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1.
Zhongguo Zhong Yao Za Zhi ; 40(10): 2047-9, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26390671

RESUMO

Qumazi is a commonly used Tibetan medicine. With a long history, it can be found in the Four Medical Tantras written by gYu-thog rNying-ma Yon-tan mGon-po since the 8th century AD. Qumazi grows in mudflats and fields, including species growing in highlands, lowlands, mountains and farmlands. According to records in Crystal Beads Materia Medica, it features green sword-shaped leaves, thin stems with red veins, inserted panicles, white chicken-like flowers and copper needle row-like roots. However, there are many inconsistent morphological descriptions for Qumazi plants in many Chinese versions of Tibetan medicine books. In this article, after studying ancient and modern Tibetan medicine books, consulting experts and conducting surveys, the authors confirmed that Qumazi belongs to Rheum of Polygonaceae, including Rheum nobile Hook. f. et. Thoms, R. globulosum Gage, R. alexandrae Hook. f. et. Thoms, R. pumilum Maxim and R. delavayi Franch. In some regions, Qumazi is substituted by R. spiciforme Royle and R. przewalskyi Losinsk. After the Chinese version of Qinghai-Tibet Plateau Drug Illustrations was published in 1972, Qumazi has been miswritten as P. sibiricum Laxm in many Chinese versions of Tibetan medicine books, perhaps because P. sibiricum Laxm has many similar features with Qumazi as described in Crystal Beads Materia Medica and then is mistranslated from Tibetan to Chinese versions. According to records, Qumazi can reduce edema and is mainly applied to treat the minamata disease in clinic.


Assuntos
Medicina Tradicional Tibetana/história , Polygonaceae/química , China , História Antiga , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Polygonaceae/anatomia & histologia , Polygonaceae/crescimento & desenvolvimento , Obras Médicas de Referência
2.
Tsitol Genet ; 48(1): 52-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24791473

RESUMO

In the present paper, detailed cytomorphological investigations in Oxyria digyna Hill. from Kashmir Himalaya-India have been reported for the first time. All the of 14 investigated populations of O. digyna are diploid based on x = 7. Out of these in two populations 0-2B chromosomes have been recorded for the first time while 6 populations differed significantly in their meiotic characteristics. Meiotic abnormalities during male meiosis observed include inter PMC chromatin transfer (cytomixis). Non-synchronous disjunction of some bivalents, laggards and bridges at anaphases and telophases. Consequent to these meiotic anomalies, microsporogenesis in meiocytes is abnormal resulting in to dyads, triads and polyads with or without micronuclei. The overall effect is seen in reduced pollen fertility. Unreduced pollen grains were observed in some populations, which differed significantly in their size compared to the normal (reduced) pollen grains. It is observed that a smaller frequency of pollen grains differed morphologically in Aharbal and Yosmarg populations. The remaining eight populations showed regular meiotic course, normal microsporogenesis and high percentage of pollen fertility (95.09-99.09%).


Assuntos
Aberrações Cromossômicas , Cromossomos de Plantas , Pólen/ultraestrutura , Polygonaceae/ultraestrutura , Altitude , Cromossomos de Plantas/genética , Cromossomos de Plantas/ultraestrutura , Fertilidade , Índia , Meiose/genética , Meiose/fisiologia , Infertilidade das Plantas , Pólen/genética , Polygonaceae/genética , Polygonaceae/crescimento & desenvolvimento
3.
Zhongguo Zhong Yao Za Zhi ; 38(22): 3857-60, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24558864

RESUMO

To achieve sustainable resources use of Polygonum multiflorum, adventitious roots were efficiently induced and cultured by suspension culture. In order to obtain optimal medium for induction adventitious roots from the young stems of P. multiflorum, MS medium was optimized by supplementing with different concentrations of sucrose and plant growth substances. The optimal medium for suspension culture of adventitious roots was determined by orthogonal design. The adventitious roots with suspension culture were subcultured, and the growth curve was also determined. Furthermore, the effective compound in adventitious roots was detected. The result indicated that the optimal medium for efficient induction of adventitious roots was MS medium containing 4% w/v sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) 6-BA. The optimal medium for suspension culture of adventitious roots was MS medium containing 3% sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) ABT-7.2,3,5,4'-tetrahydroxyl-diphenyl-ethylene-2-O-beta-D-glucoside was detected in adventitious roots, which was effective compound in medicinal material of P. multiflorum. In conclusion, the experiment achieved efficient induction and suspension culture of adventitious roots of P. multiflorum, and laid a foundation for the research on the sustainable use of traditional Chinese medicine resources.


