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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Pollination Ecology and Demography of a Deceptive Orchid

Walsh, Ryan Patrick 07 August 2013 (has links)
No description available.
52

Systematics, Phylogeography, Fungal Associations, and Photosynthesis Gene Evolution in the Fully Mycoheterotrophic Corallorhiza striata Species Complex (Orchidaceae: Epidendroideae)

Barrett, Craig F. 26 August 2010 (has links)
No description available.
53

The role of mycorrhizal fungi in nutrient supply and habitat specificity of the rare mycoheterotrophic underground orchid, Rhizanthella gardneri

Bougoure, Jeremy J. January 2009 (has links)
Rhizanthella gardneri (Rogers) is a critically endangered orchid restricted to two isolated regions of south-western Australia. Rhizanthella gardneri is an entirely subterranean mycoheterotrophic species that purportedly forms a tripartite relationship with a mycorrhizal fungus (Ceratobasidiales) that links with an autotrophic shrub of the Melaleuca uncinata complex to acquire nutrients. Whether the rarity of R. gardneri is intrinsic is overshadowed by the recent effect of extrinsic factors that means R. gardneri requires some form of conservation and may also be a viable candidate for restoration. To create an integrated conservation strategy for R. gardneri, reasons for its decline and knowledge of its biological and ecological functioning must be elucidated. This thesis focuses on three key questions; 1) what are the habitat requirements and limitations to R. gardneri survival; 2) what is the identity and specificity of the fungus R. gardneri forms mycorrhizas with; and 3) does R. gardneri form a nutrient-sharing tripartite relationship with a mycorrhizal fungus and autotrophic shrub. Key climate, soil and vegetation characteristics of known R. gardneri habitats were quantified to provide baseline data for monitoring known R. gardneri populations, to better understand how R. gardneri interacts with its habitat, and to identify possible new sites for R. gardneri introduction. Habitats of the two known R. gardneri populations differed considerably in soil chemistry, Melaleuca structure and Melaleuca productivity. Individual sites within populations were relatively similar in all attributes measured while overall Northern and Southern habitats were distinct from each other. These results suggest that R. gardneri can tolerate a range of conditions and may be more widespread than previously thought, given that there are extensive areas of Melaleuca thickets with similar habitat characteristics across south-western Australia. The fungus forming mycorrhizas with R. gardneri was identified, using nuclear ribosomal DNA sequences, as a Rhizoctonia-type fungus within the Ceratobasidiales. All fungi isolated from R. gardneri individuals representative of its currently known distribution were genetically similar, suggesting R. gardneri is highly dependent on this specific fungal species. Given that R. gardneri appears to exclusively associate with a specific fungal species, species-specific molecular primers were designed and used to analyse the fungi’s presence in known and potential R. gardneri habitats. These results 6 suggest that the fungus exists beyond the known R. gardneri habitats and gives hope to finding new populations.
54

The role of mycorrhizal fungi in nutrient supply and habitat specificity of the rare mycoheterotrophic underground orchid, Rhizanthella gardneri

Bougoure, Jeremy J. January 2009 (has links)
Rhizanthella gardneri (Rogers) is a critically endangered orchid restricted to two isolated regions of south-western Australia. Rhizanthella gardneri is an entirely subterranean mycoheterotrophic species that purportedly forms a tripartite relationship with a mycorrhizal fungus (Ceratobasidiales) that links with an autotrophic shrub of the Melaleuca uncinata complex to acquire nutrients. Whether the rarity of R. gardneri is intrinsic is overshadowed by the recent effect of extrinsic factors that means R. gardneri requires some form of conservation and may also be a viable candidate for restoration. To create an integrated conservation strategy for R. gardneri, reasons for its decline and knowledge of its biological and ecological functioning must be elucidated. This thesis focuses on three key questions; 1) what are the habitat requirements and limitations to R. gardneri survival; 2) what is the identity and specificity of the fungus R. gardneri forms mycorrhizas with; and 3) does R. gardneri form a nutrient-sharing tripartite relationship with a mycorrhizal fungus and autotrophic shrub. Key climate, soil and vegetation characteristics of known R. gardneri habitats were quantified to provide baseline data for monitoring known R. gardneri populations, to better understand how R. gardneri interacts with its habitat, and to identify possible new sites for R. gardneri introduction. Habitats of the two known R. gardneri populations differed considerably in soil chemistry, Melaleuca structure and Melaleuca productivity. Individual sites within populations were relatively similar in all attributes measured while overall Northern and Southern habitats were distinct from each other. These results suggest that R. gardneri can tolerate a range of conditions and may be more widespread than previously thought, given that there are extensive areas of Melaleuca thickets with similar habitat characteristics across south-western Australia. The fungus forming mycorrhizas with R. gardneri was identified, using nuclear ribosomal DNA sequences, as a Rhizoctonia-type fungus within the Ceratobasidiales. All fungi isolated from R. gardneri individuals representative of its currently known distribution were genetically similar, suggesting R. gardneri is highly dependent on this specific fungal species. Given that R. gardneri appears to exclusively associate with a specific fungal species, species-specific molecular primers were designed and used to analyse the fungi’s presence in known and potential R. gardneri habitats. These results 6 suggest that the fungus exists beyond the known R. gardneri habitats and gives hope to finding new populations.
55

