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1.
Z Naturforsch C J Biosci ; 76(3-4): 93-102, 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32960783

RESUMO

Hoja santa (Piper auritum) refers to an important presence in Mexican cuisine. The information of this review article was gathered from several electronic sources such as Scopus, Medline, Scielo, ScienceDirect, SciFinder, Web of Science, Google Scholar and Lilacs. Phytochemical studies have revealed the presence of benzoic acid derivatives, phenylpropanoids and triterpenoids, while the essential oils have shown its richness in safrole, hence it has several activities, such as antioxidant, toxicity, insecticidal, anti-diabetic and cytotoxic properties. This review is expected to draw the attention of medical professionals and the general public towards P. auritum as well as to open the door for detailed research in the future.


Assuntos
Compostos Fitoquímicos/química , Piper/crescimento & desenvolvimento , Extratos Vegetais/uso terapêutico , Antioxidantes/química , Antioxidantes/uso terapêutico , Ácido Benzoico/química , Medicina Tradicional , Compostos Fitoquímicos/uso terapêutico , Fitoterapia , Piper/química , Piper/genética , Extratos Vegetais/química
2.
Ann Bot ; 121(5): 1079-1088, 2018 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-29509841

RESUMO

Background and Aims: Global agriculture is facing the challenge of a phenotyping bottleneck due to large-scale screening/breeding experiments with improved breeds. Phenotypic analysis with high-throughput, high-accuracy and low-cost technologies has therefore become urgent. Recent advances in image-based 3D reconstruction offer the opportunity of high-throughput phenotyping. The main aim of this study was to quantify and evaluate the canopy structure of plant populations in two and three dimensions based on the multi-view stereo (MVS) approach, and to monitor plant growth and development from seedling stage to fruiting stage. Methods: Multi-view images of flat-leaf cucumber, small-leaf pepper and curly-leaf eggplant were obtained by moving a camera around the plant canopy. Three-dimensional point clouds were reconstructed from images based on the MVS approach and were then converted into surfaces with triangular facets. Phenotypic parameters, including leaf length, leaf width, leaf area, plant height and maximum canopy width, were calculated from reconstructed surfaces. Accurate evaluation in 2D and 3D for individual leaves was performed by comparing reconstructed phenotypic parameters with referenced values and by calculating the Hausdorff distance, i.e. the mean distance between two surfaces. Key Results: Our analysis demonstrates that there were good agreements in leaf parameters between referenced and estimated values. A high level of overlap was also found between surfaces of image-based reconstructions and laser scanning. Accuracy of 3D reconstruction of curly-leaf plants was relatively lower than that of flat-leaf plants. Plant height of three plants and maximum canopy width of cucumber and pepper showed an increasing trend during the 70 d after transplanting. Maximum canopy width of eggplants reached its peak at the 40th day after transplanting. The larger leaf phenotypic parameters of cucumber were mostly found at the middle-upper leaf position. Conclusions: High-accuracy 3D evaluation of reconstruction quality indicated that dynamic capture of the 3D canopy based on the MVS approach can be potentially used in 3D phenotyping for applications in breeding and field management.


Assuntos
Cucumis sativus/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Piper/anatomia & histologia , Solanum melongena/anatomia & histologia , Agricultura , Cucumis sativus/crescimento & desenvolvimento , Frutas/anatomia & histologia , Frutas/crescimento & desenvolvimento , Fenótipo , Piper/crescimento & desenvolvimento , Melhoramento Vegetal , Folhas de Planta/anatomia & histologia , Folhas de Planta/crescimento & desenvolvimento , Plântula/anatomia & histologia , Plântula/crescimento & desenvolvimento , Solanum melongena/crescimento & desenvolvimento
3.
An. acad. bras. ciênc ; 89(2): 1167-1174, Apr.-June 2017. graf
Artigo em Inglês | LILACS | ID: biblio-886713

RESUMO

ABSTRACT Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN) and blue (BN) both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade). The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.