Assuntos
Raízes de Plantas/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/métodos , Meios de Cultura/química , Meios de Cultura/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo , Polygonaceae/metabolismo , Sacarose/metabolismo
4.
Zhongguo Zhong Yao Za Zhi ; 38(22): 3988-90, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24558889

RESUMO

Recently the safety of Heshouwu become a focus, but the reasons of its hepotoxicity are confused. On the basis of literature research, some findings on species and usage custom maybe supply some clues to explain the reasons of its hepotoxicity. Heshouwu had red Heshouwu (male) and white Heshouwu (female) in ancient literature, and traditional usage was use of the male and female together. The Latin name of red Heshouwu is Fallopia multiflora, and that of the white one is F. multiflora var. multiflora.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Polygonaceae/química , China , Células Germinativas Vegetais/crescimento & desenvolvimento , História do Século XV , História Antiga , História Medieval , Humanos , Polygonaceae/anatomia & histologia , Polygonaceae/classificação , Polygonaceae/crescimento & desenvolvimento , Obras Médicas de Referência
5.
PLoS One ; 17(1): e0261742, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34995300

RESUMO

Extreme weather and globalisation leave our climate vulnerable to invasion by alien species, which have negative impacts on the economy, biodiversity, and ecosystem services. Rapid and accurate identification is key to the control of invasive alien species. However, visually similar species hinder conservation efforts, for example hybrids within the Japanese Knotweed complex.We applied the novel method of ATR-FTIR spectroscopy combined with chemometrics (mathematics applied to chemical data) to historic herbarium samples, taking 1580 spectra in total. Samples included five species from within the interbreeding Japanese Knotweed complex (including three varieties of Japanese Knotweed), six hybrids and five species from the wider Polygonaceae family. Spectral data from herbarium specimens were analysed with several chemometric techniques: support vector machines (SVM) for differentiation between plant types, supported by ploidy levels; principal component analysis loadings and spectral biomarkers to explore differences between the highly invasive Reynoutria japonica var. japonica and its non-invasive counterpart Reynoutria japonica var. compacta; hierarchical cluster analysis (HCA) to investigate the relationship between plants within the Polygonaceae family, of the Fallopia, Reynoutria, Rumex and Fagopyrum genera.ATR-FTIR spectroscopy coupled with SVM successfully differentiated between plant type, leaf surface and geographical location, even in herbarium samples of varying age. Differences between Reynoutria japonica var. japonica and Reynoutria japonica var. compacta included the presence of two polysaccharides, glucomannan and xyloglucan, at higher concentrations in Reynoutria japonica var. japonica than Reynoutria japonica var. compacta. HCA analysis indicated that potential genetic linkages are sometimes masked by environmental factors; an effect that can either be reduced or encouraged by altering the input parameters. Entering the absorbance values for key wavenumbers, previously highlighted by principal component analysis loadings, favours linkages in the resultant HCA dendrogram corresponding to expected genetic relationships, whilst environmental associations are encouraged using the spectral fingerprint region.The ability to distinguish between closely related interbreeding species and hybrids, based on their spectral signature, raises the possibility of using this approach for determining the origin of Japanese knotweed infestations in legal cases where the clonal nature of plants currently makes this difficult and for the targeted control of species and hybrids. These techniques also provide a new method for supporting biogeographical studies.