Gegužraibinių augalų populiacijų vertinimas Šveicarijos miško europinės svarbos buveinėse / Evaluation of orchid plant population in Šveicarija forest habitats of European interest

Antonovas, Donatas 16 June 2014 (has links)
Magistro darbe tiriamas gegužraibinių (Orchidaceae) šeimos augalų populiacijų gyvybingumas priklausomai nuo EB buveinių tvarkymo intensyvumo Šveicarijos miško BAST. Darbo objektas – Šveicarijos miško BAST gegužraibinių (Orchidaceae) augalų populiacijos. Darbo tikslas – įvertinti gegužraibinių (Orchidaceae) šeimos populiacijų gausumą skirtinguose tvarkymo plotuose, priklausomai nuo gamtotvarkos darbų reguliarumo. Darbo metodai – gegužraibinių (Orchidaceae) augalų individų apskaita. Darbo rezultatai. Vykdant gamtotvarkos projektą, Neries regioniniam parkui priskirtoje teritorijoje, Šveicarijos miško pelkinėse buveinėse, kurios nuolatos turi vandens perteklių ir yra svarbios biologinei įvairovei buvo vertinamas gegužraibinių (Orchidaceae) augalų gausumas priklausomai nuo buveinių tvarkymo intensyvumo. Projekto metu, siekiant nustatyti augalų gausumą buveinėse, buvo įrengta 20 vieno kvadratinio metro barelių 4 skirtingose EU buveinėse. Populiacijos buveinėse buvo vertintos pagal tokį tvarkymo intensyvumą: intensyviai prižiūrimos, neintensyviai prižiūrimos, natūralios arba netvarkomos buveinės. Pagal tyrimų rezultatus, galima patvirtinti hipotezę, kad gegužraibinių (Orchidaceae) šeimos populiacijos, Šveicarijos BAST, tiesiogiai priklauso nuo buveinių tvarkymo intensyvumo buveinėse. / This article analyses the continuity of nature restoration project, ongoing since 2008 in the area of Šveicarija forest, in Vilnius district, which occupies 210 ha, influence for European importance habitats and protected species populations. Subject of the research – Orchid (Orchidaceae) plants populations of Šveicarija forest. Aim of the research – to evaluate the orchid (Orchidaceae) plants density in Šveicarija forest, European importance habitats, due to restoration intensity. Methodology – evaluation of orchid (Orchidaceae) plants in 1m2. Results. During the project in the area supervised by Neris Regional Park, wetlands and habitats with excess water are very important for biodiversity and are always maintained. During the study, abundance of orchid (Orchidaceae) plants populations was assessed in 4 EU habitats, where 20 different 1 square meter plots were established. Populations of plants were evaluated according to the intensity of habitat management: regularly managed, partially managed and naturally managing itself. According to the research results, we can confirm findings that the populations of orchids (Orchidaceae) plants species in the Šveicarija forest directly depend on the management intensity of forest habitat.
56

Platanthera blephariglottis : une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec

Laroche, Vincent 12 1900 (has links)
Ce mémoire visait à déterminer si la platanthère à gorge frangée (Platanthera blephariglottis var. blephariglottis), une orchidée, est une espèce indicatrice de l’intégrité écologique des tourbières ombrotrophes. Les indicateurs d’intégrité écologique sont des outils indispensables pour évaluer efficacement les composantes d’un écosystème. Les résultats indiquent que l’abondance de la platanthère est fortement liée à l’indice de qualité floristique (FQAI). Le FQAI est aussi un excellent prédicateur de la présence de l’espèce, avec un taux de succès à 87%. D’autre part, l’abondance de l’orchidée est négativement affectée par les activités anthropiques et la matrice environnante. D’un point de vue descriptif, les habitats renfermant une grande abondance d’orchidées sont caractérisés par une faible microtopographie de surface et un recouvrement important de bryophytes et d’éricacées de petite taille. Globalement, ce mémoire a montré que la platanthère renferme un potentiel pour être indicatrice de l’intégrité écologique des tourbières ombrotrophes au Québec. / The aim of this study was to evaluate whether White Fringed Orchid (Platanthera blephariglottis var. blephariglottis) can be used as an indicator of Sphagnum bog integrity. Ecological indicators of integrity are important tools as it is impossible to monitor efficiently all components of an ecosystem. Results indicate that White Fringed Orchid abundance is highly linked with floristic quality assessment index (FQAI). FQAI is also a good predictor of presence of the species, with an accuracy of 87%. On the other hand, orchid abundance is negatively affected by anthropogenic activities and the environmental matrix. Similarly, peatlands having low edge effect are characterized by higher orchid abundance than those more influenced by edges. From a descriptive perspective, high orchid abundance habitat is characterized by low surface microtopography, high bryophyte and small ericaceous covers. Globally, this study has shown that White Fringed Orchid has potential to evaluate ecological integrity in Sphagnum bogs in Québec.
57

Análise morfofisiológica de microplântulas de Cattleya labiata Lindley e Cattleya eldorado Linden (Orchidaceae) sob efeito do paclobutrazol / Morphophysiological analysis of microplantlets of Cattleya labiata Linden and Cattleya eldorado Lindley (Orchidaceae) under the effect of paclobutrazol