Assuntos
Fotossíntese/fisiologia , Luz Solar , Óleos Voláteis/metabolismo , Piper/crescimento & desenvolvimento , Piper/efeitos da radiação , Piper/metabolismo , Fotossíntese/efeitos da radiação , Fatores de Tempo , Clorofila/análise , Clorofila/metabolismo , Reprodutibilidade dos Testes , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/efeitos da radiação , Folhas de Planta/metabolismo
4.
An Acad Bras Cienc ; 89(2): 1167-1174, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28489190

RESUMO

Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN) and blue (BN) both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade). The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.


Assuntos
Óleos Voláteis/metabolismo , Fotossíntese/fisiologia , Piper/crescimento & desenvolvimento , Piper/metabolismo , Piper/efeitos da radiação , Luz Solar , Clorofila/análise , Clorofila/metabolismo , Fotossíntese/efeitos da radiação , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Reprodutibilidade dos Testes , Fatores de Tempo
5.
Oecologia ; 177(2): 453-66, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25262120

RESUMO

Plants often recruit frugivorous animals to transport their seeds; however, gut passage can have varying effects on plant fitness depending on the physical and chemical treatment of the seed, the distance seeds are transported, and the specific site of deposition. One way in which plants can mediate the effects of gut passage on fitness is by producing fruit secondary compounds that influence gut-retention time (GRT). Using frugivorous bats (Carollia perspicillata: Phyllostomidae) and Neotropical plants in the genus Piper, we compared GRT of seeds among five plant species (Piper colonense, Piper peltatum, Piper reticulatum, Piper sancti-felicis, and Piper silvivagum) and investigated the role of fruit amides (piperine, piplartine and whole fruit amide extracts from P. reticulatum) in mediating GRT. Our results showed interspecific differences in GRT; P. reticulatum seeds passed most slowly, while P. silvivagum and P. colonense seeds passed most rapidly. Piplartine and P. reticulatum amide extracts decreased GRT, while piperine had no effect. In addition, we examined the effects of GRT on seed germination success and speed in laboratory conditions. For germination success, the effects were species specific; germination success increased with GRT for P. peltatum but not for other species. GRT did not influence germination speed in any of the species examined. Plant secondary compounds have primarily been studied in the context of their defensive role against herbivores and pathogens, but may also play a key role in mediating seed dispersal interactions.


Assuntos
Quirópteros/metabolismo , Trânsito Gastrointestinal , Piper/química , Dispersão de Sementes , Sementes/metabolismo , Animais , Quirópteros/fisiologia , Frutas/química , Frutas/metabolismo , Germinação , Herbivoria , Piper/crescimento & desenvolvimento , Piper/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento
6.
J Insect Sci ; 14: 39, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25373186

RESUMO

Shelter-building behavior by caterpillars provides a mechanism of defense against predators, microenvironment enhancement, and in some cases nutritional benefits. This study provides a detailed description of the life cycle and shelter-building process of caterpillars, and identifies constraints and factors influencing this adaptive behavior in Lepidomys n. sp. near proclea Druce (Pyralidae: Chrysauginae), a tropical dry forest pyralid. Five macroscopic larval instars were detected during the life cycle, and activities performed during shelter-building were categorized and timed. Caterpillar predators were identified, and 20% of all collected larvae died due to attack by parasitoid wasps. Shelter-building behavior was found to be constrained by the ontogenetic stage of caterpillars and influenced by leaf size of the host plant, Piper stipulaceum Opiz (Piperales: Piperaceae) . A similar pattern of shelter-building behavior exhibited by Tosale n. sp. near cuprealis larvae that coexisted in the same host plant is also described. Larvae of the second species were significantly less abundant than those of Lepidomys and hatched one month later in the rainy season, which could indicate some competitive interactions between these two pyralid species.


