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1.
Am J Bot ; 110(6): e16194, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37283436

RESUMEN

PREMISE: Distyly is a condition in which individual plants in a population express two floral morphs, L- and S-morph, characterized by reciprocal placements of anthers and stigmas between morphs. The function of distyly requires that pollinators collect pollen from L- and S-morphs on different parts along their bodies to then deposit it on the stigmas of the opposite morph, known as legitimate pollination. However, different pollinator groups might differ in the ability to transfer pollen legitimately. METHODS: We investigated patterns of pollen pickup along the body of different functional groups (hummingbirds and bees) using preserved specimens to analyze their role in the reproductive success of Palicourea rigida. We measured pollen deposition on the body of pollinators, on stigmas, and fruit production after a single visit. RESULTS: Pollen from L- and S-flowers appeared segregated on different body parts of the hummingbird and bee used in the study. S-pollen was deposited primarily on the proximal regions (near the head), and L-pollen was placed in the distal regions (tip of the proboscis and bill). Hummingbirds were more efficient at legitimate pollination than bees, particularly to S-stigmas. However, fruit formation after single visits by both pollinators was similar. CONCLUSIONS: The morphology of distylous flowers allows the segregated placement of L-and S-pollen on different body parts of the animal specimens used, facilitating the promotion of legitimate pollen transfer, an observation consistent between the two functional pollinator groups. Also, the results show that full fruit set requires more than one visit.


Asunto(s)
Mariposas Diurnas , Rubiaceae , Abejas , Animales , Frutas , Reproducción , Polinización , Polen , Rubiaceae/anatomía & histología , Flores/anatomía & histología , Aves
2.
Gigascience ; 112022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35639882

RESUMEN

BACKGROUND: Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. RESULTS: Here we present a vocabulary of terms and a data model for sharing plant-pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant-pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant-pollinator interactions. CONCLUSIONS: The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant-pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant-pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of terms.


Asunto(s)
Ecosistema , Polinización , Animales , Biodiversidad , Filogenia , Estándares de Referencia
3.
Am J Bot ; 107(6): 910-922, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32462680

RESUMEN

PREMISE: Distylous species possess two floral morphs with reciprocal positioning of stigmas and anthers that is hypothesized to promote disassortative pollination. Theoretical models predict equal morph frequencies, but many populations depart from the expected 1:1 ratio, a pattern that often correlates with asymmetric mating between morphs and/or presence of a weak incompatibility system. Variation in reciprocity can also affect the likelihood of disassortative pollination and, hence, reproductive fitness. METHODS: We described variation in incompatibility systems and morph ratio in four Erythroxylum species to test if greater deviations from 1:1 ratios occur in populations of self-compatible species. Using adaptive inaccuracy, we described upper and lower organ reciprocity in species and populations and assessed the relationship of reciprocity to population means and coefficients of variation for fruit set to test if reciprocity could predict female reproductive success. RESULTS: Morphs occurred in 1:1 ratios in most populations of three Erythroxylum species with distylous self-incompatibility. In self-compatible E. campestre populations showed an excess of the long-styled morph, the short-styled morph, or were monomorphic for the short-styled morph. We detected deviations from reciprocity, with total inaccuracy ranging between 9.39% and 42.94%, and inaccuracy values were lowest in low organs. Across populations, we found a positive relationship between inaccuracy and the coefficient of variation of fruit set. CONCLUSIONS: Erythroxylum species showed variation in the distylous syndrome, with changes in the incompatibility system that corresponded with deviations from 1:1 morph ratio, and variation in reciprocity that correlated with variation in female reproductive fitness.


Asunto(s)
Flores , Polinización , Fenotipo , Reproducción
4.
Rev. bras. farmacogn ; 29(4): 491-494, July-Aug. 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1042278

RESUMEN

Abstract Bioassay-guided fractionation of Bowdichia virgilioides Kunth, Fabaceae, extracts has led to the isolation of cathepsin V inhibitors. The investigation of the hexane and ethyl acetate extracts allowed the characterization of eleven compounds: lupeol, lupenone, β-sitosterol and stigmasterol in mixture, trans p-coumaric acid ester derivative, syringaresinol, bowdenol, 8-methoxycoumestrol, 3,4-hydroxy-7-methoxyisoflavone, 7,3′-dihydroxy-4′-methoxyisoflavone, and 5,4′-dihydroxy-7′-methoxyisoflavone. Structures of compounds were stablished by 1D and 2D NMR, and MS experiments. Among the isolated compounds, trans p-coumaric acid ester derivative and 8-methoxycoumestrol showed significant inhibition on cathepsin V, which is up to now unexplored.

