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Visitantes florais e produ o de frutos em cultura de laranja ( Citrus sinensis L. Osbeck) = Floral visitors and fruit production on sweet orange crop ( Citrus sinensis L. Osbeck)
Lourdes Maria Gamito,Darclet Terezinha Malerbo-Souza
Acta Scientiarum : Animal Sciences , 2006,
Abstract: O presente experimento foi realizado em florada de laranja (Citrus sinensis L. Osbeck), variedade Pera-Rio, com os objetivos de estudar os insetos visitantes nas flores d e laranjeira, o seu comportamento nas flores, o tipo de coleta efetuada e o efeito dessas visitas na produ o de frutos, em quantidade e qualidade. Os dados de freqüência foram obtidos por contagem nos primeiros 10 minutos de cada horário, das 8h às 18h, em três dias distintos, percorrendo-se as linhas da cultura. O comportamento forrageiro de cada espécie de inseto foi avaliado através de observa es visuais, no decorrer do dia, no período experimental. Os insetos observados foram abelhas africanizadas Apis mellifera, Trigona spinipes e Tetragonisca angustula. As abelhas A. mellifera foram os visitantes florais maisfreqüentes e preferiram coletar néctar comparado ao pólen. Os bot es florais descobertos produziram mais frutos que os bot es florais cobertos. Os frutos decorrentes do tratamento coberto foram menores, mais ácidos e com menor quantidade de vitamina C que os frutos do tratamento descoberto. The present experiment was carried out in flowerage of sweet orange(Citrus sinensis L. Osbeck), Pera-rio variety, to study the insects involv ed in pollination, their behaviour in the flower (nectar or pollen collection) and the effect of the pollination on fruit production (quantity and quality). More frequent insects were recorded daily (counted during ten minutes, every hour) from 8:00 a.m. to 6:00 p.m., with three replications. The forage behaviour and nectar and/or pollen collect was also observed. The insect visitors onflowers were Africanized honey bee Apis mellifera, followed by stingless bees Trigona spinipes and Tetragonisca angustula. A. mellifera were the most frequent visitors and preferred to collectnectar than pollen. The uncovered flowers -buds produced more fruits than the covered ones. Another observation was that fruits derived from covered treatment were smaller, more acid and with less quantity of vitamin C than the uncovered ones.
Visitantes florais de Erythrina speciosa Andr. (Leguminosae)
Vitali-Veiga, Maria J.;Machado, Vera L.L.;
Revista Brasileira de Zoologia , 2000, DOI: 10.1590/S0101-81752000000200007
Abstract: inspite of etythrina species exhibit morphologic attributes for adaptation to pollination by nectarivorous birds mentioned in the literature, e. speciosa is pollinated by lots of bees (apinae and meliponinae) which show a great urban occurrence. systems of e. speciosa floral reproduction, fenology, diversity, frequency and constancy of insects visiting at different hours and flowering periods were studied. e. speciosa is biocompatible, but xenogamy is the predominant system of reproduction. a large diversity of insects visiting the inflorescences was observed, with predominance of bees. the bee species showed a higher frequency: apis mellifera linnaeus, 1758 (45,0 %), trigona spinipes (fabricius, 1793) (28,6%), trigona hyalinata (lepeletier, 1836) (12,2 %) and the ant zacryptoceruspusillus klug, 1824 (2,8 %). constant but not frequent were the bees (apidae) plebeia droryana (friese, 1900), friesella schrottkyi (friese, 1900), nannotrigona testaceicornis (lepeletier, 1836), tetragonisca angustula (latreille, 1811), the wasps (vespidae) polybia paulista ihering, 1896, protopolybia exigua (de saussure, 1854), agelaia pallipes (olivier. 1791), the ant (formicidae) pseudomyrmex sp. and the beetle (chrysomelidae) diabrotica speciosa (germar, 1824). e. speciosa flowers were visited by hummingbirds (trochilidae): eupetomena macroura (gmelin, 1788), clorostilbon aureoventris (d'orbigny & lafresnaye, 1838) and amazilia sp. the birds passer domeslicus (linnaeus, 1758) (ploceidae) and coereba flaveola (linnaeus, 1758) (emberizidac), also are present. the frequency and insect distribution were influenced by ambiental factors. temperature, light, time, barometric pressure, relative humidity and wind velocity were significantly correlated with insect numbers. there is a visit sequence, by floral resource disponibility during the day, conditioned by transport ability, insect numbers and colony necessity, which begins by a. mellifera followed by meliponid bees. these bees make the p
Visitantes florais de Lagerstroemia speciosa Pers: (Lythraceae)
Vitali-Veiga, Maria de Jesus;Dutra, Jo?o Cloves Stanzani;Machado, Vera Lígia Letízio;
Revista Brasileira de Zoologia , 1999, DOI: 10.1590/S0101-81751999000200006