Assuntos
Cadeia Alimentar , Mariposas/fisiologia , Mariposas/parasitologia , Piper/crescimento & desenvolvimento , Animais , Comportamento Animal , Mecanismos de Defesa , Larva/parasitologia , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento , Especificidade da Espécie
7.
Phytochemistry ; 106: 86-93, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25041698

RESUMO

HPLC-DAD and principal component analysis (PCA) of the (1)H NMR spectrum of crude plant extracts showed high chemical variability among seedlings and adult organs of Piper gaudichaudianum. While gaudichaudianic acid was the major compound in the adult leaves, apiole and dillapiole were the major compounds in their seedling leaves. By the 15th month of seedling growth, the levels of apiole and dillapiole decreased and gaudichaudianic acid appeared along with two compounds, biosynthetically related to gaudichaudianic acid.


Assuntos
Benzoatos/química , Piper/química , Compostos Alílicos , Cromatografia Líquida de Alta Pressão , Dioxóis/química , Estrutura Molecular , Piper/crescimento & desenvolvimento , Extratos Vegetais/química , Folhas de Planta/química , Análise de Componente Principal
8.
PLoS One ; 9(12): e115052, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25551554

RESUMO

BACKGROUND: Intercropping systems could increase crop diversity and avoid vulnerability to biotic stresses. Most studies have shown that intercropping can provide relief to crops against wind-dispersed pathogens. However, there was limited data on how the practice of intercropping help crops against soil-borne Phytophthora disease. PRINCIPAL FINDINGS: Compared to pepper monoculture, a large scale intercropping study of maize grown between pepper rows reduced disease levels of the soil-borne pepper Phytophthora blight. These reduced disease levels of Phytophthora in the intercropping system were correlated with the ability of maize plants to form a "root wall" that restricted the movement of Phytophthora capsici across rows. Experimentally, it was found that maize roots attracted the zoospores of P. capsici and then inhibited their growth. When maize plants were grown in close proximity to each other, the roots produced and secreted larger quantities of 2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one (DIMBOA) and 6-methoxy-2-benzoxazolinone (MBOA). Furthermore, MBOA, benzothiazole (BZO), and 2-(methylthio)-benzothiazole (MBZO) were identified in root exudates of maize and showed antimicrobial activity against P. capsici. CONCLUSIONS: Maize could form a "root wall" to restrict the spread of P. capsici across rows in maize and pepper intercropping systems. Antimicrobe compounds secreted by maize root were one of the factors that resulted in the inhibition of P. capsici. These results provide new insights into plant-plant-microbe mechanisms involved in intercropping systems.


Assuntos
Agricultura/métodos , Interações Hospedeiro-Parasita , Piper/crescimento & desenvolvimento , Piper/parasitologia , Doenças das Plantas/prevenção & controle , Doenças das Plantas/parasitologia , Solo/parasitologia , Zea mays/crescimento & desenvolvimento , Ambiente Controlado , Phytophthora/efeitos dos fármacos , Phytophthora/fisiologia , Piper/microbiologia , Doenças das Plantas/microbiologia , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Raízes de Plantas/microbiologia , Raízes de Plantas/parasitologia , Rizosfera , Microbiologia do Solo , Zea mays/química
9.
Pharm Biol ; 50(8): 1045-52, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22486533

RESUMO

CONTEXT: Piper sarmentosum Roxb. (Piperaceae) is a traditional medicinal as well as a culinary plant in South East Asian countries, whereby aerial parts of the plant are consumed as a vegetable in various forms and the whole plant or parts are used as folk remedies, alone or in combination with other herbs, to treat various ailments. The plant has extensively been investigated in a broad range of studies to provide scientific evidence for folklore claims or to find new therapeutic uses; however, heretofore, a summary of the data are not available. OBJECTIVE: In order to describe nutritional and therapeutic potential of P. sarmentosum and summarize scientific evidence that supports traditional claims, a literature review and latest advances in research of the plant are given herein. MATERIALS AND METHODS: The literature has been retrieved from a number of databases such as Google Scholar, PubMed, Medline, Science Direct and SciFinder. The articles related to synthetic work, ecology and agriculture have been excluded. RESULTS AND DISCUSSION: The review has not only revealed a number of pharmacological activities supporting the traditional claims but indicates new prospects for the plant. Antiangiogenic activity and toxicity studies suggest the usage of the plant in treating diseases involving neo-vascularization. The available efficacy, safety, pharmacokinetic and stability data urge clinical studies on extracts of the plant. CONCLUSION: The present review may be helpful to future researchers intending to investigate the plant and natural pharmaceutical industry for preparing evidence-based formulations.


