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Search Results: 1 - 10 of 19 matches for " melittophily "
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Biologia reprodutiva de Cattleya eldorado, uma espécie de Orchidaceae das campinas amaz?nicas
Storti, Eliana Fernandez;Braga, Pedro Ivo Soares;Storti Filho, Atilio;
Acta Amazonica , 2011, DOI: 10.1590/S0044-59672011000300005
Abstract: the orchid plants are highly prized for their lush exotic flowers. it is the largest plant family with more than 24000 species, which indicates a high diversity of forms and adaptations to different environments, including the capacity to attract, deceive and manipulate visitors involved in cross-pollination. cattleya eldorado occurs in areas of white sand campinas, a typical vegetation type of the amazon region, which is under strong anthropogenic pressure. this work's main objectives to know the biological processes of c. eldorado providing subsidies to maintain and manage it in its natural habitat. this study was conducted from 2000 to 2006 in the campina biological reserve, during its flowering period. c. eldorado is an epiphytic orchid species that has the melittophyly syndrome and is adapted to its pollinator, the bee eulaema mocsaryi recognizing their flowers by smell and by visual stimuli, through their color and reflection of ultraviolet light. c. eldorado is self-compatible, even if it requires a pollinating agent for the transfer of the pollinarium until its deposition in the stigmatic cavity of the flower.
Estratégias fenológicas de Senna cana (Nees & Mart.) H.S. Irwin & Barneby (Fabaceae: Caesalpinioideae) como mecanismo eficiente para atra??o de polinizadores
Souza, Isys Mascarenhas;Coutinho, Karoline;Funch, Ligia Silveira;
Acta Botanica Brasilica , 2012, DOI: 10.1590/S0102-33062012000200019
Abstract: the present work evaluated the importance of the phenological strategies of senna cana in attracting floral visitors and pollinators in an riparian forest along the len?óis river, in chapada diamantina, bahia, brazil. vegetative and reproductive phenological observations (leaf fall, leaf flushing, flowering, and fruiting) were made on a monthly basis among a group of 10 individuals. the floral biology patterns observed included: anthesis, duration of the flowers, stigma receptivity, pollen viability, and the presence of osmophores and pigments that reflect uv light. reproductive mechanisms were examined by testing manual and natural self-pollination as well as cross-pollination. visitors and pollinators were identified, and the time, duration, and frequency of their visitation, as well as their behavior, were noted. senna cana is an episodic evergreen species showing seasonal and highly synchronous reproductive events (intermediate flowering after a rainy period, and long fruiting during the dry period). these flowering characteristics, in addition to the syndrome of melittophily, are important strategies for attracting floral visitors (including xylocopa frontalis and x. grisescens, which are potential pollinators). the self-incompatibility and maximization of fruit production through cross-pollination represent reproductive mechanisms favored by the phenological strategies and the pollination syndrome demonstrated by this species.
Fenologia reprodutiva e sistema de poliniza??o de Ziziphus joazeiro Mart. (Rhamnaceae): atua??o de Apis mellifera e de visitantes florais autóctones como polinizadores
Nadia, Tarcila de Lima;Machado, Isabel Cristina;Lopes, Ariadna Valentina;
Acta Botanica Brasilica , 2007, DOI: 10.1590/S0102-33062007000400008
Abstract: (reproductive phenology and pollination system of ziziphus joazeiro mart. (rhamnaceae): the role of apis mellifera and autochthonous floral visitors as pollinators). ziziphus joazeiro is an endemic species of the caatinga with great economic importance, whose reproductive biology is poorly understood. this paper analyses the reproductive phenology, floral biology and pollination system of ziziphus joazeiro at cariri paraibano, northeastern brazil. flowering and fruiting periods occurred at the end of the dry season and beginning of the rainy season, with peaks in december (flowering) and february (fruiting). the green, dish-shaped flowers last about 12 hours and have a large yellow nectary surrounding the gynoecium. protandry occurs associated with heterodichogamy, another type of dichogamy. ziziphus joazeiro produces little nectar (1 μl) but with a high sugar concentration (75%). floral visitors were wasps, bees and flies. apis mellifera had the highest frequency of visits (77.5%), followed by wasps (20.4%), both acting as effective pollinators. flies and other bee species had a lower percentage of visits (2.1%) and acted as nectar robbers. the high rate of initial fruit development per inflorescence suggests high pollinator efficiency, since the dichogamic mechanism prevents the occurrence of spontaneous self-pollination and geitonogamy.