Abstract: studies were carried out with lagerstroemia speciosa pers. on floral reproductive systems, diversity and constancy of visiting insects at different hours of day, the behaviour of these insects at the flowers and the influence of these environmental factors in relation to their visits. the fenology, anthesis and others particularity of this vegetal species was studied. a great diversity of insects was verified visiting the flowers with the predominance of bees. the most frequent and constant species encountered were: nannotrigona testaceicornis (lepeletier, 1836) (40,2%), tetragonisca angustula (latreille, 1811) (16,9%), apis mellifera linnaeus, 1758 (11,8%), plebeia droryana (friese, 1900) (9,1 %) e exomalopsis fulvofasciata (smith, 1879) (8,5%). the blossoms possessis features of melittophily syndrome and diurnal anthesis. the environmental factors influence the insects foraging activity, mainly temperature, light, time of day, humidity and wind speed. the effective pollinators were the large insects like bombus morio (swederus, 1787), bombus atratus (franklin, 1913), centris tarsata (smith, 1874), centris flavifrons fabricius, 1775, xylocopa suspecta camargo & moure, 1988, xylocopa frontalis (olivier, 1789) and eulaema nigrita lepeletier, 1841.
Utiliza??o dos recursos florais pelos visitantes em Sparattosperma leucanthum (Vell.) K. Schum. (Bignoniaceae)
Polatto, Leandro P.;Alves Jr., Valter V.;
Neotropical Entomology , 2008, DOI: 10.1590/S1519-566X2008000400006
Abstract: aiming to estimate the rate of exploitation of the floral resources of sparattosperma leucanthum (vell.) k. schum. as well as the interaction with their floral visitors in the pollination, the number of visits by flower was sampled, according to the type of visitation, the collected resource and the visitor's behavior during the forage for flowers. the floral visitors were grouped into seven guilds, organized in decreasing order of benefit to the s. leucanthum flower's pollination: effective pollinator, occasional pollinator, endogamic pollinator, generalist visitor, thievery visitor, thievery-pillager ant and pillager visitor. the total of 48.2 ± 8.84 visits were recorded by flower. nearly 50% of the visits resulted in nectar thief or pillage, which posed some problems to the reproduction of s. leucanthum, such as the drop in the attractiveness to pollinators and the harm to the flower's reproductive tissues. trigona spinipes (fabr.) (hymenoptera: apidae) was considered the most harmful species owing to the high frequency of pillage and forage. bombus sp1, however, was probably the species that pollinated s. lecanthum flowers the most, making use of the crossed pollination.
A estrutura da guilda de abelhas e vespas visitantes florais de Waltheria americana L. (Sterculiaceae)
Macedo, Jo?o F.;Martins, Rogério P.;
Anais da Sociedade Entomológica do Brasil , 1999, DOI: 10.1590/S0301-80591999000400005
Abstract: the number of flowers produced by the weed waltheria americana l (sterculiaceae) and the number of flowering dicot species were quantified in two sites at the campus of the universidade federal de minas gerais, to evaluate their seasonal relative importance as a source of nectar and pollen to a guild of 72 species of wasps and 37 species of bees. differences between the average number of flowering dicot species between the dry and rainy seasons were found in only one of the sites. a significant difference in the number of flowers produced by w. americana between the two seasons was found in only one of the sites. only the number of wasps visiting w. americana varied between seasons. seasonal variation in guild composition was observed in one of the sites and only the bees showed a strong variation in species composition along the year. there was a positive correlation between the number of flowering dicot species and both the number of bee visits, and the number of flowers of w. americana. however, there were no differences between seasons in the average of visits. on the other hand, there was no correlation between the number of wasp visits to w. americana and either the number of flowers of w. americana or the number of other flowering dicot species in one site. on average, wasps visit w. americana more frequently in the rainy season than in the dry one in one of the sites, but the inverse occurred in the other site. the daily flower visitation of wasps and bees was most intense, and similar, between nine and 13 h. because w. americana flowers year round and is a source of nectar for bees and wasps, its management could be important to maintain the diversity of bees and wasps in disturbed areas or agroecosystems, thus supporting insects which may act as pollinators and biological control agents, respectively.