Assuntos
Espécies Introduzidas , Ploidias , Polygonaceae/classificação , Polygonaceae/crescimento & desenvolvimento , Polygonaceae/genética , Espectroscopia de Infravermelho com Transformada de Fourier
6.
Pest Manag Sci ; 63(2): 134-40, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17171722

RESUMO

The inclusion of 52 potential non-crop or wild species in new OECD guidelines for terrestrial non-target plant (TNTP) testing led to a ring test conducted by four laboratories experienced in regulatory testing. Species selected had shown potential to meet validity criteria of emergence for TNTP studies in a previous evaluation of the 52 species. OECD 208 guideline conditions were applied, with and without seed pretreatments recommended to enhance germination. These species were Abutilon theophrasti (L.) Medic., Avena fatua L., Fallopia convolvulus (L.) Adans., Galium aparine L., Ipomoea hederacea (L.) Jacq. and Veronica persica Poir. Only I. hederacea met the validity criterion of 70% emergence in all laboratories and showed a low variability in biomass. Of the other species, none led to 70% emergence in all four laboratories. The recommended pretreatments did not have a major impact on emergence. Biomass was also investigated with A. theophrasti, A. fatua, Centaurea cyanus L., I. hederacea and Rumex crispus L. Variability of biomass, a key parameter in TNTP regulatory studies, exceeded normal biomass variability of crop species used for TNTP studies. The addition of a thin layer of quartz sand to the soil surface resulted in improved emergence of C. cyanus, G. aparine and V. persica; however, such a procedure, while routine in screening studies to improve germination, is a deviation from the TNTP guidelines. These initial studies indicate that some species could meet the emergence criteria for TNTP testing. However, there is a need for further studies on seed source, seed quality and conditions for uniform emergence before their use in routine regulatory testing.


Assuntos
Germinação/efeitos dos fármacos , Magnoliopsida/crescimento & desenvolvimento , Biomassa , Galium/crescimento & desenvolvimento , Herbicidas/efeitos adversos , Herbicidas/farmacologia , Ipomoea/crescimento & desenvolvimento , Malvaceae/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Especificidade da Espécie , Testes de Toxicidade , Estados Unidos , United States Environmental Protection Agency , Veronica/crescimento & desenvolvimento
7.
Sci Total Environ ; 574: 938-946, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27665453

RESUMO

Biological invasions are an important problem of human-induced changes at a global scale. Invasive plants can modify soil nutrient pools and element cycling, creating feedbacks that potentially stabilize current or accelerate further invasion, and prevent re-establishment of native species. The aim of this study was to compare the effects of Reynoutria japonica, Rudbeckia laciniata and Solidago gigantea, invading non-forest areas located within or outside river valleys, on soil physical and chemical parameters, including soil moisture, element concentrations, organic matter content and pH. Additionally, invasion effects on plant species number and total plant cover were assessed. The concentrations of elements in shoots and roots of invasive and native plants were also measured. Split-plot ANOVA revealed that the invasions significantly reduced plant species number, but did not affect most soil physical and chemical properties. The invasions decreased total P concentration and increased N-NO3 concentration in soil in comparison to native vegetation, though the latter only in the case of R. japonica. The influence of invasion on soil properties did not depend on location (within- or outside valleys). The lack of invasion effects on most soil properties does not necessarily imply the lack of influence of invasive plants, but may suggest that the direction of the changes varies among replicate sites and there are no general patterns of invasion-induced alterations for these parameters. Tissue element concentrations, with the exception of Mg, did not differ between invasive and native plants, and were not related to soil element concentrations.