Assuntos
Piper/química , Extratos Vegetais/uso terapêutico , Inibidores da Angiogênese/efeitos adversos , Inibidores da Angiogênese/farmacologia , Inibidores da Angiogênese/uso terapêutico , Animais , Anti-Infecciosos/efeitos adversos , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Antioxidantes/efeitos adversos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Sudeste Asiático , Etnofarmacologia , Alimento Funcional/efeitos adversos , Alimento Funcional/análise , Humanos , Medicina Tradicional do Leste Asiático , Valor Nutritivo , Piper/efeitos adversos , Piper/crescimento & desenvolvimento , Extratos Vegetais/efeitos adversos , Extratos Vegetais/farmacologia
10.
Braz. j. microbiol ; 42(3): 1001-1006, July-Sept. 2011. tab
Artigo em Inglês | LILACS | ID: lil-607530

RESUMO

In vitro activity of the essential oil from Piper diospyrifolium leaves was tested using disk diffusion techniques. The antifungal assay showed significant potencial antifungal activity: the oil was effective against several clinical fungal strains. The majority compounds in the essential oil were identified as sesquiterpenoids by GC-MS and GC-FID techniques.


Assuntos
Antifúngicos , Técnicas In Vitro , Estruturas Vegetais , Piper/crescimento & desenvolvimento , Piper/genética , Piperaceae/genética , Sesquiterpenos/análise , Árvores , Oceano Atlântico , Métodos , Óleos Voláteis , Folhas de Planta , Preparações de Plantas , Métodos
11.
Oecologia ; 165(2): 357-68, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20677015

RESUMO

Understanding the effects of disturbance and secondary succession on spatio-temporal patterns in the abundance of species is stymied by a lack of long-term demographic data, especially in response to infrequent and high intensity disturbances, such as hurricanes. Moreover, resistance and resilience to hurricane-induced disturbance may be mediated by legacies of previous land use, although such interactive effects are poorly understood, especially in tropical environments. We address these central issues in disturbance ecology by analyzing an extensive dataset, spanning the impacts of Hurricanes Hugo and Georges, on the abundance of a Neotropical walking stick, Lamponius portoricensis, in tabonuco rainforest of Puerto Rico during the wet and dry seasons from 1991 to 2007. By synthesizing data from two proximate sites in tabonuco forest, we show that resistance to Hurricane Hugo (97% reduction in abundance) was much less than resistance to Hurricane Georges (21% reduction in abundance). Based on a powerful statistical approach (generalized linear mixed-effects models with Poisson error terms), we documented that the temporal trajectories of abundance during secondary succession (i.e., patterns of resilience) differed between hurricanes and among historical land use categories, but that the effects of hurricanes and land use histories were independent of each other. These complex results likely arise because of differences in the intensities of the two hurricanes with respect to microclimatic effects (temperature and moisture) in the forest understory, as well as to time-lags in the response of L. portoricensis to changes in the abundance and distribution of preferred food plants (Piper) in post-hurricane environments.


