Pollination of Byrsonima coccolobifolia: short-distance isolation and possible causes for low fruit production

Byrsonima coccolobifolia is a tropical plant from the Malpighiaceae family, distributed in the neotropical savanna fields and pollinated by bees known as "collecting-oil bees". In this study, conducted in a Cerrado area located on a farm in the city of Silvânia, GO, the following hypothesis was tested: the greater the isolation degree of a plant, the lower its fruit production due to access difficulties for pollinators. Using a linear regression analysis, it was possible to relate the fruiting rate with the degree of isolation of each B. coccolobifolia individual and consequently it was found that the isolation had no influence on the pollination rate, an unexpected event that can be explained by the distance amongst individuals not being large enough to limit the movement of pollinators, or because cross-pollination was not the predominant form of reproduction, since the rate of cross-pollination was similar to self-pollination. It was also found that the proportion of fruits produced was lower than expected, a factor which may also have influenced the results.