Righeto, Marcos Vinicius Latanze 03 February 2012 (has links)
As espécies Cattleya labiata Lindley e a Cattleya eldorado Linden, nativas da Mata Atlântica e Amazônia, respectivamente, encontram-se sob forte risco de desaparecimento na natureza, sendo, portanto, necessário o desenvolvimento de métodos eficientes de propagação de suas mudas, dentre os quais se destaca a micropropagação. A eficiência do cultivo in vitro de orquídeas está associada aos meios de cultura utilizados e, principalmente, aos reguladores de crescimento. O trabalho teve como objetivo avaliar a influência de paclobutrazol (PBZ) no desenvolvimento das microplântulas cultivadas in vitro. Plântulas provenientes de germinação in vitro, com 1,0 ± 0,2 cm de comprimento, foram utilizadas no estudo. No primeiro experimento, utilizou-se como controle o meio de cultura MS isento de reguladores de crescimento vegetal. Nos tratamentos, o meio MS foi suplementado com quatro concentrações de PBZ 1,0; 2,0; 4,0 e 6,0 mg.L-1; com ácido naftalenoacético (ANA) 1,0 mg.L-1 associado a 6-benzilaminopurina (BAP) 1,0 mg.L-1 e com a combinação de 4,0 mg.L-1 PBZ, com 1,0 mg.L-1 ANA e 1,0 mg.L-1 BAP. As avaliações morfológicas, número de brotos, comprimento da parte aérea (CPA), comprimento da maior raiz (CMR) e comprimento da lâmina foliar (CLF), foram realizadas no início do experimento e nos subcultivos a cada 40 dias, durante 160 dias. O delineamento experimental foi inteiramente casualizado em arranjo trifatorial com parcelas subdivididas no tempo, com seis repetições por tratamento. Um segundo experimento foi realizado utilizando a técnica de pulse. Como controle foi utilizado meio de cultura MS, e para os tratamentos foi utilizado o mesmo meio acrescido de concentrações crescentes de PBZ com diferentes tempos de exposição, sendo: T0= controle (MS); T1= 1,0 mg.L-1 PBZ por 40 dias; T2= 10,0 mg.L-1 PBZ por 4 dias e T3= 100,0 mg.L-1 PBZ por 4 horas. Foram feitas as avaliações de CPA, CLF, CMR, número de raízes, massa fresca e massa seca da parte aérea, massa fresca e massa seca de raiz, massa fresca e massa seca total, contagem e caracterização estomática e avaliação anatômica do tecido radicular. O experimento foi conduzido no delineamento inteiramente casualizado totalizando quatorze repetições por tratamento. O tratamento com 1,0 mg.L-1 de PBZ por 40 dias promoveu maior desenvolvimento e vigor do sistema radicular, aumentando a espessura das raízes, podendo contribuir para a fase de aclimatização das microplântulas. Os tratamentos com pulse reduziram significativamente a parte aérea das microplântulas, não sendo recomendado na micropropagação da C. labiata. / The Species Cattleya labiata Lindley and Cattleya eldorado Linden, native to the Atlantic Forest and Amazon, respectively, are under high risk of extinction in nature, therefore, necessary to develop efficient methods of spreading their seedlings, among which highlights micropropagation. The efficiency of in vitro cultivation of orchids is associated with culture media, and especially the growth regulators. The study aimed to evaluate the influence of paclobutrazol (PBZ) in the development of in vitro microplantlets. Seedlings from germination in vitro, with 1.0 ± 0.2 cm in length, were used in the study. In the first experiment, we used to control the MS culture medium free of plant growth regulators. In the treatments, MS medium was supplemented with four concentrations of PBZ 1.0, 2.0, 4.0 and 6.0 mg L-1, with naphthaleneacetic acid (NAA) 1.0 mg L-1 associated with 6-benzylaminopurine (BAP) 1.0 mg L-1 and with the combination of 4.0 mg L-1 PBZ with 1.0 mg.L-1 NAA and 1.0 mg L-1 BAP. The morphological evaluations, number of shoots, shoot length (CPA), longest root length (CMR) and leaf blade length (CLF) were performed at the beginning of the experiment and in subcultures every 40 days during 160 days. The experimental design was completely randomized in three-factor split-plot arrangement in time, with six replicates per treatment. A second experiment was performed using the technique of \"pulse\". It was used as control MS medium, and the treatments we used the same medium plus increasing concentrations of PBZ with different exposure times, as follows: T0 = control (MS), T1 = 1.0 mg L-1 PBZ for 40 days, T2 = 10.0 mg L-1 PBZ for 4 days and T3 = 100.0 mg L-1 PBZ for 4 hours. Assessments were made CPA, CLF, CMR, number of roots, fresh and dry mass of shoots, fresh weight and dry weight of root, fresh weight and total dry matter, stomatal counting and characterization and evaluation of the anatomic root tissue. The experiment was conducted in a completely randomized a total of fourteen replicates per treatment. Treatment with 1.0 mg L-1 of PBZ for 40 days promoted further development and vigor of the root system, increasing the thickness of the roots and may contribute to the acclimatization phase of microplantlets. Treatments with \"pulse\" significantly reduced the shoot microplantlets and Its not recommended to the micropropagation of C. labiata.
58

Relações hídricas e respostas ao déficit hídrico da espécie Bauhinia forficata Link: mecanismos de manutenção do status hídrico / Water relations and responses to water deficit in Bauhinia forficata Link species: mechanisms of maintenance of water status.