5.
Biosci. j. (Online) ; 31(3): 890-907, may./jun. 2015.
Artículo en Portugués | LILACS | ID: biblio-963898

RESUMEN

Estudos que envolvem aspectos da polinização e sistema reprodutivo em Angiospermas são fundamentais para a compreensão de diversos processos ecológicos e evolutivos. Desta forma, foi realizada uma revisão bibliográfica com o objetivo de compilar informações sobre a polinização e o sistema reprodutivo encontrados na família Acanthaceae Juss. no Brasil. Um total de 30 estudos, com 31 espécies, fizeram parte da presente revisão. Quanto a distribuição geográfica e domínio fitogeográfico, a região Sudeste (50%) e o bioma Mata Atlântica (56,7%) apresentaram a maior proporção de estudos. Quatro síndromes de polinização foram registradas, sendo elas: troquilofilia, melitofilia, psicofilia e quiropterofilia, sendo a troquilofilia predominante (79,31% das espécies). Consequentemente, beija-flores foi o grupo mais comum de visitantes florais, interagindo com 86,2% das espécies, sendo Phaethornis pretrei o principal beija-flor visitante. Outros grupos de visitantes também foram registrados, como abelhas (segundo principal grupo), borboletas, morcegos, mariposas, vespas, moscas e besouros. Das 17 espécies estudadas no Brasil quanto ao sistema reprodutivo, todas apresentaram flores andróginas, sendo 16 espécies (94,1%) autocompatíveis. Fatores intrínsecos como a hercogamia e a dicogamia foram comuns em espécies de Acanthaceae, constituindo mecanismos que minimizam a interferência entre as funções masculina e feminina em flores andróginas e maximizam a polinização cruzada. Aproximadamente, 41,2% das espécies exibiram autopolinização espontânea, isto é, produção de frutos sem a necessidade de agentes polinizadores. Estratégias reprodutivas como a cleistogamia e a agamospermia também foram registradas nas espécies de Acanthaceae no Brasil. Contudo, mais estudos a respeito da polinização e sistema reprodutivo com acantáceas brasileiras precisam ser desenvolvidos, para ampliar a amostragem e, então subsidiar mais as estimativas desta revisão.


Studies involving aspects of pollination and breeding system in Angiosperms are fundamental in understanding many ecological and evolutionary processes. Thus, a literature review was conducted to aim of compiling information on the pollination and reproductive system in species of Acanthaceae Juss. in Brazil. A total of 30 studies, count 31 species, were part of this review. Regarding geographical distribution of studies, the Southeast Brazil (50%) and Atlantic Forest biome (56.7%) had the higher proportion of studies. Four pollination syndromes were recorded: trochilophily, melittophily, psycophily, and chiropterophily, in which trochilophily was predominant (79.31% of species). Consequently, hummingbirds were the most common flower visitors, interacting with 86.2% of the species, and Phaethornis pretrei was the main hummingbird visitor. Other groups of visitors were also recorded, such as bees (second main group, 34.5%), butterflies, bats, moths, wasps, flies and beetles. From the 17 species studied in Brazil about the reproductive system, all have androgynous flowers and 16 species (94.1%) selfcompatibility. Intrinsic factors such as herkogamy and dichogamy were common in species of Acanthaceae, constituting mechanisms that minimize interference between male and female functions in androgynous flowers and maximize cross-pollination. Approximately 41.2% of species presented spontaneous self-pollination, i.e. production of fruits without the need of pollinators. Reproductive strategies such as cleistogamy and agamospermy were also recorded in species of Acanthaceae in Brazil. However, more studies on the pollination and reproductive system with species of Acanthaceae in Brazil need to be developed to expand the sampling and then support better the estimates of this review.


Asunto(s)
Revisión , Magnoliopsida , Acanthaceae , Polinización
6.
J Food Prot ; 76(11): 1892-901, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24215693

RESUMEN

Sitophilus zeamais (Coleoptera: Curculionidae) and Spodoptera frugiperda (Lepidoptera: Noctuidae) are important economic pests of corn, Zea mays (Poaceae). Psychotria spp. (Rubiaceae) plants are rich in secondary metabolites that could be toxic against such pests. We have screened extracts from four species of Psychotria abundant in the Cerrado (Savannah-type) biome of Brazil for the toxicity to two insects. We found that extracts from leaves and stems had significant effects on the hatching rate, parameters of caterpillar body (weight and length and width of head capsule), repellency, and mortality of these two pests, although the effects varied according to the Psychotria species and plant source (stem or leaf). Extracts of the stems of Psychotria hoffmannseggiana and of Psychotria capitata were more toxic to S. zeamais and the stems of Psychotria goyazensis to S. frugiperda; therefore, such extracts could have the potential for use in integrated pest management schemes.


