Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades.

More than 70% of world’s crops benefit from biotic pollination, and bees are their main pollinators. Despite the fact that some of these insects have been broadly studied, understanding the interactions between plant crops and their pollinators with a local scale approach is necessary when aiming to apply proper protective and management measures to pollinators and their respective crops. In this context, we analyzed the pollination status of open-field tomato crops (Solanum lycopersicum L.), regarding fruit-set, visitation rate and the quality of fruits. We recorded the formation of fruits through spontaneous self-pollination and open-pollination, and the occurrence of pollinators in 24 areas of open-field tomato crops. We performed experiments of apomixis, spontaneous self-pollination, manual cross pollination and supplemental cross pollination (simulating the pollinator behavior) in a greenhouse. The fruit quality was evaluated according to circumference, weight, volume and number of seeds. Higher production of fruits after open-pollination compared to spontaneous self-pollination indicates the importance of pollinators to increment productivity of S. lycopersicum in the study area. The circumference and the number of seeds from tomatoes of the greenhouse plantation did not differ between spontaneous self-pollination and the manual cross pollination. In the open-field crops the number of seeds was higher for fruits resulting from open-pollination. Our results indicate that the importance of bees is mainly related to the increase in fruit production, thus incrementing the productivity of tomato crops.production, thus incrementing the productivity of tomato crops.

Studies on bee-plant interactions are relevant to the understanding of temporal patterns in neotropical communities. In isolated habitats such as inselbergs little is yet known about the temporal dynamics in the availability of fl oral resources and interacting bee. In the present study, the objective is to verify the eff ect of seasonality on the bee-plant interaction in an Atlantic Forest inselberg in southeastern Brazil. The bees were sampled monthly in the dry (April/2008-September/2008) and wet seasons (October/2008-March/2009) using an entomological net. A total of 322 bees of 33 species were captured on fl owers of 34 species of plants during the year. Bees richness was similar between seasons (22 species in the wet season and 21 in the dry season), but abundance was higher in the wet season (60% of individuals) and higher diversity occurred in the dry season. Augochloropsis sp1 were the most abundant species and visited the largest number of plant species at each season. In the interaction network, plants with the highest degree were distinct between the seasons. The number of possible interactions was higher in the dry season compared to the wet season and connectance was similar; nestedness however varied between the seasons. The composition of plant and bees species was distinct between the seasons, as well as the interactions between them, mainly due to the alteration in the composition of the plant species and the change in the choice of the bees for the floral resources between the seasons.

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The Brazilian Atlantic Forest is one of the most endangered biodiversity hotspots in the world and restinga ecosystems are exposed to intense degradation. The restoration of these ecosystems is challenging as there is a lack of understanding, among other aspects, of how plants interact with pollinators. Ecological networks are useful for assessing restoration outcomes as they provide data on the reestablishment of interactions. Here, we evaluated the restoration success of pollination interactions in a restinga in Brazil, by comparing structure, complexity, and robustness of plant–flower visitor networks in newly planted sites (restoration) with target reference sites (control). In the restoration area, more species and interactions were recorded (120 insect species, 25 plant species, and 1,361 interactions) compared to the control area (74, 19, and 471, respectively), mainly due to the high abundance of common insect species. The majority of the interactions in restoration sites (81.1%) occurred with naturally arriving pioneers (68% of plant species visited). While network robustness was significantly higher in restoration sites, as a result of a high number of generalist species, interaction evenness was significantly lower, indicating less uniformity in interaction frequencies compared to control sites. Interaction turnover was high, driven by differences in the composition of plants and insects between sites. Our results demonstrate that pollinating insects do reestablish interactions with herbaceous species, enabling their interaction with later flowering target plants in the most advanced stages of restoration. These results should be taken into consideration when proposing measures to attract and retain pollinators in areas under restoration.