Solanaceae composition, pollination and seed dispersal syndromes in Mexican mountain cloud forest
Albuquerque, Lidiamar Barbosa;Velázquez, Alejandro;Mayorga-Saucedo, Rafel;
Acta Botanica Brasilica , 2006, DOI: 10.1590/S0102-33062006000300010
Abstract: in this work we hypothesised that solanaceae species composition and pollination and seed dispersal syndromes change according to the degree of disturbance. hence, the aim of this study is to analyze how the species composition of solanaceae changes along disturbance gradients of mountain cloud forest, and to establish how solanaceae pollination and seed dispersal syndromes vary along the same gradients. the study concentrates on the mountain cloud forests in hidalgo, mexico. solanaceae species collection was carried out along transects, laid out alongside paths and secondary roads. pollination and seed dispersal syndromes for all species were recorded based on floral and fruit morphological traits. from the 500 sample units surveyed, 392 contained 25 solanaceae species. the (dis)similarity among sample units highlighted a major division: the first group harboured species more commonly found in less disturbed and more humid conditions, whereas the second group contained species more commonly found in contrasting conditions. melittophily pollination syndromes turned out to be equally relevant in the environmental conditions of both groups. with regard to seed dispersal syndromes, ornithochory (45.8%) prevailed over chiropterochory (37.5%) in group i less disturbed and more humid areas, whereas chiropterochory (50%) prevailed within group ii.
Auto-incompatibilidade em Miconia ciliata (L.C.Rich.) DC. (Miconieae - Melastomataceae)
Melo, Gladys Flavia de;Machado, Isabel Cristina;
Acta Botanica Brasilica , 1998, DOI: 10.1590/S0102-33061998000200002
Abstract: miconia ciliata is a shrub whith flowers over a period of 11 months. the flowers are hermaphrodite with diurnal anthesis. probably miconia ciliata exhibits gametophytic incompatibility - pollen tube growth's interrupted in the style. bees of the family halictidae were observed to use the vibration technique to extract pollen (buzz pollination). only few flowers per inflorescence open each day. which probably induces the effective pollinators to visit a larger number of inflorescence in each individual plant, promoting cross pollination. reproductive success in miconia ciliata is favoured by the high frequency of pollinators visits, high p/o ration and high pollen fertility.
Sistema de poliniza??o e reprodu??o de Byrsonima sericea DC (Malpighiaceae)
Teixeira, Luciana Almeida Gomes;Machado, Isabel Cristina;
Acta Botanica Brasilica , 2000, DOI: 10.1590/S0102-33062000000300011
Abstract: the pollination, the reproductive system and the flowering phenology of byrsonima sericea dc. were studied from october/1997 to february/1998 in the ecological reserve of "dois irm?os", in recife (pe). byrsonima sericea is a woody species (3-20 m tall), flowering from october to february. the flowers are hermaphrodites, zygomorphic, arranged in terminal inflorescence, of the raceme type. the corolla is yellow and has five clawed and fringed petals. the superior one is modified as a flag. the calyx has five sepals with 10 elliptic epithelial oil glands, the elaiophores. in some individuals these elaiophores are absent. the androecium has 10 stamens, the anthers are rimoses and the dehiscence occurs at the pre-anthesis phase. pollen viability was 93,3% and 98,3%, respectively to individuals with and without elaiophores, the number of pollen grains per anther was 1.216,66 and 923,33, and the pollen/ovule (p/o) ratio was 308.000 and 405.500. floral visitors were only female bees of the families anthophoridae (that collected oil and pollen), apidae and halictidae (that collected only pollen). based on the strategies and rewards (oil and pollen), the high p/o ratio, and mainly because of the absence of fruits from self-pollination tests, it is concluded that this species is xenogamic.
Biologia floral e heterostilia em Vismia guianensis (Aubl.) Choisy (Clusiaceae)
Santos, Mary Janice Lima dos;Machado, Isabel Cristina;
Acta Botanica Brasilica , 1998, DOI: 10.1590/S0102-33061998000400014
Abstract: the floral and reproductive biology of vistnia guianensis was studied in the ecological reserve of "dois irm?os", in recife (pe), northeastern brazil, from november/1997 to february/1998. v guianensis is a shrubby species, wherein the flowers, heterostyled of the dimorphic type, are arranged in terminal panicles. the anthesis is diurnal and the flowers last for one day. nectar volume was about 2,0}il, the sugar concentration varying from 46% to 68% in the two types of flowers. pollen viability was ca. 93% for both long and short styled-flowers. v guianensis is a self-incompatible species. only the intermorph pollinations produced fruits (55-65%). visits by polybia sp. (vespidae) and several species of bees were observed to flowers of v. guianensis. hylaeus sp. (colletidae), and augochloropsis sp. (halictidae) were the most frequent visitors, and were considered, together with polybia sp., the effective pollinators. due to the xenogamic reproductive system associated to the heterostylous mechanism, the pollinators have a fundamental role in promoting sexual reproduction in this plant species.
