Mark-Release-Recapture Experiments in a North Sumatra Oil Palm Plantation: Assessing the Impact of Super-Male Planting Material on Fruit Set and Elaeidobius kamerunicus population size

Yield improvement is a main issue in the oil palm industry. Several ways to achieve this goal are possible, like, for instance, improving fruit set. Here we explore a planting strategy to increase two major factors influencing pollination; i.e. (1) the number of individuals of its main pollinator, Elaeidobius kamerunicus Faust, and (2) pollen availability, by mixing oil palm planting material, usually highly feminine, with a new oil palm material, the "super-male" (SM) planting material, with a high ratio of male inflorescences. We design and study a field trial comprising extremely feminine planting material mixed with different SM densities. Using Mark-Release-Recapture experiments we estimate the average dispersal of the pollinators over three different periods of the year, from 2017 till 2022. Second, using phenological data recorded over the same period, we studied the impact of the SM planting density on the population size of the pollinators. Finally, we assess the impact over time of different SM planting densities on the fruit set, the fruit-to-bunch, and the number of trapped wild pollinators. The combination of SM material with a highly feminine planting material provides very promising results in terms of fruit set, linked with increased pollinator population and pollen availability, demonstrating its potential for application in oil palm plantations.