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1.
Plant Biol (Stuttg) ; 26(2): 157-165, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38192089

RESUMO

Crop-pollinator interactions are essential for world food security. Studying crop pollination from a network approach allows identification of target pollinators for conservation and management, and gaps in our knowledge. Solanaceae represents the third highest ranked family based on economic value, and its production is highly improved by animal pollination. This study aimed to integrate global data on solanaceous crop pollination and analyse the interaction patterns using a meta-network approach. Our questions were: (i) how are interactions structured and what are the structuring roles of species; and (ii) what are the main gaps in our knowledge? Data were obtained through a systematic review of the main scientific databases. The network structure was described using connectivity and modularity calculations, and the role of species using centrality metrics. The 251 pollinator species reported were in seven orders, mainly Hymenoptera (84.9%). The generalists Bombus and Apis species were the most common pollinators. The meta-network was modular, and all modules mostly included bees. Most species were peripherals, around 12% were connectors, and there were no module hubs. Apis mellifera was the only network hub (supergeneralist). The most important pollinators are the most managed pollinators worldwide; however, many native species play a role in structuring the meta-network. Main gaps include species of importance to pepper pollination, lack of species-specific identification, and the need for more robust experimental studies evaluating the pollination efficiency of native, manageable bees.


Assuntos
Solanaceae , Abelhas , Animais , Produtos Agrícolas , Polinização , Especificidade da Espécie
7.
Plant Biol (Stuttg) ; 23(6): 923-930, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34532942

RESUMO

Pollination is provided by biodiversity and maintains global food production. We investigated the effects of vegetation cover on the abundance of floral visitor and vine (Vitis labrusca Raf.) production. We expected an increase in both floral visitor frequencies and vineyard yields with an increase in native vegetation cover in the landscape. We also investigated different scenarios of visitor abundance with and without honeybees (Apis mellifera L.). We surveyed floral visitors from ten vineyard plots with different native cover surrounding them and related both visitors and native vegetation to fruit set. Considering some of these vineyards, we compared physical and chemical traits of berries to understand how they vary according to native vegetation. Floral visitor abundance was positively related to native vegetation cover. However, considering only native bee abundance, we found a dual (hyperbolic) response. Apis mellifera (L.) Africanized was the most abundant species and had the highest number of interactions; however, when removed from the network analysis, the relationship between vineyards and native bees became more specialized. The fruit size and mass of berries differed among vineyards, as did some chemical traits related to commercial quality of fruits, such as soluble solids, pH and flavonoids. Vineyards surrounded by intermediate areas of native vegetation present a balance between resource availability from vineyards and native vegetation. Apis and non-Apis (such as flies and small bees) floral visitors, known to have different effects on vine pollination, could hypothetically provide variation in vine production and quality. Considering a near 20% native vegetation increment, there was an enhancement, on average, of ten-fold more berries per bunch, the changing physical and chemical fruit traits by vegetation increment could also increase the aggregate value of vines and the value of pollination services in the economy.


Assuntos
Abelhas , Frutas , Polinização , Vitis , Animais , Biodiversidade , Dípteros , Flores
8.
Plant Biol (Stuttg) ; 21(1): 142-149, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30216618

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 , Temperatura
9.
Plant Biol (Stuttg) ; 20(4): 797-801, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29573080

RESUMO

Monomorphic enantiostylous species produce flowers with a displacement of the style to the left (L) or right (R) on the same individual, and may exhibit different dynamics for the production of these floral types, which may influence levels of selfing. We investigated the production dynamics of L and R floral types in seven species and a variety of monomorphic enantiostylous species of the genera Senna and Chamaecrista. Our hypothesis was that most species present similar proportions of floral morphs each day. Individuals were classified daily over a period of 7 days according to the functional status, i.e. the proportion of floral morphs as functionally L, R or reciprocal (REC, i.e. similar proportions of the two floral morphs), and also according to the number of consecutive days in which they exhibited the same functional status. All species presented low daily flower production. Most species had individuals classified as functionally R, L and REC, and tend to repeat the same functional status over a few days, although they may change functional status during the flowering period. All species exhibited individuals that were classified as functionally reciprocal when both the daily and total number of flowers produced over 7 days was considered. The occurrence of different functional status has not yet been reported in the literature for enantiostylous species. The distinct strategies observed in the dynamics of floral morph production seemed likely to minimise geitonogamy and to favour cross-pollination between individuals (xenogamy).