Asunto(s)
Insecticidas/farmacología , Psychotria/química , Spodoptera/crecimiento & desarrollo , Gorgojos/crecimiento & desarrollo , Zea mays/parasitología , Animales , Brasil , Conservación de Alimentos/métodos , Hojas de la Planta/química , Tallos de la Planta/química
7.
Biosci. j. (Online) ; 29(5-Supplement 1): 1708-1720, nov. 2013. tab, ilus
Artículo en Portugués | LILACS | ID: biblio-967410

RESUMEN

O objetivo foi avaliar a fenologia reprodutiva e as síndromes de polinização e dispersão de um subbosque de Mata Seca Semidecídua. O estudo foi realizado na cidade de Catalão-GO, de maio de 2010 a maio de 2011, no Parque Municipal do Setor Santa Cruz, um fragmento de 29 hectares. A coleta dos dados fenológicos foi semanal utilizando um transecto de 1000 m. Para as síndromes, foi observado à morfologia de flores e frutos, e estes dados foram relacionados aos de fenologia. A floração teve maior índice (43,13%) em dezembro de 2010 (chuva) e a frutificação manteve índices de 25 a 30% na maior parte do ano. Acanthaceae apresentou o maior índice de floração em maio de 2010 e fevereiro de 2011; Piperaceae em outubro de 2010 e Rubiaceae em dezembro 2010. A frutificação em Acanthaceae ocorreu durante a seca e inicio das chuvas, com maior índice em outubro de 2010, Piperaceae na estação das chuvas e inicio da seca, com pico em maio de 2011, e em Rubiaceae ocorreu durante 11 meses, com pico em março de 2011. Duas espécies de Acanthaceae e uma de Piperaceae não apresentaram frutificação, já a fenofase de floração foi observada nessas espécies. Foram identificadas três síndromes de polinização, sendo estas melitofilia (pico de intensidade em outubro de 2010), psicofilia (janeiro de 2011) e ornitofilia (maio de 2010). As síndromes de dispersão foram ornitocoria (dois picos, um em julho de 2010 e outro em maio de 2011) e anemocoria (pico em outubro de 2010). A presença de espécies em floração e/ou frutificação ao longo do ano pode contribuir para a dinâmica e permanência da comunidade estudada, pois essas espécies auxiliam na manutenção de abelhas e aves no fragmento, importantes vetores de polinização e dispersão. Levando em consideração que o Cerrado vem sofrendo um intenso impacto ambiental e a área de estudo ser um fragmento localizado dentro de um perímetro urbano, a sua conservação torna-se de grande importância, apesar de sua pequena área, devido os importantes processos ecológicos que ali existem.


The objective was to identify the reproductive phenology and the pollination and dispersal syndromes of understory species of Semi-deciduous Dry Forest. The work was carried out from May 2010 to May 2011 in a forest fragment, about 29 hectares, localized in Catalão city, Goiás State, Brazil. The phenological phases were observed weekly along a transect at 1000m. Pollination and dispersion syndromes were determined through literature data, and theses data were linked to phenology. The flowering proportion reached the peak (43,13%) in December 2010 (rainy) and fruiting (30%) in September 2010 (dry). Acanthaceae flowering peak in May 2010 and February 2011; Piperaceae peaked in October 2010 and Rubiaceae in December 2010. Fruiting in the Acanthaceae occurred during the dry period and the beginning of the rainy season, with the highest incidence in October 2010, Piperaceae reached their peak in May 2011, while in the Rubiaceae, it went on for 11 months, with the highest incidence being in March 2011. Two Acanthaceae and one Piperaceae species not fruited, but all species presented flowering. Pollination syndromes found were Ornithophily, peaking in May 2010, Melittophily, in October 2010, and Psycophily, in January 2011. Dispersal syndromes found were Anemochoric, with a higher incidence in October 2010, and Ornithocoric with two peaks, one in July 2010 and other in May 2011. The year-long presence of flowering and/or fruiting species contributes to the survival and dynamics of the community studied, because these species play an important role maintaining bees and birds in the fragment, which are important vectors of pollination and dispersal, respectively. Considering the rapid loss of the Cerrado vegetation in recent times and the study site to be a fragment localized inside the urban environment, the conservation of the green area becomes important, regardless of its small size, due to the important ecological processes that lie therein, as portrayed in this study.


Asunto(s)
Polinización , Dispersión de las Plantas , Reproducción , Bosques
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