Sanches, Rodrigo Fazani Esteves 10 August 2012 (has links)
O déficit hídrico decorrente da seca se estabelece quando a absorção de água pelas raízes não consegue atender as demandas da planta, entre as quais estão a fotossíntese e transpiração, essenciais ao crescimento vegetal. Para avaliar a influência de déficits hídricos de diferentes intensidades nas relações hídricas, trocas gasosas, crescimento e acúmulo de carboidratos de Bauhinia forficata Link, plantas foram cultivadas em casa de vegetação durante três meses em vasos de 20 L e submetidas aos seguintes regimes: regas diária (controle) e regas a cada 7 (7D) e 15 dias (15D) retornando as regas diárias nos regimes 7D e 15D aos 75 dias de experimento. Em intervalos quinzenais (15, 30, 45, 60, 75, 90 dias) foram avaliados a umidade do solo (Usolo), potencial hídrico foliar (wf), a fotossíntese em resposta a radiação fotossinteticamente ativa (AxPAR) para obtenção da assimilação liquida máxima (Amax) e do ponto de saturação luminoso (PARsat), área foliar total (AFT) e massas secas (MS) de folhas (MSf), caules (MSc) e raízes (MSr). Foi também coletado material vegetal para as análises bioquímicas quantitativas dos teores de açúcares solúveis totais (AST), redutores (AR), amido (S) e prolina (Pro) por métodos colorimétricos e qualitativos da composição de carboidratos solúveis neutros por HPAEC/PAD e análise de açúcares alcoóis por GC/MS. O déficit hídrico afetou as relações hídricas, fotossíntese e crescimento das plantas, sendo que os menores valores de Usolo observados nos tratamentos 7D e 15D respectivamente, coincidiram com os menores wf, Amax e acúmulo de MS. Alterações nos PARsat em resposta ao déficit hídrico foram observadas apresentando valores médios de 665, 275 e 254 mol fótons m-2 s-1 no Controle, 7D e 15D respectivamente. O retorno das regas diárias após 75 dias de experimento, promoveu a recuperação de Amax (7,8 e 9,6 mol CO2 m-2 s-1) e dos PARsat (588 e 643 mol fótons m-2 s-1) das plantas 7D e 15D respectivamente aos 90 dias, com valores maiores daqueles observados nas plantas controle (4,7 mol CO2 m-2 s-1 e 631 mol fótons m- 2 s-1), sugerindo forte dependência da fotossíntese de B. forficata à disponibilidade hídrica no solo. Os baixos teores de amido em folhas nos tratamentos 7D e 15D podem explicar a manutenção dos teores de AST semelhante ao controle, bem como, o aumento dos ASTs após o retorno das regas diárias, os quais poderiam ser prontamente utilizados na osmorregulação e concomitante retomada do crescimento das plantas. A alta detecção de mio-inositol nas análises de HPAEC/PAD sugerem que os açúcares alcoóis podem constituir grande parte dos ASTs não redutores em folhas e raízes de B. forficata. Nas raízes, os aumentos na concentração de glicerol, galactinol e galactosilglicerol detectados por GC/MS seguem o gradiente de disponibilidade hídrica dos tratamentos, indicando uma função osmorreguladora destes açúcares em B. forficata. / The water deficit caused by drought occurs when root water uptake cannot attend plant demands to maintain photosynthesis and transpiration, two essential processes for plant growth. Aiming to evaluate the influence of water deficits of different intensities on water relations, gas exchange, growth, and carbohydrate accumulation, potted plants of Bauhinia forficata Link were grown under greenhouse conditions during three months and submitted to the following water regimes: daily irrigated (control) and irrigated every 7 (7D) or 15 days (15D), recovering the daily irrigations after 75 days of the beginning of the experiment. At fortnightly intervals (15, 30, 45, 60, 75, 90 days) we evaluated soil moisture (Usolo), leaf water potential (wf), photosynthesis in response to photosynthetically active radiation (AxPAR) to obtain the maximum net assimilation (Amax) and light saturation point (PARsat), total leaf area (AFT) and dry mass (MS) of leaves (MSf), stems (MSc) and roots (MSr). Leaves and roots were also sampled for analyses of total soluble sugars (AST), reducing sugars (AR), starch (S), and free proline (Pro) by colorimetric methods. The analyses of the soluble sugar composition were carried out by HPAEC/PAD and GC/MS. The imposed water stress affected the water relations, photosynthesis, and plant growth. Decreases in Usolo values observed in the treatments 7D and 15D, respectively, coincided with the lowest wf, Amax and accumulation of MS. Changes in PARsat in response to water deficit showed mean values of 665, 275, and 254 mol photons m-2 s-1 in control, 7D, and 15D, respectively. The re-watering after 75 days led to the recovery of Amax (7.8 and 9.6 mol CO2 m-2 s-1) and PARsat (588 and 643 mol photons m-2 s-1) of plants 7D and 15D, respectively, at 90 days, with higher values than those observed in the control plants (4.7 mol CO2 m-2 s-1 e 631 mol photons m-2 s-1), suggesting a strong dependence of the photosynthesis of B. forficata of the soil water availability. The low leaf starch contents in the 7D and 15D treatments could explain the maintenance of the concentration of AST similar to control, as well as the increase in AST contents after re-watering. These sugars could be promptly used for osmoregulation and concomitant re-start of plant growth. The presence of high amounts of of myo-inositol detected by HPAEC/PAD analysis suggests that sugar alcohols can constitute the major part of non-reducing ASTs in leaves and roots of B. forficata. In roots, increases in the contents of glycerol, galactinol, and galactoglycerol detected by GC/MS indicating that these sugars can play a role in the osmoregulation of B. forficata.
59

