Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto

About: Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto is a based out in . It is known for research contribution in the topics: Population & Catalysis. The organization has 2143 authors who have published 3674 publications receiving 71071 citations. The organization is also known as: FFCLRP & FFCLRP-USP.

Nesting biology of Centris (Hemisiella) vittata Lepeletier in southeastern Brazil (Hymenoptera, Apidae, Centridini)

Abstract: Nests of Centris vittata were obtained from trap-nests at Santa Carlota Farm, Cajuru, SP, Brazil. The bees nested in bamboo canes ranging from 8.5 to 24.7 cm in length and from 0.9 to 1.9 cm in diameter. The bees constructed their nests with a mixture of soil and an oily substance. Com- pleted nests had 1-8 urn-shaped cells arranged in a linear series, separated by a space filled with loose soil. The nest plugs resembled the bottoms of cells and were externally covered with an oily mate- rial. In some cases they were also covered with an another yellowish, sticky substance of unknown origin. The innermost cells of the nests produced females and the outermost cells males, resulting in proterandry. Females were significantly larger than males, and no dimorphism in males was found. Nests were parasitized by the megachilid bee, Coelioxys sp., the bombyliid fly, Anthrax sp. and by meloid beetles. C. vittata nested exclusively in the hot and wet season (September-April), produc- ing at least two generations. © Inra/DIB/AGIB/Elsevier, Paris

She’s my girl - male accessory gland products and their function in the reproductive biology of social bees

Abstract: Les glandes accessoires mâles des insectes (MAG) produisent une variete de composes, dont des acides amines, des amines biogenes, des proteines, des hydrates de carbone et des lipides. Leurs secretions ont deux fonctions principales : la premiere, qui est probablement l'originelle, sert a aider le transfert de sperme (spermatophore ou fluide seminal) ; la seconde consiste a s'assurer que le mâle a l'exclusivite de la paternite apres accouplement avec une femelle. On a en effet montre chez de nombreux insectes que les composes des MAG manipulaient le comportement reproducteur et la physiologie de la reproduction en reduisant la receptivite et en stimulant la production d'oeufs et la ponte. Certains composes des MAG peuvent en outre contribuer a reduire la longevite de la femelle. Les differents niveaux de socialite et la large gamme de strategies d'accouplement font des abeilles une base d'etude interessante pour les produits des MAG et leurs fonctions supposees. Chez le bourdon terrestre, Bombus terrestris, on a montre que les lipides presents dans le bouchon d'accouplement, en particulier l'acide linoleique, empechaient les reines de subir d'autres tentatives d'accouplement. Chez le genre Apis, le signe de fecondation est une structure hautement complexe constituee du bulbe de l'endophallus, des plaques cervicales et aussi de mucus coagule et de la secretion collante des cornes. Les glandes a mucus des mâles d'Apis mellifera synthetisent de grandes quantites de proteines au cours de la maturation sexuelle. Les glandes des mâles qui viennent de naitre secretent un melange complexe de proteines, qui se transforme peu a peu en un ensemble reduit dans lequel dominent les proteines de poids moleculaire compris entre 43 et 47,5 kDa. Le systeme endocrinien joue un role majeur dans le controle du processus de maturation de la synthese des proteines des MAG, avec presence d'ecdysteroides qui agissent comme regulateurs negatifs. Les recherches sur l'activite biologique des extraits de MAG de l'Abeille domestique n'ont revele jusqu'a ce jour que des composes proteiniques potentiellement toxiques. En liaison avec les lipides apparemment omnipresents des secretions des MAG, ces proteines peuvent aider a reduire la transmission de bacteries au cours des accouplements qui s'ensuivent. Les glandes accessoires mâles sont absentes du systeme reproducteur chez les abeilles sans aiguillon, generalement monandres, et il a ete suggere que la capsule genitale du mâle qui reste dans le tractus femelle apres l'accouplement pourrait servir de stimulus mecanique pour stimuler l'ovogenese et la ponte.

Stingless bees, Melipona fasciculata, as efficient pollinators of eggplant (Solanum melongena) in greenhouses

Abstract: Detailed studies of the behavior of pollinators allow insights into pollination mechanisms and may indicate which pollinators are more efficient for a particular plant species. Our aim was to evaluate if Melipona fasciculata is an efficient pollinator of eggplant (Solanum melongena L., Solanaceae) in greenhouses. We analyzed (1) the colony foraging pattern of M. fasciculata in greenhouses, (2) the behavior of bees during the visits to flowers, and (3) fruit set and fruit quality after different pollination treatments (hand pollination: autogamy, geitonogamy, xenogamy; bee pollination). Our results show that M. fasciculata is an efficient pollinator of eggplants and, consequently, may be a viable alternative to bumblebees in Brazil.

Analysis of the Nicotiana tabacum stigma/style transcriptome reveals gene expression differences between wet and dry stigma species.

Abstract: The success of plant reproduction depends on pollen-pistil interactions occurring at the stigma/style. These interactions vary depending on the stigma type: wet or dry. Tobacco (Nicotiana tabacum) represents a model of wet stigma, and its stigmas/styles express genes to accomplish the appropriate functions. For a large-scale study of gene expression during tobacco pistil development and preparation for pollination, we generated 11,216 high-quality expressed sequence tags (ESTs) from stigmas/styles and created the TOBEST database. These ESTs were assembled in 6,177 clusters, from which 52.1% are pistil transcripts/genes of unknown function. The 21 clusters with the highest number of ESTs (putative higher expression levels) correspond to genes associated with defense mechanisms or pollen-pistil interactions. The database analysis unraveled tobacco sequences homologous to the Arabidopsis (Arabidopsis thaliana) genes involved in specifying pistil identity or determining normal pistil morphology and function. Additionally, 782 independent clusters were examined by macroarray, revealing 46 stigma/style preferentially expressed genes. Real-time reverse transcription-polymerase chain reaction experiments validated the pistil-preferential expression for nine out of 10 genes tested. A search for these 46 genes in the Arabidopsis pistil data sets demonstrated that only 11 sequences, with putative equivalent molecular functions, are expressed in this dry stigma species. The reverse search for the Arabidopsis pistil genes in the TOBEST exposed a partial overlap between these dry and wet stigma transcriptomes. The TOBEST represents the most extensive survey of gene expression in the stigmas/styles of wet stigma plants, and our results indicate that wet and dry stigmas/styles express common as well as distinct genes in preparation for the pollination process.