Assuntos
Espécies Introduzidas , Polygonaceae/crescimento & desenvolvimento , Rudbeckia/crescimento & desenvolvimento , Solo/química , Solidago/crescimento & desenvolvimento , Raízes de Plantas , Polônia , Microbiologia do Solo
8.
PLoS One ; 11(9): e0162777, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27649564

RESUMO

Disturbance is a primary mechanism structuring ecological communities. However, human activity has the potential to alter the frequency and intensity of natural disturbance regimes, with subsequent effects on ecosystem processes. In Southern California, human development has led to increased fire frequency close to urban areas that can form a positive feedback with invasive plant spread. Understanding how abiotic and biotic factors structure post-fire plant communities is a critical component of post-fire management and restoration. In this study we considered a variety of mechanisms affecting post-fire vegetation recovery in Riversidean sage scrub. Comparing recently burned plots to unburned plots, we found that burning significantly reduced species richness and percent cover of exotic vegetation the first two years following a 100-hectare wildfire. Seed rain was higher in burned plots, with more native forb seeds, while unburned plots had more exotic grass seeds. Moreover, there were significant correlations between seed rain composition and plant cover composition the year prior and the year after. Collectively, this case study suggests that fire can alter community composition, but there was not compelling evidence of a vegetation-type conversion. Instead, the changes in the community composition were temporary and convergence in community composition was apparent within two years post-fire.


Assuntos
Asteraceae/crescimento & desenvolvimento , Conservação dos Recursos Naturais/métodos , Ecossistema , Incêndios , Polygonaceae/crescimento & desenvolvimento , Salvia/crescimento & desenvolvimento , California , Geografia , Atividades Humanas , Humanos , Espécies Introduzidas , Desenvolvimento Vegetal , Poaceae/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Especificidade da Espécie , Fatores de Tempo
9.
Sci Rep ; 6: 38320, 2016 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-27922131

RESUMO

The different responses of plant species to resource stress are keys to understand the dynamics of plant community in a changing environment. To test the hypothesis that nitrogen (N) increase would benefit N competitive species, rather than N stress-tolerant species, to compete with neighbours, we conducted an experiment with neighbour removal, N addition and soil moisture as treatments in an alpine grassland on the southeastern Tibetan Plateau. Both growths and competitive-response abilities (CRA, the ability to tolerate the inhibitory effects of neighbors) of Kobresia macrantha, Polygonum viviparum and Potentilla anserine in wet site were facilitated by N addition, conversely, both growths and CRA of Taraxacum mongolicum and Ligularia virgaurea were suppressed by N addition, indicating that the responses of CRA of target species under N addition were consistent with the N utilization strategies of them. Moreover, the facilitative effects of N addition on competitive-response abilities of Kobresia macrantha and Polygonum viviparum were not found at the dry site, illustrating that soil moisture can alter the changes of neighbour effects caused by N addition. Life strategy of dominant species in plant community on the undisturbed southeastern Tibetan Plateau may shift from N stress-tolerant to N competitive, if the N increases continuously.


Assuntos
Cyperaceae/efeitos dos fármacos , Nitrogênio/farmacologia , Polygonaceae/efeitos dos fármacos , Rosaceae/efeitos dos fármacos , Altitude , Cyperaceae/crescimento & desenvolvimento , Cyperaceae/metabolismo , Pradaria , Nitrogênio/metabolismo , Dispersão Vegetal/fisiologia , Polygonaceae/crescimento & desenvolvimento , Polygonaceae/metabolismo , Rosaceae/crescimento & desenvolvimento , Rosaceae/metabolismo , Solo/química , Tibet , Água/metabolismo , Água/farmacologia
10.
Acta sci., Biol. sci ; Acta sci., Biol. sci;43: e55992, 2021. graf, tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460996

RESUMO

The discontinuous seed hydration enables the acquisition of tolerance to environmental stresses, causing a stress imprint. It may modify metabolic patterns and lead to improved stress responses. This study aims to evaluate the effects of discontinuous hydration on germination and on seedling growth of Triplaris gardneriana Wedd. under intermittent drought. The seeds have gone through cycles (0, 1, 2 and 3) of hydration and dehydration (HD). The seedlings produced were subjected to water deficit (daily watering and intervals of seven and fourteen days between watering). Seed germinability parameters and, relative growth rate (RGR) of seedling, leaf area, dry matter yield and leaf relative water content (RWC) were evaluated. The HD cycles did not benefit germination, but two HD cycles induced a better biomass accumulation and increased leaf area in seedlings under moderate water deficit, while three HD cycles promoted an increase in RGR and influenced the RWC values. Severe stress affects seedling growth, but subjection to HD cycles minimizes the deleterious effects of drought, suggesting discontinuous hydration acts leading stress imprint in plants.


