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1.
Ciênc. rural (Online) ; 53(7): e20220005, 2023. tab, graf
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1404277

RESUMO

ABSTRACT: Genetic variability is the basis for coffee genetic breeding. This study evaluated the potential of leaf anatomy and morpho-agronomic traits in studies of genetic variability in C. canephoracultivars. Ten genotypes were distributed in randomized block designs with three replicates. Significant differences among genotypes were detected by F-test (P < 0.05) for 13 of 15 evaluated traits. These results evidenced the heterogeneity of the studied cultivars, which is essential in composition of genetic basis in breeding programs. The Scott-Knott test detected variability among genotypes, grouped into up to four mean groups. Leaf anatomy traits presented the largest variations. Five out of seven leaf anatomy traits presented heritability higher than 80%, with emphasis on stomatal density (95.69%) and stomatal pore length (92.72%). Positive correlations were observed among morpho-agronomic and anatomic traits. Cluster analysis used the Mahalanobis general distance (D2) as a measure of genetic dissimilarity and divided the genotypes into two distinct groups. The inclusion of leaf anatomic traits to characterize C. canephoragenotypes may assist plant breeders with better genetic discrimination and with greater security in plant selection when composing cultivars.


RESUMO: A variabilidade genética é a base para o progresso genético em café. Este estudo teve como objetivo, avaliar o potencial de caracteres morfoagronômicos e anatômicos foliares em estudos de variabilidade genética entre cultivares de Coffea canephora. Dez genótipos foram distribuídos em um experimento seguindo delineamento em blocos ao acaso com três repetições. Foram detectadas diferenças significativas entre os genótipos pelo teste F (P < 0,05) para 13 dos 15 caracteres avaliados. Esses resultados evidenciaram a heterogeneidade entre as cultivares estudadas, o que é essencial para a composição da base genética e avanço dos programas de melhoramento. O teste de Scott e Knott detectou as diferenças entre os genótipos, separando-os em quatro grupos. Os caracteres anatômicos foliares apresentaram as maiores variações. Cinco, dentre os sete caracteres anatômicos foliares, apresentaram estimativas de herdabilidade superiores a 80% com destaque para a densidade estomática (95,69%) e comprimento do poro estomático (92,72%). Correlações positivas foram observadas entre caracteres morfoagronômicos e anatômicos foliares. A análise de agrupamento, considerando a distância de Mahalanobis como medida de dissimilaridade (D²), apontou a distinção de dois grupos de genótipos. A inclusão de caracteres anatômicos foliares na caracterização de genótipos de C. canephora pode auxiliar os melhoristas de plantas na melhor discriminação entre genótipos e maior segurança na seleção de clones para geração de novas cultivares.

2.
Plants (Basel) ; 10(4)2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33800618

RESUMO

Despite the negative impacts of increased ultraviolet radiation intensity on plants, these organisms continue to grow and produce under the increased environmental UV levels. We hypothesized that ambient UV intensity can generate acclimations in plant growth, leaf morphology, and photochemical functioning in modern genotypes of Coffea arabica and C. canephora. Coffee plants were cultivated for ca. six months in a mini greenhouse under either near ambient (UVam) or reduced (UVre) ultraviolet regimes. At the plant scale, C. canephora was substantially more impacted by UVam when compared to C. arabica, investing more carbon in all juvenile plant components than under UVre. When subjected to UVam, both species showed anatomic adjustments at the leaf scale, such as increases in stomatal density in C. canephora, at the abaxial and adaxial cuticles in both species, and abaxial epidermal thickening in C. arabica, although without apparent impact on the thickness of palisade and spongy parenchyma. Surprisingly, C. arabica showed more efficient energy dissipation mechanism under UVam than C. canephora. UVam promoted elevated protective carotenoid content and a greater use of energy through photochemistry in both species, as reflected in the photochemical quenching increases. This was associated with an altered chlorophyll a/b ratio (significantly only in C. arabica) that likely promoted a greater capability to light energy capture. Therefore, UV levels promoted different modifications between the two Coffea sp. regarding plant biomass production and leaf morphology, including a few photochemical differences between species, suggesting that modifications at plant and leaf scale acted as an acclimation response to actual UV intensity.

3.
An Acad Bras Cienc ; 91(1): e20180312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30994764

RESUMO

This study aims to identify phenolic compounds in dichloromethane and methanolic extracts of the rhizome of Renealmia nicolaioides collected in the North Region of Brazil. Two known diarylheptanoids, 1,7-bis(4-hydroxyphenyl)-(1E)-1-hepten-3-one (1), and 5R-1,7-bis(4-hydroxyphenyl)-1E-hepten-5-ol (2), and a new one (1R,2S,5S)-2-hydroxy-1,7(p-hydroxyphenyl)-centrolobine (3), as well as one flavonoid, 3-metoxi-quercetin (4) were isolated by chromatographic procedure and identified by spectroscopic techniques (1H and13C NMR, HRMS and CD). The acetyl derivative of 2 was used to confirm its structure. All four compounds are reported for the first time for this genus, and this is the first occurrence of compound 1 as a natural metabolite. The results reported here are unprecedented for the genus Renealmia.