Assuntos
Tempestades Ciclônicas , Ecossistema , Insetos/fisiologia , Árvores/fisiologia , Animais , Umidade , Piper/crescimento & desenvolvimento , Piper/fisiologia , Porto Rico , Chuva , Especificidade da Espécie , Temperatura , Fatores de Tempo , Árvores/crescimento & desenvolvimento
12.
Rev. bras. plantas med ; 13(spe): 559-563, 2011. graf, tab
Artigo em Português | LILACS | ID: lil-618331

RESUMO

O estabelecimento de espécies usadas como porta-enxerto, importantes na olericultura, podem ser multiplicadas por meio da estaquia com auxílio de fitorreguladores. Objetivou-se com este trabalho avaliar a influência do AIB no estabelecimento de espécies nativas do gênero Piper com potencial de uso como porta-enxerto de Piper nigrum. Estacas de P. Arboreum, P. amplum e P. sp foram submetidas a diferentes dosagens de AIB (0, 2000, 4000, 6000 e 8000 mg.L-1) e mantidas em estufa agrícola com irrigação intermitente com temperatura e umidade controlados. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 3x5 (3 espécies de Piper x 5 dosagens de AIB) e composto por 3 repetições por tratamento, sendo cada parcela composta por 10 estacas. A avaliação foi realizada aos 45 dias de transplantio e as variáveis analisadas foram: índice de sobrevivência, número médio de folhas, número médio de brotos e comprimento médio do maior broto. A espécie Piper arboreum apresentou bons resultados referentes ao crescimento da parte aérea independentemente da concentração de AIB empregada.


The establishment of species used as rootstock, which are important in horticulture crop scan may be multiplied, with the aid of growth regulators, by cutting. The objective of this study was to evaluate the influence of IBA on the establishment of native species of the genus Piper with potential use as rootstock of Piper nigrum. Cuttings of P. arboreum, P. amplum and P. sp were treated with different concentrations of IBA (0 ,2000, 4000, 6000 and 8000mg.L-1) and maintained in a greenhouse with intermittent irrigation, with the temperature and humidity controlled. The experimental design was completely randomized in a factorial 3x5 plan (3 Piper species x5 doses of IBA) and comprising of three repetitions per treatment, each plot consisting of 10 cuttings. The evaluation was performed at 45 days of transplanting and the analyzed variables were: survival rate, the number of leaves, the number of shoots and the length of the largest shoot. The Piper arboretum species showed the best growth results for the aerial part independent of the IBA concentration used.


Assuntos
Piperaceae/crescimento & desenvolvimento , Piper nigrum/crescimento & desenvolvimento , Piper/crescimento & desenvolvimento , Fusariose/prevenção & controle
13.
Planta Med ; 76(13): 1473-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20195961

RESUMO

Piper peltatum L. is used for the treatment of inflammation, malaria, and other ailments. 4-Nerolidylcatechol (4-NC) is a valuable natural product that has important anti-inflammatory, antimalarial, and antioxidant properties. 4-NC is a component of P. peltatum and P. umbellatum extracts, which are used in cosmetics. The aim of this work was to evaluate the production of plant biomass and the production of 4-NC in roots of cultivated P. peltatum over a full life cycle. Seedlings were produced in a greenhouse and then transplanted. The weight of dry plant parts (leaves, stems, roots, and inflorescences); numbers of stems, leaves, and inflorescences; and the leaf-to-stem ratio were evaluated at intervals of 60 days after transplanting (DAT). Extracts were prepared using 1:1 ethanol-chloroform and an ultrasound bath. Roots, leaves, and inflorescences contained 4-NC according to TLC photodensitometry analysis. Quantification of 4-NC in root extracts was performed using HPLC-DAD analysis. Per-hectare production of 4-NC by roots was estimated based on quantitative HPLC analysis and biomass data. Optimal per-hectare yields of 4-NC were obtained by harvesting roots between 350 and 400 DAT. In this period, the average yield was 27 kg 4-NC per hectare. Importantly, at the time of maximal overall production of root biomass (470 DAT), there was a decrease in the production of 4-NC (23.8 kg/ha), probably due to the onset of senescence.


