RESUMO
Loss and fragmentation of native vegetation negatively affect crop pollinators and productivity of several crop species. The yellow passion fruit is an excellent model to investigate this issue, because its main pollinators are sensitive to deforestation. Seasonality also influences fruit set of crop species that are pollinated by bees. Climate determines plant flowering patterns and consequently affects pollinator activity. Little is known on effects of pollinators on crop quality in general, and particularly of many tropical fruits that have multiple fruiting seasons throughout the year, such as passion fruit. Our hypothesis is that the distance to the native vegetation and climate seasonality affect the pollination and fruit production of cultivated, hermaphrodite, self-incompatible, protandrous species that depend on large-sized bees to set fruit. We observed flowers of the yellow passion fruit in eight areas at different distances (600-4,000 m) from a dry seasonal forest (Caatinga). We compared the frequency of the main floral visitor (pollinators and robbers) visits and fruit set among areas at the beginning and end of the dry and rainy seasons. Xylocopa species were pollinators, and Apis mellifera, Trigona spinipes and a hummingbird were robbers. Xylocopa visits diminished with increasing distance to native remnants, converse to what was observed for the robbers at the beginning of the dry season. Fruit set was higher at the beginning of the dry season. The distance to the forest affected quality of fruits in terms of length, diameter and skin thickness, which all decreased with increase in remnant distance. Our results show that insect pollination is higher in the dry season, increasing profitability and reducing labour costs for the producer. Considering the influence of distance to native vegetation on pollination, robbery and fruit quality, our study reinforces the necessity for conservation of native vegetation remnants.
Assuntos
Ecossistema , Passiflora/crescimento & desenvolvimento , Brasil , Clima , Geografia , Chuva , Estações do Ano , TemperaturaRESUMO
Due to their importance as pollinators of many plant species, this study aimed to know the nest density, spatial distribution, and nesting substrates used by Xylocopa species in the Caatinga, a xerophilous vegetation of Northeastern Brazil. Three areas of Caatinga in the surroundings of passion fruit crops were sampled. The bee species found in these areas were Xylocopa grisescens Lepeletier and Xylocopa frontalis (Olivier). All nests were in Commiphora leptophloeos (Burseraceae) trees (n = 113). Phytosociological analysis showed that this tree species presented the highest absolute density (212.5 individuals/ha) and index of importance value (52.7). The distribution pattern of the C. leptophloeos was aggregated. The nests were located in dead and dried branches with an average diameter of 5.3 ± 2.0 cm (n = 43). The mean number of nests/tree was 3.1 ± 2.8 (n = 113). The less disturbed area showed 6.7 nests/ha and 4.2 nests/tree. In the disturbed areas, 0.9 nests/ha and 2.4 to 2.7 nests/tree were observed. The availability of substrate for nesting in the studied areas and its importance as a limiting factor for nesting are discussed.
Assuntos
Himenópteros , Comportamento de Nidação , Passiflora , Animais , Abelhas , Brasil , FrutasRESUMO
AIM: The purpose of this study was to identify placental and umbilical cord macroscopic changes and correlate them to maternal and fetal clinical events in hypertensive disorders of pregnancy (HDP). MATERIALS AND METHODS: The authors examined 150 placentas, 30 from each HDP group, totaling 120, and 30 from the control group. All placentas and umbilical cords were examined, recorded, and photographed. RESULTS: The mean placental weight in the control group (526.3 +/- 95.6 g) was greater than in the HDP (435.5 +/- 43.1 g). Calciphylaxis was the most common macroscopic change found in the control and HDP groups in 27 (90%) and 118 cases (98.3%), respectively. DISCUSSION: Pregnant women with HDP were relatively younger. In addition, due to low blood flow seen in HDP, the macroscopic changes found included lower placental weight, calciphylaxis in the maternal surface, and fibrin in the fetal surface. Because of all complications associated, most women with HDP had preterm infants who developed respiratory problems and had shorter umbilical cords.