Assuntos
Diarileptanoides/química , Fenóis/química , Extratos Vegetais/química , Rizoma/química , Zingiberaceae/química , Brasil , Cromatografia Líquida de Alta Pressão , Diarileptanoides/isolamento & purificação , Estrutura Molecular , Fenóis/isolamento & purificação , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray
4.
Mem Inst Oswaldo Cruz ; 109(6): 767-74, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25317704

RESUMO

Lipid bodies [lipid droplets (LBs)] are lipid-rich organelles involved in lipid metabolism, signalling and inflammation. Recent findings suggest a role for LBs in host response to infection; however, the potential functions of this organelle in Toxoplasma gondii infection and how it alters macrophage microbicidal capacity during infection are not well understood. Here, we investigated the role of host LBs in T. gondii infection in mouse peritoneal macrophages in vitro. Macrophages cultured with mouse serum (MS) had higher numbers of LBs than those cultured in foetal bovine serum and can function as a model to study the role of LBs during intracellular pathogen infection. LBs were found in association with the parasitophorous vacuole, suggesting that T. gondii may benefit from this lipid source. Moreover, increased numbers of macrophage LBs correlated with high prostaglandin E2 (PGE2) production and decreased nitric oxide (NO) synthesis. Accordingly, LB-enriched macrophages cultured with MS were less efficient at controlling T. gondii growth. Treatment of macrophages cultured with MS with indomethacin, an inhibitor of PGE2 production, increased the microbicidal capacity against T. gondii. Collectively, these results suggest that culture with MS caused a decrease in microbicidal activity of macrophages against T. gondii by increasing PGE2 while lowering NO production.


Assuntos
Gotículas Lipídicas/parasitologia , Ativação de Macrófagos/fisiologia , Macrófagos Peritoneais/parasitologia , Toxoplasma/fisiologia , Vacúolos/parasitologia , Animais , Bovinos , Interações Hospedeiro-Parasita , Indometacina/farmacologia , Gotículas Lipídicas/fisiologia , Macrófagos Peritoneais/química , Macrófagos Peritoneais/fisiologia , Macrófagos Peritoneais/ultraestrutura , Masculino , Camundongos , Camundongos Endogâmicos C3H , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óxido Nítrico/biossíntese , Cultura Primária de Células , Prostaglandinas E/antagonistas & inibidores , Prostaglandinas E/biossíntese , Vacúolos/fisiologia
5.
Mem. Inst. Oswaldo Cruz ; 109(6): 767-774, 09/09/2014. tab, graf
Artigo em Inglês | LILACS | ID: lil-724002

RESUMO

Lipid bodies [lipid droplets (LBs)] are lipid-rich organelles involved in lipid metabolism, signalling and inflammation. Recent findings suggest a role for LBs in host response to infection; however, the potential functions of this organelle in Toxoplasma gondii infection and how it alters macrophage microbicidal capacity during infection are not well understood. Here, we investigated the role of host LBs in T. gondii infection in mouse peritoneal macrophages in vitro. Macrophages cultured with mouse serum (MS) had higher numbers of LBs than those cultured in foetal bovine serum and can function as a model to study the role of LBs during intracellular pathogen infection. LBs were found in association with the parasitophorous vacuole, suggesting that T. gondii may benefit from this lipid source. Moreover, increased numbers of macrophage LBs correlated with high prostaglandin E2 (PGE2) production and decreased nitric oxide (NO) synthesis. Accordingly, LB-enriched macrophages cultured with MS were less efficient at controlling T. gondii growth. Treatment of macrophages cultured with MS with indomethacin, an inhibitor of PGE2 production, increased the microbicidal capacity against T. gondii. Collectively, these results suggest that culture with MS caused a decrease in microbicidal activity of macrophages against T. gondii by increasing PGE2 while lowering NO production.


Assuntos
Animais , Bovinos , Masculino , Camundongos , Gotículas Lipídicas/parasitologia , Ativação de Macrófagos/fisiologia , Macrófagos Peritoneais/parasitologia , Toxoplasma/fisiologia , Vacúolos/parasitologia , Interações Hospedeiro-Parasita , Indometacina/farmacologia , Gotículas Lipídicas/fisiologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Macrófagos Peritoneais/química , Macrófagos Peritoneais/fisiologia , Macrófagos Peritoneais/ultraestrutura , Óxido Nítrico/biossíntese , Cultura Primária de Células , Prostaglandinas E/antagonistas & inibidores , Prostaglandinas E/biossíntese , Vacúolos/fisiologia
6.
Biocell ; 36(2): 83-90, Aug. 2012. ilus
Artigo em Inglês | LILACS | ID: lil-662145

RESUMO

The success of sexual plant reproduction is directly influenced by specific interactions between the pollen and pistil. Light, fluorescence and scanning electron microscopy techniques were used to evaluate the steps of pollination in sour passion fruit plants (Passiflora edulis Sims). In the compatible interaction, pollen tubes grow through stigma projections towards the ovary. The pollen grain surface was found to be spheroidal and to consist of heteroreticulate exine with six colpi. Furthermore, analysis in vivo of pollen-pistil interactions indicated that stigmas of flowers 24 hours before anthesis are unable to discriminate compatible (genetically unrelated) and incompatible (genetically related) pollen grains. Taken together, these results provide insight into the cellular mechanisms underlying pollination in passion fruit plants.