Assuntos
Catecóis/metabolismo , Piper/metabolismo , Extratos Vegetais/metabolismo , Biomassa , Catecóis/análise , Piper/química , Piper/crescimento & desenvolvimento , Extratos Vegetais/química , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Estruturas Vegetais , Plantas Medicinais
14.
Oecologia ; 161(1): 43-56, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19412623

RESUMO

In moist tropical forests resprouting may be an important component of life history, contributing to asexual reproduction through the clonal spread of individuals derived from shoot fragments. However, in contrast to other ecosystems where resprouting is common, the ecological correlates of resprouting capacity in tropical forests remain largely unexplored. In this study we characterized shade tolerance, resprouting capacity and sexual reproductive success of eight co-occurring Piper species from lowland forests of Panama. In field experiments we found that shade-tolerant Piper species had a higher capacity to regenerate from excised or pinned stem fragments than light-demanding species in both gap and understory light conditions. In contrast, shade-tolerant species had lower recruitment probabilities from seeds, as a consequence of lower initial seed viability, and lower seedling emergence rates. All Piper species needed gap conditions for successful seedling establishment. Of 8,000 seeds sown in the understory only 0.2% emerged. In gaps, seed germination of light-demanding species was between 10 and 50%, whereas for shade-tolerant species it was 0.5-9.8%. We propose that the capacity to reproduce asexually from resprouts could be adaptive for shade-tolerant species that are constantly exposed to damage from falling litter in the understory. Resprouting may allow Piper populations to persist and spread despite the high rate of pre-dispersal seed predation and low seed emergence rates. Across Piper species, we detected a trade-off between resprouting capacity and the annual viable seed production per plant but not with annual seed mass produced per plant. This suggests that species differences in sexual reproductive success may not necessarily result from differential resource allocation. Instead we suggest that low sexual reproductive success in the understory may in part reflect reduced genetic diversity in populations undergoing clonal growth, resulting in self-fertilization and in-breeding depression.


Assuntos
Adaptação Fisiológica/fisiologia , Luz , Piper/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Reprodução Assexuada/fisiologia , Análise de Variância , Carbono/metabolismo , Genética Populacional , Germinação/fisiologia , Nitrogênio/metabolismo , Panamá , Folhas de Planta/metabolismo , Plântula/crescimento & desenvolvimento , Especificidade da Espécie , Clima Tropical
15.
Can J Microbiol ; 53(1): 63-74, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17496951

RESUMO

Bacterial contamination is a serious problem that causes severe loss of in vitro grown cultures of a number of plants. This problem becomes even more acute if the bacterial contamination is of endophytic origin. In such cases, identification and characterization of the contaminants is essential for achieving specific control of the contaminants through selective use of antibiotic agents, especially if the routinely used contamination control methods practiced elsewhere in tissue culture studies are ineffective. Such is the case with the bacterial contamination observed in the present study. The five endophytic bacteria associated with Piper nigrum and Piper colubrinum, four endophytic bacteria associated with Taxus baccata subsp. wallichiana, two endophytic bacteria associated with Withania somnifera, and two bacteria common to all these plant species were isolated and characterized based on morphological and biochemical tests. Their taxonomic positions based on similarity indices were determined. A control strategy against these bacteria has been developed based on bacteriostatic or bactericidal actions of 12 antibiotics at three different concentrations by solid and liquid antibiogramme assays.


Assuntos
Piper/microbiologia , Doenças das Plantas/microbiologia , Taxus/microbiologia , Withania/microbiologia , Antibacterianos/farmacologia , Bactérias Aeróbias/classificação , Bactérias Aeróbias/efeitos dos fármacos , Bactérias Anaeróbias/classificação , Bactérias Anaeróbias/efeitos dos fármacos , Meios de Cultura , Técnicas In Vitro , Piper/crescimento & desenvolvimento , Esterilização/métodos , Taxus/crescimento & desenvolvimento , Withania/crescimento & desenvolvimento
16.
Bioresour Technol ; 95(2): 215-21, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15246447