As espécies da tribo Euglossini (Hymenoptera: Apidae) em diferentes cotas altimétricas em áreas de Mata Atlântica na região norte de Santa Catarina / The species of tribe Euglossini (Hymenoptera: Apidae) at different altitudes in areas of Atlantic Forest in northern Santa Catarina

Enderlei Dec 13 October 2015 (has links)
Reconhecida pela sua megadiversidade, mas também pelo alto nível de desmatamento e perda de espécies que vem ocorrendo nas últimas décadas, a Mata Atlântica é um dos biomas mais ameaçados do planeta, recebendo a denominação de hotspot mundial. As abelhas exercem papel fundamental para a manutenção da vegetação por meio da polinização e o conhecimento sobre a composição do táxon contribui para ações de conservação. Abelhas da tribo Euglossini podem atuar como bioindicadoras da qualidade ambiental e exercem uma estreita relação com determinadas plantas, principalmente da família Orchidaceae, sendo fundamentais para a perpetuação de muitas espécies desta família. A tribo Euglossini apresenta riqueza de espécies nas florestas tropicais decaindo em direção às latitudes altas. Este estudo propôs investigar e reconhecer a fauna de Euglossini presente na região norte do estado de Santa Catarina, no sul do Brasil, a partir de coletas mensais em seis localidades, distribuídas ao longo de um gradiente altitudinal entre o nível do mar e 800 metros, nos municípios de Joinville e São Francisco do Sul. Duas localidades são constituídas por morros remanescentes de Mata Atlântica, inseridos na malha urbana de Joinville, com extensões de aproximadamente 390 e 525 hectares. As demais localidades compõem áreas contínuas de floresta na costa litorânea e Serra do Mar. Em cada local houve um dia de coleta por mês nos períodos de setembro/2013 até abril/2014 e de setembro/2014 até abril/2015. As iscas odoríferas disponibilizadas foram: benzoato de benzila, cineol, eugenol e vanilina. Nos últimos seis meses do estudo foi testada uma nova fragrância à base de menta: o mentol. O estudo registrou 794 machos de Euglossini dos gêneros Eufriesea, Euglossa e Eulaema, distribuídos em dez espécies válidas e uma potencialmente nova. As localidades com maiores riquezas foram os remanescentes no Morro do Finder e Morro do Boa Vista, e as maiores diversidades ocorreram na Vila da Glória e Mutucas. As espécies Eufriesea violacea Blanchard 1840, Euglossa annectans Dressler 1982 e Eulaema nigrita Lepeletier, 1841 foram registradas nas seis localidades estudadas. Ef. violacea, Eg. annectans Eg. stellfeldi representaram 91,56% da comunidade amostrada, sendo 66,87% somente da primeira espécie. O cineol atraiu 299 abelhas, o eugenol 190 e vanilina 165, mas em relação à riqueza, os mais atrativos foram o benzoato de benzila, cineol e vanilina, com seis espécies cada. O mentol mostrou eficácia, atraindo 75 abelhas de quatro espécies. A distribuição das abelhas em relação a variação altitudinal demonstrou que as maiores riqueza e abundância ocorreram entre o nível do mar e 200 metros de altitude com diminuição do número de indivíduos e espécies acima desta cota. Interações entre as abelhas e oito espécies de orquídeas foram registradas a partir de polinários aderidos às abelhas. Apesar da ocupação humana no entorno dos fragmentos da área urbana, os Morros do Finder e do Boa Vista apresentaram bom estado de conservação para a comunidade de Euglossini. Novos esforços e utilização de outras metodologias podem enriquecer os dados obtidos contribuindo para uma melhor caracterização ambiental da região. A partir dos dados existentes na literatura sobre a tribo Euglossini em Santa Catarina, nota-se uma riqueza significativa nos municípios de