Assuntos
Desidratação , Hidratação , Polygonaceae/crescimento & desenvolvimento , Sementes/fisiologia
11.
Plant Biol (Stuttg) ; 6(2): 184-91, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15045670

RESUMO

The areal development of photosynthetic efficiency and growth patterns in expanding leaves of two different dicotyledonous species - Coccoloba uvifera and Sanchezia nobilis - was investigated by imaging both processes repeatedly over 32 days. Measurements were performed using combined imaging systems for chlorophyll fluorescence and growth, with the same spatial resolution. Significant differences in potential quantum yield of photosynthesis (F (v)/F (m)), a parameter indicating the functional status of photosystem II, were found between midvein and interveinal tissue. Although base-tip gradients and spatial patchiness were observed in the distribution of relative growth rate, neither midvein nor interveinal tissue showed such patterns in F (v)/F (m). In young leaves, F (v)/F (m) of the midvein was higher than F (v)/F (m) of interveinal tissue. This difference declined gradually with time, and upon cessation of growth, F (v)/F (m) of interveinal regions exceeded those of midvein tissue. Images of chlorophyll fluorescence quenching showed that DeltaF/F (m)' in the different tissues correlated with F (v)/F (m), indicating that, in these uniformly illuminated leaves, transitions in photosynthetic electron transport activity follow those of predawn quantum efficiency. We explore the implications of these observations during leaf development, discuss effects of sucrose delivery from veins to interveinal areas on relative rates of photosynthetic development in these tissues, and propose that the initially higher photosynthetic activity in the midvein compared to the intervein tissues may supply carbohydrates and energy for leaf growth processes.


Assuntos
Acanthaceae/crescimento & desenvolvimento , Fotossíntese/fisiologia , Folhas de Planta/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Clorofila/metabolismo , Folhas de Planta/anatomia & histologia
12.
Pest Manag Sci ; 57(12): 1161-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11802605

RESUMO

Previous work had shown that the sulfonylurea herbicide chlorsulfuron affected the survival of a herbivorous insect species dwelling on a sub-lethally exposed host plant. Further experiments have been conducted to establish whether this negative effect was a single occurrence characteristics for the specific insect-plant interaction and the specific herbicide tested. Three insect-plant interactions were tested for the effects of selected sulfonylurea herbicides, i.e. metsulfuron-methyl, chlorsulfuron and tribenuron-methyl. The species pairs tested were Pieris brassicae/Brassica napus, Gastrophysa polygoni/Fallopia convolvulus and Sitobium avenae/Triticum aestivium. No significant effects on survival and relative growth rate of P brassicae or G polygoni were found when treating the host plants with sulfonylurea herbicides. However, the host plants had a significantly reduced root and shoot growth rate when treated with herbicide. Treating T aestivium with the recommended field rate of metasulfuron-methyl did not cause any change in development time, growth rate or fecundity of S avenae feeding on the host plants. The data presented suggest that the increased mortality observed for G polygoni larvae feeding on chlorsulfuron-treated host plants observed earlier was characteristic for this herbicide and for the specific plant-insect interaction only.


Assuntos
Sulfonatos de Arila/farmacologia , Herbicidas/farmacologia , Insetos/efeitos dos fármacos , Plantas/efeitos dos fármacos , Sulfonamidas , Triazinas/farmacologia , Análise de Variância , Animais , Afídeos/efeitos dos fármacos , Afídeos/fisiologia , Brassica/efeitos dos fármacos , Brassica/crescimento & desenvolvimento , Brassica/parasitologia , Borboletas/efeitos dos fármacos , Borboletas/fisiologia , Besouros/efeitos dos fármacos , Besouros/fisiologia , Relação Dose-Resposta a Droga , Interações Hospedeiro-Parasita/efeitos dos fármacos , Insetos/fisiologia , Desenvolvimento Vegetal , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/parasitologia , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/parasitologia , Plantas/parasitologia , Polygonaceae/efeitos dos fármacos , Polygonaceae/crescimento & desenvolvimento , Polygonaceae/parasitologia , Testes de Toxicidade , Triticum/efeitos dos fármacos , Triticum/crescimento & desenvolvimento , Triticum/parasitologia
13.
Zhong Yao Cai ; 21(3): 109-10, 1998 Mar.
Artigo em Zh | MEDLINE | ID: mdl-12567935