Assuntos
Fabaceae/fisiologia , Flores/fisiologia , Brasil , Fabaceae/anatomia & histologia , Flores/anatomia & histologia
11.
Transplant Proc ; 49(1): 169-171, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28104128

RESUMO

The combined liver-kidney transplantation (cLKT) is the procedure of choice for patients with end-stage liver and kidney disease. In cLKT we can usually accommodate the grafts in two different ways, varying the kidney placement. The retroperitoneal kidney implant has some advantages, such as the easy access or avoiding vascular complications. We propose a new single incision, not yet reported, maintaining an extraperitoneal kidney, with excellent surgical field for cLKT and possible reduction of the impact of wound complications.


Assuntos
Carcinoma Hepatocelular/cirurgia , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Cirrose Hepática/cirurgia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/métodos , Carcinoma Hepatocelular/complicações , Hepatite C Crônica/complicações , Humanos , Falência Renal Crônica/complicações , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Espaço Retroperitoneal/cirurgia , Resultado do Tratamento
12.
Plant Biol (Stuttg) ; 19(2): 115-122, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27796070

RESUMO

The characteristics of petal epidermal conical cells affect the quality of the signals perceived by various pollinators. This study aimed to identify variations in micromorphological characteristics of flower petals and their relationship to melittophily, ornithophily and chiropterophily pollination systems. The petals of 11 species were analysed using scanning electron microscopy and optical microscopy and the micromorphological traits were described, measured and compared using Tukey's test, PCA and cluster analysis. Unlike chiropterophily, all melittophilous and some ornithophilous species possessed adaxial epidermal conical cells. Cluster grouping separated chiropterophilous flowers from melittophilous and ornithophilous. PCA analysis showed that the two morphometric profile of conical cells was the attribute that most strongly influenced the grouping of species. When considering the data set of the three pollination systems, melittophilous and ornithophilous plants were more similar to each other than they were to chriopterophilous species. The distance between conical cell apices is an important parameter in interactions with pollinators. This study facilitated recognition of smoothing pollinator resource access through petal micromorphological characteristics. Further research regarding the biometry of micromorphological traits related to pollination is required.


Assuntos
Flores/anatomia & histologia , Plantas/anatomia & histologia , Polinização , Animais , Abelhas/fisiologia , Aves/fisiologia , Quirópteros/fisiologia , Flores/genética , Flores/fisiologia , Fenótipo , Epiderme Vegetal/genética , Epiderme Vegetal/fisiologia , Plantas/genética , Pólen/anatomia & histologia , Pólen/genética , Pólen/fisiologia
13.
Braz. j. biol ; 76(4): 975-982, Oct.-Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-828090

RESUMO

Abstract Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety. The phonological results, including knowledge of growing degree days, are important to the planning of cultures at the study site and in other regions that have similar climatic conditions and make it possible to pre-determine the harvest.


Resumo Fenologia e biologia reprodutiva de espécies cultivadas são importantes para a compreensão dos requerimentos para a produção de frutos e sementes, bem como para o manejo de polinizadores. O presente estudo objetivou caracterizar a fenologia, a biologia reprodutiva e a exigência térmica (graus-dias) da videira “Isabel” (Vitis labrusca) no nordeste do Brasil, durante janeiro/2011 (P1), Agosto/2011 (P2), Abril/2012 (P3) e Agosto/2012 (P4). Analisamos a duração (dias) dos estádios fenológicos poda (PO), gema-algodão (GA), brotamento (BR), aparecimento da inflorescência (AI), florescimento (FL), início da maturação (IM) e colheita (CO). Analisamos a biologia floral, o sistema sexual e o sistema reprodutivo. As exigências térmicas foram obtidas em termos de graus-dia (GD) necessários para atingir os subperíodos PO-BR, BR-FL e FL-CO. A duração do ciclo foi de 116, 125, 117 e 130 dias para as épocas P1, P2, P3 e P4 respectivamente, sendo o número de dias de colheita semelhantes no período seco (P1 e P3) e chuvoso (P2 e P4). Todos os períodos analisados foram mais curtos do que aqueles observados em outras regiões do Brasil, o que pode ser atribuído à temperatura média e ao metabolismo de carboidratos. As flores são verdes, hermafroditas, com odor almiscarado, baixa viabilidade polínica e autógama. A temperatura base de 10ºC foi considerada a mais adequada para os subperíodos e tem sido documentada para outras variedades de uva no Brasil; portanto, a temperatura foi também a mais adequada para os ciclos, apresentando um desvio padrão menor (0,119; 0,147; 0,156 e 0,153 para P1, P2, P3 e P4, respectivamente), comparado com uma temperatura base de 12ºC (0,122; 0,158; 0,165 e 0,160 para P1, P2, P3 e P4, respectivamente). O maior é o menor GDD observado foram 1972,17 e 1870,05, respectivamente. Os resultados fenológicos, incluindo o conhecimento dos graus dias, são importantes para o planejamento de culturas no local e em outras regiões com condições climáticas semelhantes, tornando possível pré-determinar a colheita.


