Estrutura genética e sociogenética das populações e ninhos de Euglossini (Hymenoptera: Apidae) determinadas por meio de microssatélites

Abstract

Euglossine bees are important pollinators of many Neotropical plant species, particularly orchids which could present a species-specific bee-flower relationship, essential to the reproductive success of these plants. Orchids produce chemical compounds to attract males of Euglossine bees (the effective pollinators of the orchids), and these compounds were isolated and are being used to study the biology of the euglossine males. Allozymes markers, although their low polymorphism content, were widely applied in population analyses. In order to provide a powerful tool to be applied to nest and population genetics research, primers flanking microsatellite loci were developed for Eulaema nigrita and Euglossa cordata (13 loci each). The use of these markers in 483 euglossine males of Euglossa, Eufriesea, Eulaema and Exaerete species, sampled in several Brazilian biomes and areas, evidenced the presence of only two diploid males, one in Euglossa annectans and other in Euglossa mandibularis. These findings support the hypothesis that diploid males (usually unviable or sterile individuals) occur in low frequencies in Brazilian Euglossine bee populations, a fact that is according to previous studies using allozymes. The application of these markers to nest structure analyses revealed nest sharing among unrelated females of Eulaema nigrita (eight nests). For Euglossa cordata and Euglossa townsendi nests (11 and seven nests, respectively), analysis demonstrated that monogamy (one female mated with a single male) is the rule, although nest sharing among unrelated females could also occur in E. townsendi. These results give a new focus on the research about population genetics and nest sociogenetic structure of Euglossine bees, opening new insights on the Euglossini biology and genetics.