Comportamento de abelhas visitantes florais de Lecythis lurida (Lecythidaceae) no norte do estado do Rio de Janeiro
Aguiar, Willian Moura;Gaglianone, Maria Cristina;
Revista Brasileira de Entomologia , 2008, DOI: 10.1590/S0085-56262008000200007
Abstract: this study describes and analyses the behavior of l. lurida flower visitors in fragments of tabuleiro lowland forest. this monoecious species flowered from october to january. the flowers opened between 5:30 and 10:00 a.m. and floral anthesis did not exceed one day. standardizing samples on flowers resulted in 172 bees, belonging to ten genera and 18 species. epicharis flava (42,3%), xylocopa frontalis (16,3%) and eufriesea surinamensis (11,6%) performed the highest relative frequencies, mainly occuring between 7:00 and 11:00a.m. centridini, euglossina and xylocopini bees took nectar on flowers and were considered effective pollinators. megachile collected pollen and also was potential pollinator. oxaea flavescens acted as nectar thief by piercing the flower hood. experiments of spontaneous autopollination indicated no fruit set and low fruit set (0,48%) was observed in flowers under natural conditions. as discussed for other zygomorphic flowers of lecythidaceae, the complex floral morphology restrict visitors to large or robust bees that can get into the flower through the floral hood. nevertheless centridini was the main pollinator group of l. lurida, which differs from the pollinators indicated in other studies on lecythidaceae in the amazonian region.
Biologia reprodutiva de Acacia mearnsii de wild. (Fabaceae) IV: visitantes florais
Alves, Eudes Maria Stiehl;Marins-Corder, Maisa Pimental;
Revista árvore , 2009, DOI: 10.1590/S0100-67622009000300006
Abstract: to ensure the success of the strategies of genetic improvement in tree species, knowledge of the reproductive biology of the species involved is essential. one of these critical factors in reproductive success of the genus acacia is the presence of vectors to pollination. the purpose of this study was to identify flower visitors to a commercial plantation of acacia mearnsii de wild. and quantify the polyads attached to the body surface of the insects. the observations were made from a tower in a commercial stand during flowering, in 2002 and 2003. during the day, flower visitors were captured with an entomological net and an air basket installed on a tractor. at night, insects were caught with light traps installed between the flowering crowns. insects belonging to orders coleoptera, hymenoptera, diptera, hemiptera and lepidoptera were observed. beetles of the species macrodactylus suturalis were considered dispersers of black wattle pollen, based on the high frequency of individuals in the population studied and the high quantity of polyads adhered to the body of the caught insects (x=229,36 polyads/insect). the amount of polyads verified on bees of the species apis mellifera was significantly greater (x=448,50 polyads/insect), but the frequency in the study area was insignificant. one of the recommended ways to increase the frequency of bees and wasps in black-watle commercial plantations is the maintenance of sources of nectar and the introduction of bee hives.