RESUMO

In the present thesis, suitable medium for callus inducement and relationship between culture time and callus growth of Poligonum multiflorum were studied by mono-factorial and orthogonal design test. The experiments showed that the best medium for callus inducement was MS + 2,4-D 1 mg/L + 6-BA 1 mg/L + IBA 0.5 mg/L, dark culture was better than light culture, callus grew fast when it was cultured 12 days, whole plant could be induced by callus, the induce rate was 95%.


Assuntos
Reguladores de Crescimento de Plantas/farmacologia , Plantas Medicinais/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Meios de Cultura , Técnicas de Cultura , Hormônios , Luz
14.
Zhong Yao Cai ; 20(5): 217-8, 1997 May.
Artigo em Zh | MEDLINE | ID: mdl-12572459

RESUMO

The experiments of some cultivated medthods of Polygonum multiforum show that the direct sowing of seeds is better than the cuttage, the index of reproduction and yield are higher, and the cultivated method can decrease expense. To cultivation period of 5 years, high yield and excellent qualty is available.


Assuntos
Plantas Medicinais/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Temperatura , Fatores de Tempo
15.
Environ Entomol ; 43(4): 923-31, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25182614

RESUMO

Rhinoncomimus latipes Korotyaev (Coleoptera: Curculionidae), a biological control agent of mile-a-minute weed, Persicaria perfoliata (L.) H. Gross, has been mass reared with no infusion of new genetic material for 8-9 yr (at least 24-36 generations), while insects from the same genetic stock have been subject to field conditions in North America for that same period of time. Our main objective was to compare the laboratory population with the field population (and in 1 yr with a Chinese field population) to determine whether genetic changes had occurred, especially ones that may reduce the effectiveness of the laboratory population when released in the field. The laboratory insects laid more eggs and had reduced survival compared with field weevils in several comparisons, and had reduced responsiveness to cues that induce reproductive diapause. Exposure to older plants had the greatest effect on induction of reproductive diapause in both laboratory and field weevils, with effects of daylength and temperature less pronounced. At least a portion of the laboratory weevil population overwintered successfully. Results suggest that it is not necessary to add wild-type genetic material to the rearing colony at this time.


Assuntos
Agentes de Controle Biológico , Aptidão Genética , Polygonaceae/crescimento & desenvolvimento , Controle de Plantas Daninhas , Gorgulhos/fisiologia , Animais , China , Temperatura Baixa , Diapausa de Inseto , Meio Ambiente , Comportamento Alimentar , Feminino , Larva/genética , Larva/fisiologia , Larva/efeitos da radiação , Masculino , Fotoperíodo , Estados Unidos , Gorgulhos/genética , Gorgulhos/efeitos da radiação
16.
Plant Biol (Stuttg) ; 15(6): 1001-12, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23252825

RESUMO

It has been suggested that architectural plasticity in shoot size and number allows plants to manage environmental risks. Simpler structures require shorter development times and fewer resources, which secure minimal fitness even under risky and unfavourable conditions. Here we tested the hypothesis that the magnitude of such architectural plasticity depends on the species' developmental strategy. Specifically, species with late reproduction were expected to express the highest levels of architectural plasticity in response to environmental cues predicting high probability of abrupt deterioration in growth conditions. This hypothesis was tested by comparing Mediterranean and semi-arid populations of three species, which differed in growth strategy: Trifolium purpureum, a determinate and late flowerer, and Emex spinosa and Hippocrepis unisiliquosa that flower indeterminately throughout the season. All plants were exposed to varying levels of water availability and competition, but only T. purpureum displayed plastic architectural responsiveness to the experimental manipulations. In contrast, the early and extended step-by-step flowering of both E. spinosa and H. unisiliquosa reflected a relatively deterministic bet-hedging reproductive schedule, whereby minimum fitness is secured even under adverse conditions. These two opposing strategies gave contrasting results, with E. spinosa and H. unisiliquosa displaying reduced efficiency under favourable conditions under which T. purpureum had the highest reproductive efficiency. The evolutionary interplay between deterministic risk-averse and plastic risk-prone growth strategies might reflect contrasts in the probability and severity of environmental risks, and the costs of missed opportunities.


