Ants as Potential Pollinators in Agroecological Crops

Abstract

Ant pollination is a poorly studied interaction because ants have historically been considered mainly as nectar thieves. However, a few recent studies have reported effective pollination by ants both in wild plants and crops, although their potential as pollinators is still underexplored. In this study, we address the potential role of ants as pollinators of agroecological crops in NW Patagonia. We visited 25 agroecological orchards to identify crops whose flowers were visited by ants, the ant species involved, their behaviour during floral visits, and the number of legitimate visits. Additionally, we quantified ant pollen loads and the effect of ant body secretions on pollen germination. We recorded visits from Dorymyrmex tener, D. wolffhuegeli, Brachymyrmex patagonicus, Lasiophanes picinus and Solenopsis richteri to the flowers of 10 out of 47 crops. Ants were mainly legitimate visitors to small and open flowers, and primarily nectar thieves of larger flowers, with D. tener being the most frequent species. All ant species presented pollen loads from the visited crops, and contact with ant bodies reduced but did not completely suppress pollen germination in most crops. We found that ants visit the flowers of different crops in the region, and that their potential as pollinators depends both on the crop and the ant species involved, with higher chances of effective pollination by generalist and abundant ants, and crops with small and open flowers. This study contributes to understanding the role of ants in food production, which is especially relevant in the context of increasing environmental degradation and the pollination crisis.