Assuntos
Vitis/crescimento & desenvolvimento , Reprodução , Sementes/crescimento & desenvolvimento , Temperatura , Brasil , Flores/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento
14.
Braz J Biol ; 76(4): 975-982, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27191458

RESUMO

Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine 'Isabel' (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety. The phonological results, including knowledge of growing degree days, are important to the planning of cultures at the study site and in other regions that have similar climatic conditions and make it possible to pre-determine the harvest.


Assuntos
Vitis/crescimento & desenvolvimento , Brasil , Flores/crescimento & desenvolvimento , Frutas/crescimento & desenvolvimento , Reprodução , Sementes/crescimento & desenvolvimento , Temperatura
15.
Carbohydr Polym ; 136: 274-81, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26572356

RESUMO

Fructo-oligosaccharides (FOS) obtained by fermentation of sucrose may be purified at large-scale by continuous chromatography (Simulated Moving Bed: SMB). In order to improve the efficiency of the subsequent SMB purification, the optimization of the fermentative broth composition in salts and sugars was investigated. Fermentations conducted at reduced amount of salts, using Aureobasidium pullulans whole cells, yielded 0.63 ± 0.03 g of FOS per gram of initial sucrose. Additionally, a microbial treatment was proposed to reduce the amount of small saccharides in the mixture. Two approaches were evaluated, namely a co-culture of A. pullulans with Saccharomyces cerevisiae; and a two-step fermentation in which FOS were first synthesized by A. pullulans and then the small saccharides were metabolized by S. cerevisiae. Assays were performed in 100mL shaken flasks and further scaled-up to a 3 L working volume bioreactor. Fermentations in two-step were found to be more efficient than the co-culture ones. FOS were obtained with a purity of 81.6 ± 0.8% (w/w), on a dry weight basis, after the second-step fermentation with S. cerevisiae. The sucrose amount was reduced from 13.5 to 5.4% in total sugars, which suggests that FOS from this culture broth will be more efficiently separated by SMB.


Assuntos
Ascomicetos/metabolismo , Biotecnologia/métodos , Fermentação , Frutose/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , Saccharomyces cerevisiae/metabolismo , Ascomicetos/citologia , Técnicas de Cocultura , Saccharomyces cerevisiae/citologia
16.
Plant Biol (Stuttg) ; 17(3): 740-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25363754

RESUMO

Species of the subtribe Cassiinae present a wide diversity of floral types. Until recently it was considered that this diversity did not extend to their reproductive mechanisms. However, studies have recorded some variations in the enantiostylous pattern in this plant group. This study aims to investigate the morphological and functional variations of enantiostyly in species of the subtribe Cassiinae. Additionally, it proposes the recognition of enantiostylous types (ET) based on pollen deposition and capture mode. Morphological data were collected in fresh and fixed (alcohol 70%) buds and flowers, and also using photos and rehydrated material from herbarium sheets, for a total of 59 species. The parameters used to establish the ETs were pollination type, nature of pollen deposition on the pollinator body, deposition type, number of petals involved in pollen deposition, and pollen pathway. Morpho-functional features allowed the recognition of seven enantiostylous types (Flexuosa, Cana, Macranthera, Martiana, Amiciella, Repens and Ramosa) that present several levels of complexity. The type Ramosa was the most common and the Cana type was the least common. The types Repens, Martiana and Flexuosa do not have reciprocal pollen deposition, thus species with these types may be considered atypical. The groups resulting from similarity analysis partially coincide with the clades proposed in phylogenetic studies of Cassiinae. The recognition of functional ETs is important for understanding the evolution of reproductive strategies of Cassiinae species, and indicates an interesting line of investigation of enantiostyly in other plant groups.


Assuntos
Evolução Biológica , Fabaceae/anatomia & histologia , Flores/anatomia & histologia , Fenótipo , Filogenia , Polinização , Fabaceae/genética , Pólen , Reprodução
17.
Arq. bras. med. vet. zootec ; 66(1): 1-6, fev. 2014. tab
Artigo em Português | LILACS | ID: lil-703998

RESUMO

No Brasil existem poucos estudos sobre a ocorrência da infecção pelo vírus da imunodeficiência felina (FIV), assim como a determinação dos subtipos circulantes, o que é indispensável para o desenvolvimento de vacinas e novos testes diagnósticos. O presente trabalho investigou a ocorrência da infecção pelo FIV entre os anos de 2010 e 2011 em gatos domésticos submetidos a atendimento clínico na cidade de Pelotas e região. Amostras de sangue total de 70 animais, incluindo suspeitos (28) ou não suspeitos (42) da infecção pelo FIV, foram submetidas à reação de PCR nested. Os resultados indicaram uma frequência de infecção de 15,7% (11/70) e a análise dos fatores associados (sexo, idade e condição clínica) evidenciou uma maior ocorrência em gatos com idade superior a 10 anos e acometidos por infecções crônicas e recidivantes. Oito amostras positivas na PCR nested foram submetidas a sequenciamento genômico e somente o subtipo B foi detectado na região estudada.