Assuntos
Fabaceae/anatomia & histologia , Polygonaceae/anatomia & histologia , Evolução Biológica , Biomassa , Meio Ambiente , Fabaceae/crescimento & desenvolvimento , Flores/anatomia & histologia , Flores/crescimento & desenvolvimento , Região do Mediterrâneo , Fenótipo , Brotos de Planta/anatomia & histologia , Brotos de Planta/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Reprodução , Estações do Ano , Fatores de Tempo , Trifolium/anatomia & histologia , Trifolium/crescimento & desenvolvimento
17.
Ying Yong Sheng Tai Xue Bao ; 23(9): 2377-82, 2012 Sep.
Artigo em Zh | MEDLINE | ID: mdl-23285991

RESUMO

In order to understand the effects of thinning on the growth of Calligonum arborescens and the soil water-salt distribution in Tarim Desert Highway shelterbelt, a thinning experiment was conducted on an aged and declined C. arborescens woodland in a demonstration section of the shelterbelt, with the growth of C. arborescens and the soil water-salt distribution monitored. Thinning had no effects on the phenophase of C. arborescens, but after thinning, the growth of the current year plant height, crown width, ground diameter, and new branch length of reserved trees was larger than that of the control, and the increment was in the order of planting space 2 mx 1 m > 1 m x 1 m > the control, with significant differences among the treatments. The assimilation branch surface area in treatments 2 mx 1 m and 1 m x 1 m were 5.97 m2 and 5.22 m2 per plant, respectively, being significantly larger than the control (3.1 m2 per plant). The soil moisture content in 0-160 cm layer was significantly higher in treatments 2 m x 1 m and 1 mx 1 m than in the control, and increased obviously with thinning intensity. The soil salt content was in the order of control > planting space 1 m x 1 m > 2 m x 1 m, and the differences among the treatments were significant. It was suggested that the best reserved plant density after thinning was planting space 2 m x 1 m.


Assuntos
Clima Desértico , Polygonaceae/crescimento & desenvolvimento , Sais/análise , Solo/química , Água/análise , China , Ecossistema , Agricultura Florestal/métodos , Polygonaceae/metabolismo , Cloreto de Sódio/análise
18.
Ying Yong Sheng Tai Xue Bao ; 23(6): 1462-8, 2012 Jun.
Artigo em Zh | MEDLINE | ID: mdl-22937631

RESUMO

In order to ensure the stability and sustainability of the Calligonum mongolicum shelterbelt along Tarim Desert Highway, the aged C. mongolicum was stumped to investigate its growth and soil moisture and salt distribution. After stumping twice, C. mongolicum grew rapidly in its height, crown width, maximum basal diameter, and sprout number. Three years after stumping, the average height of the sprouts exceeded the control (no stumping), and the crown width and maximum basal diameter was 92.0% and 73.0% of the control, respectively. The fresh mass of the branches and assimilating branches, their dry mass, and the total fresh mass and dry mass of the aboveground parts reached 80.0%, 115.0%, 80.0%, 116.0%, 93.5%, and 88.0% of the control, respectively. Four years after stumping, the aboveground biomass surpassed the control. Comparing with the control, stumping increased the soil moisture content significantly and decreased the soil salt concentration. It was suggested that, to stump the aged C. mongolicum repeatedly could increase the soil moisture content and decrease the soil salt concentration in root zone, and effectively promote the rejuvenation and renewing of C. mongolicum.