Anelamento e incis o anelar em fruteiras de caro o  [cached]
Sartori Ivar Antonio,Ilha Luciano Larruscahim Hamilton
Ciência Rural , 2005,
Abstract: O cultivo de pessegueiros é uma atividade de grande importancia econ mica no Sul do Brasil, e o Estado do Rio Grande do Sul se destaca como o maior produtor brasileiro. Grande parte dos pomares se encontram na Metade Sul do Estado. Um dos principais problemas da cultura para o consumo de frutas in natura é o tamanho reduzido das mesmas e a produ o concentrada, que dificultam a comercializa o. O anelamento e/ou a incis o anelar de ramos pode ser usada, com o intuito de aumentar a massa média das frutas e antecipar o período de colheita. Esta revis o busca encontrar dados referentes à época de execu o, cuidados necessários, problemas associados e aspectos fisiológicos do anelamento e incis o anelar de ramos em fruteiras de caro o, principalmente pêssegos, ameixas e nectarinas de maior express o comercial no sul do Brasil. O anelamento e/ou a incis o anelar torna-se uma prática útil para melhorar a qualidade da fruta e antecipar a colheita de cultivares de matura o precoce. Contudo, faz-se necessário a realiza o de estudos locais para as diferentes espécies e cultivares. A prática da incis o anelar é mais recomendada pela facilidade de execu o e com resposta semelhante ao anelamento. A época mais indicada para a realiza o da incis o anelar é na fase de lignifica o do endocarpo. Recomenda es devem ser específicas para cada situa o e o anelamento, em conjunto com outras práticas, poderá promover a antecipa o da matura o e contribuir para melhorar a qualidade organoléptica das frutas.
Lepidópteros visitantes florais de Stachytarpheta cayennensis (Rich.) Vahl (Verbenaceae) em remanescente de Mata Atlantica, Minas Gerais, Brasil
Fonseca, Nilson G.;Kumagai, Alice F.;Mielke, Olaf H. H.;
Revista Brasileira de Entomologia , 2006, DOI: 10.1590/S0085-56262006000300010
Abstract: the composition and seasonality of the lepidopteran community visiting inflorescences of s. cayennensis at esta??o ambiental de peti, were analyzed. the visits of 445 lepidopterans belonging to 98 species, distributed in 6 families, were registered. hesperiidae (81,8%), pieridae (10,8%), lycaenidae (3,6%), nymphalidae (2,2%), papilionidae (1,3%), and sesiidae (0,3%). skippers presented the highest species richness, with 70 species. only four of these had a relative abundance above 5% (pyrgus orcus (stoll, 1780), pompeius pompeius (latreille, [1824]), urbanus dorantes dorantes (stoll, 1790) and corticea corticea (pl?tz, 1882)). according to palma classification, two species were common, 12 intermediary and 84 were considered rare. diversity and evenness value were high (h'= 3.98 and e = 0.87). there was a sharp difference in the composition and abundance of the species throughout the year, attributed mainly to a higher richness and abundance during the rainy season. accordingly, the similarity between rainy and dry season was relatively low, with 18 common species, 25 present only in the dry season and 93 during the wet season. the period of highest foraging activity corresponded to temperatures between 23 and 32oc and the highest abundance were registered about 10:00h.
As abelhas eussociais (Hymenoptera, Apidae) visitantes florais em um ecossistema de dunas continentais no médio Rio S?o Francisco, Bahia, Brasil
Neves, Edinaldo Luz das;Viana, Blandina Felipe;
Revista Brasileira de Entomologia , 2002, DOI: 10.1590/S0085-56262002000400012
Abstract: highly eusocial bees (hymenoptera, apidae) flower visitors in a continental sand dune ecosystem from the medium s?o francisco river, bahia, brazil. a community of highly eusocial bees in sand dunes, covered with caatinga vegetation, in the medium s?o francisco river, bahia (10o47' 37"s and 42o49' 25"w) was studied. the local climate is semi arid and hot, with mean temperature of 25.7 oc and annual precipitation of 653.8 mm. censuses took place every two months, from february to december of 2000. the bees were sampled on flowers with entomological nets, from 6:00 a.m. to 5:00 p.m. a total of 2,147 individuals of eight species of apinae were found, of which apis mellifera linnaeus (40.2%), trigona spinipes (fabricius) (28.7%) and frieseomelitta silvestri languida moure (14.7%) were the predominant species. the diversity was h' = 1.53 and the evenness e' = 0.73. the bees were active during the whole year, but there was a significant variation in the monthly abundance of individuals (c2= 799.55; df= 35; p<0.0001). the daily activity was greater between 6:00 a.m. and 8:00 a.m. the low bee diversity observed is a consequence of the low richness of botanical species and of the small amount of sites for the bees' nests. the community of highly eusocial bees from the dunes presents organization patterns similar to those observed in other caatinga areas, albeit with some particularities.
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