RESUMO

Some organic materials have shown a suppressive effect on several diseases induced by soilborne plant pathogens. We have carried out a laboratory experiment (microcosm) to ascertain the influence of the stabilisation process of sewage sludge on it biopesticide effect when Pythium ultimum or Phytophthora sp. were introduced to soil as pathogens for pea or pepper. When P. ultimum was introduced there was a 63.8% reduction in the weight of the stems grown in the control, 47.6% in the presence of sewage sludge, but only 24.7% with compost. The same biopesticide effect was evident from the weight of the roots. The biopesticide effect was also strong when compost was used as organic amendment in the presence of Phytophthora, as could be seen from stem and shoot weight and length. The data showed that the degree of stabilisation of the organic material (compost) had a positive influence on it biopesticide effect. The changes undergone by a soil after the addition of organic materials helped to explain the biopesticide effect of the amendment. The organic treatments reduced P. ultimum and Phytophthora sp. populations.


Assuntos
Oomicetos/efeitos dos fármacos , Praguicidas/toxicidade , Piper/crescimento & desenvolvimento , Esgotos , Solo , Análise de Variância , Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Fungos/crescimento & desenvolvimento , Piper/microbiologia , Raízes de Plantas/crescimento & desenvolvimento
17.
J Chem Ecol ; 29(11): 2499-514, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14682530

RESUMO

The tropical rainforest shrub Piper cenocladum, which is normally defended against herbivores by a mutualistic ant, contains three amides that have various defensive functions. While the ants are effective primarily against specialist herbivores, we hypothesized that these secondary compounds would be effective against a wider range of insects, thus providing a broad array of defenses against herbivores. We also tested whether a mixture of amides would be more effective against herbivores than individual amides. Diets spiked with amides were offered to five herbivores: a naïve generalist caterpillar (Spodoptera frugiperda), two caterpillar species that are monophagous on P. cenocladum (Eois spp.), leaf-cutting ants (Atta cephalotes), and an omnivorous ant (Paraponera clavata). Amides had negative effects on all insects, whether they were naïve, experienced, generalized, or specialized feeders. For Spodoptera, amide mixtures caused decreased pupal weights and survivorship and increased development times. Eois pupal weights, larval mass gain, and development times were affected by additions of individual amides, but increased parasitism and lower survivorship were caused only by the amide mixture. Amide mixtures also deterred feeding by the two ant species, and crude plant extracts were strongly deterrent to P. clavata. The mixture of all three amides had the most dramatic deterrent and toxic effects across experiments, with the effects usually surpassing expected additive responses, indicating that these compounds can act synergistically against a wide array of herbivores.


Assuntos
Amidas/isolamento & purificação , Amidas/farmacologia , Piper/química , Piper/crescimento & desenvolvimento , Plantas Comestíveis , Animais , Formigas , Comportamento Alimentar , Larva , Mariposas , Dinâmica Populacional
18.
Phytochem Anal ; 14(5): 281-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14515999

RESUMO

A rapid, sensitive and reliable reverse-phase HPLC method was used for the quantitative determination of the anti-fungal and insecticide amides, dihydropiplartine (1), piplartine (2), deltaalpha,beta-dihydropiperine (3) and pellitorine (4) in plants in natura, in plantlets in vitro and ex vitro, and in callus of Piper tuberculatum. Well-resolved peaks were obtained with good detection response and linearity in the range of 15.0-3000 microg/mL. The plants in natura contained compounds 1-4, the plantlets ex vitro and in vitro accumulated compounds 1-2 and 1-4, respectively, while only amide 4 was found in callus.


Assuntos
Amidas/análise , Antifúngicos/análise , Inseticidas/análise , Piper/química , Piperidinas/análise , Piperidonas/análise , Cromatografia Líquida de Alta Pressão/métodos , Técnicas de Cultura , Ácidos Graxos Insaturados/análise , Estrutura Molecular , Piper/crescimento & desenvolvimento , Extratos Vegetais/química , Alcamidas Poli-Insaturadas , Análise Espectral
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