Pollination and dispersal systems in a Cerrado remnant (Brazilian Savanna) in Southeastern Brazil
Ishara, Katia Losano;Maimoni-Rodella, Rita de Cassia Sindr?nia;
Brazilian Archives of Biology and Technology , 2011, DOI: 10.1590/S1516-89132011000300025
Abstract: the aim of this work was to identify the pollination and dispersal systems among the species in a disjunct marginal cerrado area and to compare the frequency of these systems to those found in other neotropical vegetation. the floral and diaspore traits and the pollination and dispersal systems of 176 species were analysed in a cerrado remnant in southeastern brazil. the most frequent pollination system was melittophily (63% of the studied species) with the remaining 37% distributed among diverse pollination systems. zoochory was the predominant system of dispersal (44.9%). the frequencies of melittophily and zoochory observed in diverse tropical areas were the main feature that allowed the formation of distinct groups in the dendrograms generated by cluster analysis.
Sistemas de poliniza??o e de reprodu??o de três espécies de Jatropha (Euphorbiaceae) na Caatinga, semi-árido do Brasil
Neves, Edinaldo Luz das;Machado, Isabel Cristina;Viana, Blandina Felipe;
Brazilian Journal of Botany , 2011, DOI: 10.1590/S0100-84042011000400009
Abstract: the floral biology, nectar production behavior, floral visitors, and reproductive systems of jatropha ribifolia (pohl) baill. (euphorbiaceae) is presented and compared of those of j. mollissima (pohl) baill. and j. mutabilis (pohl) baill. the study was undertaken in an area of hyperxerophilous caatinga at the esta??o biológica de canudos, bahia state, brazil, from may 2005 to june 2007. the flowers of the three species are disposed in a protogynic dichasium. in j. ribifolia both staminate and pistilate flowers last for about 48 hours and flower opening is diurnal, while in j. mollissima and j. mutabilis the staminate flowers last from 12 to 15 hours and the pistilate flowers from 36 to 48 hours, with flower opening occurring at sunset. nectar production, pollen viability, and stigma receptivity initiate soon after full opening of both floral types, and sexual activity overlaps until senescence. nectar production varied throughout the day, with higher production by the pistilate flowers; pollen viability and stigma receptivity during the lifetime of the flower occurred in all three species. significant differences occurred between the reproductive system treatments of j. mollissima (kw = 59.796), j. mutabilis (kw = 59.058), or j. ribifolia (kw = 63.660). the three species produced fruits by experimental geitonogamy as well as experimental xenogamy, while only j. ribifolia produced fruits by spontaneous geitonogamy. the bees apis mellifera, xylocopa frontalis and x. grisescens and the hummingbirds chlorostilbon lucidus and anopetia gounellei are potential pollinators for j. mollissima and j. mutabilis and a. mellifera and x. grisescens are potential pollinators for j. ribifolia. the diversity of anthophiles on flowers of the three species allows pollen flow and fruit set. on the other hand asynchronous flowering and differences of flower morphology and anthesis help maintain the reproductive isolation and prevent the loss of interspecific pollen due to sharing of poll
Fenologia reprodutiva, biologia floral e polinizadores de duas espécies simpátricas de Marantaceae em um fragmento de Floresta Atlantica, Nordeste do Brasil
Leite, Ana Virgínia;Machado, Isabel Cristina;
Brazilian Journal of Botany , 2007, DOI: 10.1590/S0100-84042007000200007
Abstract: we analyzed the flowering, fruiting and the pollination biology of two species of marantaceae: ischnosiphon gracilis (rudge) koern. and stromanthe porteana a. gris. observations were carried out in natural populations at the "parque estadual dois irm?os" (8o7'30" s and 34o52'30" w), a remnant of atlantic forest in pernambuco. we verified a continuous phenological pattern in both species, with different flowering and fruiting peaks. inflorescences of i. gracilis produced 14.4 ± 3.4 flowers and 1.3 ± 0.6 fruits whereas s. porteana produced 125.4 ± 14.8 flowers and 7.4 ± 4.9 fruits. we verified low pollen/ovule ratio and reduced fruit set under natural pollination for the studied species. sugar concentration in the nectar of i. gracilis flowers was high (26%-32%), characteristic of bee flowers, and in s. portena the nectar was less concentrated (20%), common to hummingbird flowers. ischnosiphon gracilis is pollinated by three species of euglossini bees (euglossa sp., eulaema bombiformis and e. cingulata), whereas s. porteana is pollinated by one species of euglossini bee (eufriesea surinamensis) and two species of hummingbirds (phaethornis ruber and amazilia versicolor). the differences between the flowers of these species avoid the sharing and competition for pollinators, which can assure their maintenance in the habitat. however, in a long term, the low fruit set can affect the population structure by decreasing the reproductive success of these species.
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