Joinville e São Francisco do Sul. / Recognized for its megadiversity, but also the high level of deforestation and species loss that has occurred in recent decades, the Atlantic Forest is one of the most threatened biomes on the planet, getting the global name hotspot. Bees play a crucial role in the maintenance of vegetation through pollination and knowledge about the taxon composition contributes to conservation actions. The tribe Euglossini can act as bioindicators of environmental quality and exert a close relationship with certain plants, particularly the orchid family, being fundamental to the perpetuation of many species of this family. The tribe Euglossini has a species richness in tropical forests which decreases in the higher latitudes. This study aimed to investigate and identify the Euglossini fauna present in the northern state of Santa Catarina, in southern Brazil, from monthly collections in six locations distributed along an altitudinal gradient between sea level and 800 meters, in the cities of Joinville and São Francisco do Sul. Two locations are composed of remnants of Atlantic Forest hills, situated in the urban area of Joinville, with extensions of approximately 390 and 525 hectares. Other locations comprise continuous areas of forest on the coastline and Serra do Mar. At each site there was one collection day per month in the period from September / 2013 to April / 2014 and September / 2014 to April / 2015. The available scent baits were: benzyl benzoate, cineol, eugenol and vanillin. In the last six months of the study a new mint-based fragrance was tested : menthol. The study recorded 794 Euglossini males of the genera Eufriesea, Euglossa and Eulaema, distributed in ten valid species and one potentially new species. The localities with the greatest richness were in Morro do Finder and Morro do Boa Vista, and the largest diversity occurred in the Vila da Glória and Mutucas. The species Eufriesea violacea Blanchard 1840, Euglossa annectans Dressler 1982 e Eulaema nigrita Lepeletier, 1841 were recorded in the six studied locations. Ef. violacea, Eg. annectans and Eg. stellfeldi represented 91.56% of the sampled community, with the first species making up 66.87% of that figure. The cineole attracted 299 bees, eugenol 190 and vanillin 165, but in relation to richness, the most attractive were the benzyl benzoate, cineole and vanillin, with six species each. The menthol was effective, attracting 75 bees from four species. The distribution of bees in relation to altitudinal variation showed that the greatest richness and abundance occured between sea level and an altitude of 200 metres, with a decrease in the number of individuals and species above this altimetry quota. Interactions between bees and eight species of orchids were recorded from pollinaria adhered to the bees. Despite the surrounding human occupation of urban fragments, Morros Finder and Boa Vista showed good conditions for the community of Euglossini. New efforts and using other methodologies can enrich the data, contributing to a better environmental characterization of the area. From the literature data on the tribe Euglossini in Santa Catarina, there is a significant richness in the cities of Joinville and São Francisco do Sul.
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Delimitação de espécies e diversidade genética no complexo Cattleya coccinea Lindl. e C. mantiqueirae (Fowlie) van den Berg (Orchidaceae) baseada em marcadores  moleculares ISSR / Species Delimitation and genetic diversity in Cattleya coccinea Lindl. and C. mantiqueirae (Fowlie) van den Berg complex (Orchidaceae) based on ISSR molecular makers

