the Pacific coast. Elaeidobius kamerunicus was the pollinator with the highest pollen loading capacity (8,273 grains/individual). The life cycle of C. constrictirostris was the longest (41.7 days in the Amazon region and 30.3 days on the Pacific coast), followed by E. kamerunicus, with 36.7 days in Amazonia and 30.3 days on the Pacific coast.