In Brazil there are few studies on the occurrence of the feline immunodeficiency virus (FIV) infection and its subtypes, which are essential for the development of vaccines and new diagnostic tests. The present study investigated the occurrence of the FIV infection between 2010 and 2011 in domestic cats submitted to medical attendance in the city of Pelotas and nearby area. Total blood samples of seventy cats, suspected (28) or not (42) of infection by FIV were analyzed by nested PCR in order to perform a diagnosis. The results pointed to a FIV infection frequency of 15.7% (11/70) and the analysis of the risk factors related to infection (sex, age and clinical condition) evidenced a greater occurrence in cats up to 10 years of age with chronic and recurrent infections. Eight samples found positive by nested PCR were submitted to DNA sequencing indicating that only the subtype B was detected in the studied region.


Assuntos
Animais , Gatos , Animais Domésticos , Reação em Cadeia da Polimerase , Vacinas/farmacologia , Gatos/classificação
19.
Plant Biol (Stuttg) ; 15(2): 369-75, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23127184

RESUMO

Enantiostyly is a form of reciprocal herkogamy, in which floral morphs present reciprocal differences in the position of sexual elements, and occurs in monomorphic and dimorphic forms. This polymorphism maximises cross-pollination and reduces self-pollination, being very common within the subtribe Cassiinae (Fabaceae). Nevertheless, few studies have investigated the functionality of enantiostyly, particularly in this plant group. The present study aimed to investigate enantiostyly and its functionality in Chamaecrista ramosa, a monomorphic enantiostylous shrub, in an area of coastal vegetation in northeast Brazil. Pollen deposition and capture on the body of floral visitors, the relationship of these data with floral biology and breeding system, and morph ratio were evaluated. Pollen deposition and capture occurred in specific sites of the floral visitor body, showing the functionality of enantiostyly. The floral architecture, associated with the floral visitor behaviour, resulted in indirect pollen deposition on the floral visitor body. This occurred through a loop made by the pollen upon the inner petal surface, similar that generally reported for other Cassiinae. Chamaecrista ramosa is self-compatible, although no fruit set was observed through spontaneous self-pollination. The occurrence and number of floral morphs was similar within clumps. Enantiostyly seems to be advantageous for this species, as it results in efficient pollen capture and deposition, reduces the chances of autogamy and maximises intermorph pollen flow.


Assuntos
Cruzamento , Fabaceae/anatomia & histologia , Flores/anatomia & histologia , Pólen/fisiologia , Animais , Abelhas/fisiologia , Tamanho Corporal , Brasil , Fabaceae/fisiologia , Flores/fisiologia , Herbivoria/fisiologia , Movimento/fisiologia , Polinização , Autofertilização/fisiologia , Especificidade da Espécie
20.
Genet Mol Res ; 11(3): 2045-50, 2012 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-22911588

RESUMO

Isochromosome 17q is a relatively common karyotypic abnormality in medulloblastoma, gastric, bladder, and breast cancers. In myeloid disorders, it is observed during disease progression and evolution to acute myeloid leukemia in Philadelphia-positive chronic myeloid leukemia. It has been reported in rare cases of myelodysplastic syndrome, with an incidence of 0.4-1.57%. Two new agents have been approved for treatment of myelodysplastic syndrome/chronic myelomonocytic leukemia. These are the hypomethylating agents, 5-azacytidine and decitabine, recommended by consensus guidelines for high-risk myelodysplastic syndrome patients not eligible for hematopoietic stem cell transplantation. We present a case of chronic myelomonocytic leukemia with normal cytogenetics at diagnosis treated with decitabine (with good response); however, the patient evolved to acute myeloid leukemia with i(17q) shortly after suspending treatment. To the best of our knowledge, this is the first report of acute myeloid leukemia with myelodysplasia-related changes with i(17q) after the use of a hypomethylating agent.


Assuntos
Azacitidina/análogos & derivados , Cromossomos Humanos Par 17/genética , Metilação de DNA/genética , Isocromossomos/genética , Leucemia Mieloide Aguda/induzido quimicamente , Leucemia Mieloide Aguda/genética , Síndromes Mielodisplásicas/induzido quimicamente , Azacitidina/efeitos adversos , Transformação Celular Neoplásica/patologia , Decitabina , Evolução Fatal , Humanos , Cariotipagem , Leucemia Mieloide Aguda/complicações , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/genética
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