Rodrigues, Jucelene Fernandes 19 January 2011 (has links)
As orquídeas são a maior família das plantas monocotiledôneas, sendo o Brasil um dos países contém grande diversidade de espécies. As orquídeas são, em sua maioria, alógamas e possuem mecanismos sofisticados para evitar a autopolinização. Os insetos são os agentes polinizadores mais comuns, mas também podem ser polinizados por aves como beija-flores. Tradicionalmente as espécies Cattleya coccinea e C. mantiqueirae tem sido reconhecidas como distintas de acordo com caracteres morfológicos, distribuição geográfica e época de floração. Esses critérios, entretanto, não permitem a identificação clara de espécies, uma vez que muitos indivíduos apresentam morfologia e fenologia intermediárias. Nesse contexto, esse estudo tem como objetivo contribuir para o conhecimento taxonômico e evolutivo de orquídeas brasileiras do gênero Cattleya. Especificamente, propõe-se rever a atual delimitação entre as espécies C. coccinea e C. mantiqueirae e caracterizar a diversidade genética entre e dentro de populações dessas espécies a partir de marcadores moleculares ISSR. Para testar se a atual delimitação de espécies corresponde a linhagens filogenética distintas, foram realizadas coletas em seis localidades da região Sudeste. Foram testados 20 iniciadores ISSR, dos quais 13 foram otimizados para obtenção de dados. Os géis de ISSR obtidos foram utilizados para construção de uma matriz binária representando a presença/ausência de fragmentos amplificados. A matriz contendo 173 indivíduos e 295 caracteres foi analisada com algoritmo de neighbor-joining e o critério de parcimônia máxima para obtenção de hipóteses filogenéticas. Os resultados indicam que as espécies tradicionalmente reconhecidas, C. coccinea e C. mantiqueirae, não constituem grupos monofiléticos e, portanto, não podem ser reconhecidas como espécies distintas de acordo com o conceito filogenético de espécies. Os resultados também apontam que as populações amostradas constituem grupos monofiléticos com altos valores de confiança e que o complexo C. coccinea-C. mantiqueirae não constitui um grupo monofilético. O parafiletismo do grupo é determinado pela posição da população de Lima Duarte/MG, que constitui um clado irmão da espécie C. brevipedunculata (ocorrente na Serra do Espinhaço) e C. wittigiana (restrita ao Estado do Espírito Santo). Os resultados de análises de genética de populações corroboram com os resultados da análise filogenética e indicam que as populações possuem baixos índices de diversidade genética entre indivíduos e que a maior diversidade encontra-se entre populações. Por serem plantas com alto valor ornamental e sofrerem com ações antrópicas constantes, esse estudo foi de fundamental importância para permitir estratégias viáveis para a manutenção e conservação da diversidade genética dessas populações de orquídeas. / Orchids represent the largest family of monocots, with great diversity of species in Brazil. These plants are generally allogamous and bear sofisticated mechanisms to avoid self-pollination. Insects are by far the most common pollinators, but birds (i.e hummingbirds) may also be important. Within Cattleya, the species C. coccinea and C. mantiqueirae have been distinguished by morphological characters, geographical distribution and flowering period. Such criteria, however, do not allow a clear identification of species, since many specimens show intermediate morphological and phenological variation. The goal of this study is to contribute to the understanding of taxonomical and evolutionary aspects of Brazilian orchids, especially within the genus Cattleya. In order to achieve that I revised current species limits within the C. coccinea-C. mantiqueirae species complex. The study was based on phylogenetic and genetic diversity analyses among and within populations considering ISSR molecular markers. Six populations from Southeastern Brazil were considered. I tested 20 ISSR primers, of which 13 were used in this study. Presence/absence of fragments visualized in agarose gels were used to built a binary matrix. The analyses considered 173 individuals and 295 caracters (fragments). Phylogenetic analyses were performed according to distance (neigbor-joining) and parsimony criteria. According to the results, the species C. coccinea and C. mantiqueirae do not constitute monophyletic groups and, therefore, cannot be recognized as distinct according to the phylogenetic species criterion. Also the C. coccinea-C. mantiqueirae species complex is paraphyletic considering the closely related species C. brevipedunculata (from Serra do Espinhaço) and C. wittigiana (from Espírito Santo State). The population of Lima Duarte/MG is phylogenetically more closely related to such species than to other populations of C. coccinea and C. mantiqueirae. On the other hand, the studied populations comprise strong monophyletic groups. Population genetics analyses agree with phylogenetic results. All populations show low diversity indices among individuals. Also, the greatest portion of genetic diversity was found between populations. Orchids belonging to the C. coccinea-C. mantiqueirae species complex are high ornamental species, with great anthropogenic pressure. For this reason this study was important to allow conservation strategies to maintain and monitor genetic and morphological diversity of populations.

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