Assuntos
Ecossistema , Polygonaceae/crescimento & desenvolvimento , Sais/análise , Solo/análise , Água/análise , China , Clima Desértico , Monitoramento Ambiental , Polygonaceae/metabolismo
19.
Environ Entomol ; 39(3): 849-55, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20550798

RESUMO

Fluctuating asymmetry (FA) represents small, random variations from the symmetric bilateral pattern, and it is a frequently used measurement of plant and animal stresses. Some studies have shown a relationship between FA and herbivory, suggesting that FA might be a reliable indicator of plant quality and plant susceptibility to herbivore attack. In this study, we investigated the relationship between leaf FA of Coccoloba cereifera Schwacke (Polygonaceae) and the pattern of attack by the scale insect Abgrallaspis cyanophylly Signoret (Hemiptera: Diaspididae). Thirty individuals of C. cereifera were marked and followed during 2007 in southeastern Brazil, and all leaves of three shoots per plant were sampled, numbered, and categorized as young, mature, or senescent. We measured right and left widths of all leaves after digitizing the images to determine levels of FA for each leaf sampled per plant. Individuals of A. cyanophylli were counted using a stereoscope in the laboratory to determine infestation levels. Leaves of C. cereifera exhibited true patterns of FA, as shown by the normal distribution of asymmetry values. We observed high variation in attack rates by A. cyanophylly among C. cereifera individuals, with 43.3% of plants with no insects, whereas others exhibited up to 23,000 insects. No statistically significant relationship was observed between variation in FA and variation in A. cyanophylli among plants. These results suggest that FA cannot be used as an indicator of plant quality and susceptibility to herbivore attack but suggest that herbivores themselves might act as plant stressors.


Assuntos
Preferências Alimentares , Hemípteros , Polygonaceae/parasitologia , Estresse Fisiológico , Animais , Folhas de Planta/química , Folhas de Planta/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento
20.
Am J Chin Med ; 38(3): 473-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20503466

RESUMO

Fallopia multiflora (Thunb.) Harald, a traditional Chinese medicinal plant, is used in treating dizziness. In this study, the samples of F. multiflora from ten different locations were collected, and five bioactive components (2, 3, 5, 4'-tetrahydroxystilbene-2-O-beta-D-glucoside, emodin, emodin-8-O-beta-D-glucoside, physcion and physcion-8-O-beta-D-glucoside) were quantified by high performance liquid chromatography. The correlations between 17 environmental factors and 5 bioactive components were analyzed. The results showed that the highest contents of bioactive components were in samples from Deqing, and the lowest in samples from Tianyang, which indicated that the quality of F. multiflora grown in Deqing was superior, while that grown in Tianyang was inferior. Emodin content was negatively correlated with the average temperature in January (p < 0.01) and the accumulated temperature (p < 0.01). Physician content was also negatively correlated with the average temperature in January (P < 0.01), the accumulated temperature (p < 0.05) and the organic matter (p < 0.05). However, emodin was positively correlated with the soil available K (p < 0.05) and Zn (p < 0.01). The results of stepwise regression showed that the accumulated temperature was the main factor influencing the contents of emodin and physcion. However, none of the environmental factors had significant correlation with 2, 3, 5, 4'-tetrahydroxystilbene-2-O-beta-D-glucoside, emodin-8- O-beta-D-glucoside and physcion-8-O-beta-D-glucoside. In conclusion, some environmental factors have significant influence on the content of dissociated anthraquinones, while some have no influence on that of combined anthraquinones.


Assuntos
Meio Ambiente , Extratos Vegetais/análise , Raízes de Plantas/química , Polygonaceae/química , Antraquinonas/análise , China , Cromatografia Líquida de Alta Pressão , Ecossistema , Emodina/análogos & derivados , Emodina/análise , Geografia , Glucosídeos/análise , Extratos Vegetais/química , Raízes de Plantas/crescimento & desenvolvimento , Polygonaceae/crescimento & desenvolvimento , Solo/análise
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