Assuntos
Flores/metabolismo , Flores/ultraestrutura , Passiflora/química , Pólen/metabolismo , Pólen/ultraestrutura , Polinização/fisiologia , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Passiflora/fisiologia
7.
Biocell ; 36(2): 83-90, Aug. 2012. ilus
Artigo em Inglês | BINACIS | ID: bin-129058

RESUMO

The success of sexual plant reproduction is directly influenced by specific interactions between the pollen and pistil. Light, fluorescence and scanning electron microscopy techniques were used to evaluate the steps of pollination in sour passion fruit plants (Passiflora edulis Sims). In the compatible interaction, pollen tubes grow through stigma projections towards the ovary. The pollen grain surface was found to be spheroidal and to consist of heteroreticulate exine with six colpi. Furthermore, analysis in vivo of pollen-pistil interactions indicated that stigmas of flowers 24 hours before anthesis are unable to discriminate compatible (genetically unrelated) and incompatible (genetically related) pollen grains. Taken together, these results provide insight into the cellular mechanisms underlying pollination in passion fruit plants.(AU)


Assuntos
Flores/metabolismo , Flores/ultraestrutura , Passiflora/química , Pólen/metabolismo , Pólen/ultraestrutura , Polinização/fisiologia , Microscopia Eletrônica de Varredura , Microscopia de Polarização , Passiflora/fisiologia
8.
Braz. arch. biol. technol ; 54(5): 1059-1068, Sept.-Oct. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-604268

RESUMO

In this work, the structural and ecophysiological alterations (chlorophyll a fluorescence and photosynthetic pigments), and quantification of Cr, Pb and Zn in the leaf limb, petiole and younger and older roots of water hyacinth from the lower, medium and upper Paraíba do Sul river (PSR) and Imbé river were evaluated. The plants from the medium and upper PSR (more industrialized and populated regions) exhibited lower turgid cell in the root cortex, less root hairs and leaf epidermis, chloroplasts with plastoglobules and increased stroma volume. Higher concentrations of metals were observed in the younger and older roots from the medium PSR plants. The results suggested that the plants from more anthropized regions were able to maintain the maximum quantum yield (Fv/Fm) which was a result from the metabolic fitting, increasing the non-photochemical quenching, reducing total chlorophyll/carotenoids and leading to the structural modifications.

9.
Braz. arch. biol. technol ; 49(6): 881-888, Nov. 2006. ilus, graf
Artigo em Inglês | LILACS | ID: lil-443137

RESUMO

In this study, beta-1,3-glucanase was isolated from Simira glaziovii secretion. The purification process was achieved by a combination of chromatographic methods and was analyzed by SDS-PAGE. The purified enzyme presented an estimated molecular mass of 35 kDa. The optimum pH of enzyme was 5.2


Uma beta-1,3-glucanase foi purificada a partir da secreção de Simira glaziovii, através de vários processos cromatográficos, tendo a análise do perfil protéico acompanhado de SDS-PAGE. A enzima purificada apresentou uma massa molecular estimada de 35 kDa. O pH ótimo obtido para a enzima foi de 5,2.

10.
Biocell ; 24(2): 123-132, Aug. 2000.
Artigo em Inglês | LILACS | ID: lil-335905

RESUMO

Specimens of Chamaesyce thymifolia (Euphorbiaceae) infected and uninfected by Phytomonas sp., a parasite of the Trypanosomatidae family, were anatomically and ultrastructurally analyzed with special emphasis on the laticifer system. C. thymifolia presents branched non-articulated laticifers and was heavily infected by Phytomonas sp. in all collection sites. Infection was often observed in the initial stages inside the vacuole, when the latex particles could be seen. In intermediary stages of laticifer differentiation, Phytomonas sp. were found free in the cytoplasm, inside small vacuoles or in the central vacuole. In differentiated laticifers that had only the plasma membrane, Phytomonas sp. were free in the latex and close to the cell membrane. Infected and uninfected plants showed identical anatomy and ultrastructure and the starch grain numbers in the latex were not reduced in the presence of this flagellate. Biochemical analysis of the latex of infected and uninfected plants presented similar levels of protein, carbohydrate and beta-1,3-glucanase, suggesting that this species is not pathogenic for the host. Besides, all infected plants complete its life cycle. Plants infected with Phytomonas presented occasionally virus like particles and bacteria inside the laticifer tubes.


Assuntos
Animais , Organelas , Plantas , Interações Hospedeiro-Parasita/fisiologia , Trypanosomatina , Organelas , Folhas de Planta , Caules de Planta , Plantas , Raízes de Plantas/metabolismo , Raízes de Plantas/parasitologia , Raízes de Plantas/ultraestrutura
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