Biologia reprodutiva de Solanum lycocarpum (Solanaceae): relação recíproca com abelhas polinizadoras, formigas dispersoras de sementes e drosophilideos hospedeiros de frutos

Abstract

Pollination is one of the key processes in maintaining the diversity, abundance and activities of organisms. Thus, studies involving pollinator mechanisms, sexual and reproductive systems, and seed dispersal provide essential information for the understanding of plant-animal relationships. Taking into account this information the objectives of this work were to study extensively the reproductive biology of Solanum lycocarpum, as well as to analyze the floral morphology of the species; the interaction of bees with flowers; to test the effectiveness of different pollinator species on fruit formation; the influence of abiotic factors on the flight activity of visiting bees, to verify the role of ants of the species Atta laevigata in the dispersion of their seeds, the relation of drosofilids with the fruits of this species and to evaluate the role of S. lycocarpum as a resource for the maintenance of bees in agricultural crops, by the qualitative phenological study of a population. The Bees of species Centris scopipes and Epicharis flava were the ones that most contributed to the reproductive success of S. lycocarpum since, respectively, 90% and 82.5% of the flowers visited once by them resulted in fruit. It was verified that S. lycocarpum is autoincompatible and requires the bees visitors to carry out the pollination, since it reproduces only by xenogamy. 401 aggressive encounters were recorded, contemplating the different agonistic interactions. These interactions were observed only among the species O. flavescens, E. fulvofasciata, Augochlora sp and Augochloropsis sp. It is believed that the possible reduction in the availability of resources in the area, caused by deforestation of the forest fragment, may have contributed to the intensification of competition and conflicts among bees. The majority of bees' forages were not significantly influenced by the environmental factors evaluated. Therefore, it is suggested that the reduction in the frequency of most bees foraging was not significantly influenced by the environmental factors evaluated. Therefore, it is suggested that the reduction in the frequency of forages would also be related to the reduction of the supply of pollen in the flowers of S. lycocarpum, depending on the intensity of the activities in their search in the morning, developed by the bees. Atta laevigata acted primarily as predators, with few seeds discarded, but their actions may interfere in the regeneration of native vegetation, presenting a significant role in the removal of S. lycocarpum seeds. The population of S. lycocarpum presented a continuous and quantitatively uniform flowering pattern. This pattern of flowering allows to consider the species as an excellent source of resource for the guild of pollinating bees. The fruits of this species are an important host for drosophilidae, and the species found, even though considered exotic, represent a relevant record for the transition region of Cerrado-Mata Atlântica, for the State of Mato Grosso do Sul State.