929 resultados para Ilex paraguariensis


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The aim of the present study was to analyse whether offspring of mature Quercus ilex trees grown under life-long elevated pCO2 show alterations in the physiological response to elevated pCO2 in comparison with those originating from mature trees grown at current ambient pCO2. To investigate changes in C- (for changes in photosynthesis, biomass and lignin see Polle, McKee & Blaschke Plant, Cell and Environment 24, 1075–1083, 2001), N-, and S-metabolism soluble sugar, soluble non-proteinogenic nitrogen compounds (TSNN), nitrate reductase (NR), thiols, adenosine 5′-phosphosulphate (APS) reductase, and anions were analysed. For this purpose Q. ilex seedlings were grown from acorns of mother tree stands at a natural spring site (elevated pCO2) and a control site (ambient pCO2) of the Laiatico spring, Central Italy. Short-term elevated pCO2 exposure of the offspring of control oaks lead to higher sugar contents in stem tissues, to a reduced TSNN content in leaves, and basipetal stem tissues, to diminished thiol contents in all tissues analysed, and to reduced APS reductase activity in both, leaves and roots. Most of the components of C-, N- and S-metabolism including APS reductase activity which were reduced due to short-term elevated pCO2 exposure were recovered by life-long growth under elevated pCO2 in the offspring of spring oaks. Still TSNN contents in phloem exudates increased, nitrate contents in lateral roots and glutathione in leaves and phloem exudates remained reduced in these plants. The present results demonstrated that metabolic adaptations of Q. ilex mother trees to elevated pCO2 can be passed to the next generation. Short- and long-term effects on source-to-sink relation and physiological and genetic acclimation to elevated pCO2 are discussed.

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Von Dr. Fr. Westhoff

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Plant trichomes play important protective functions and may have a major influence on leaf surface wettability. With the aim of gaining insight into trichome structure, composition and function in relation to water-plant surface interactions, we analyzed the adaxial and abaxial leaf surface of Quercus ilex L. (holm oak) as model. By measuring the leaf water potential 24 h after the deposition of water drops on to abaxial and adaxial surfaces, evidence for water penetration through the upper leaf side was gained in young and mature leaves. The structure and chemical composition of the abaxial (always present) and adaxial (occurring only in young leaves) trichomes were analyzed by various microscopic and analytical procedures. The adaxial surfaces were wettable and had a high degree of water drop adhesion in contrast to the highly unwettable and water repellent abaxial holm oak leaf sides. The surface free energy, polarity and solubility parameter decreased with leaf age, with generally higher values determined for the abaxial sides. All holm oak leaf trichomes were covered with a cuticle. The abaxial trichomes were composed of 8% soluble waxes, 49% cutin, and 43% polysaccharides. For the adaxial side, it is concluded that trichomes and the scars after trichome shedding contribute to water uptake, while the abaxial leaf side is highly hydrophobic due to its high degree of pubescence and different trichome structure, composition and density. Results are interpreted in terms of water-plant surface interactions, plant surface physical-chemistry, and plant ecophysiology.

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La encina (Quercus ilex L.) es una de las especies forestales mediterráneas más importantes. Constituye gran parte del estrato arbóreo de dehesas o montados, produce bellota como alimento del ganado y establece simbiosis con hongos micorrizógenos de gran valor económico. La encina está considerada como una especie recalcitrante en términos de conservación de semillas y capacidad morfogénica, lo que dificulta los programas de conservación de recursos genéticos y la mejora de la especie. La propagación vegetativa es una potente herramienta de los programas de mejora, por lo que es preciso desarrollar protocolos de regeneración somática en encina. La embriogénesis somática está considerada como la modalidad más adecuada de regeneración basada en técnicas de cultivo de tejidos vegetales utilizada en biotecnología forestal. Este trabajo se centra en el estudio de determinados aspectos de la embriogénesis somática para la regeneración clonal de encinas adultas. La memoria de esta tesis se ha dividido en capítulos que se corresponden con diferentes aspectos del sistema embriogénico. La embriogénesis somática se indujo en tegumentos maternos de óvulos en desarrollo procedentes de bellotas inmaduras de encinas adultas. A pesar de las bajas frecuencias de inducción, las líneas embriogénicas generadas se amplificaron mediante embriogénesis secundaria observándose cierta pérdida de la capacidad de diferenciación con el tiempo. Tanto el genotipo como la formulación del medio de cultivo influyeron en la respuesta embriogénica, concluyendo que la formulación de macronutrientes de Schenk y Hildebrant del medio sin reguladores de crecimiento fue la combinación más efectiva en la inducción. Los resultados sugirieron la existencia de una ventana en el desarrollo del óvulo más sensible a la inducción. El genotipo in[luyó en la capacidad proliferativa de los cultivos y en la conversión de los embriones somáticos, que se incrementó suplementando el medio con ácido indol-3-butírico y 6-benciladenina. El cultivo en medio líquido de líneas embriogénicas en condiciones de inmersión transitoria incrementó el crecimiento, dependiendo del genotipo, con respecto al cultivo en medio semisólido. Sin embargo, no mejoró la capacidad de diferenciar embriones cotiledonares aislados. Se estableció un protocolo de inicio y mantenimiento de cultivos en suspensión para varias líneas embriogénicas mediante inoculación en alta densidad de agregados embrionarios procedentes del medio semisólido. Para evitar la pérdida de vigor y la capacidad morfogénica debida al cultivo prolongado se desarrolló un protocolo de crioconservación de líneas embriogénicas mediante vitrificación. Al determinar la influencia de los agentes crioprotectores antes y después de su inmersión en nitrógeno líquido se concluyó que las respuestas de capacidad de crecimiento y de diferenciación del material embriogénico son independientes, además de estar bajo influencia del genotipo y el tipo de material crioconservado. La combinación de sacarosa y PVS2 previa a la inmersión en nitrógeno líquido proporcionó la mayor tasa de recuperación. Cuando las líneas fueron crioconservadas 30 días la capacidad de diferenciación se perdió en todas ellas. El análisis de SSR detectó variación somaclonal en el material crioconservado a corto plazo. SSR y RAPD mostraron importantes diferencias genéticas entre los árboles donantes y el material embriogénico que dependieron del genotipo. El grado de detección dependió del marcador empleado. Ambos marcadores revelaron baja inestabilidad intraclonal. Los RAPD revelaron variación genética intra-individuo en las encinas donantes. Se discuten la variación genética pre-existente en encina, su aparición durante las primeras fases de la inducción de embriogénesis, y la presencia de tejidos provenientes de la fertilización en el explanto materno. Esto hace preciso definir la identidad genética del material donante y acometer ensayos de detección precoz de variación somaclonal. ABSTRACT Holm oak (Quercus ilex L.) is one of the most important Mediterranean forest species. It conforms the tree layer of dehesas or montados, it produces acorns to feed the livestock and it establishes symbiosis with profitable mycorrhizal fungi. Holm oak is considered as recalcitrant species in terms of seed conservation and morphogenic capacities, which complicates the development of genetic conservation and improvement programs. Vegetative propagation is one of the mightiest tools for breeding programs therefore; developing protocols for clonal regeneration of holm oak is essential. Somatic embryogenesis is considered the best tissue culture-based way of plant regeneration in forest biotechnology. The present study is focused on the study of certain aspects of somatic embryogenesis for clonal regeneration of mature holm oak. This thesis manuscript is divided into several chapters that match with different aspects of the embryogenic system. Somatic embryogenesis induction was achieved on maternal teguments of developing ovules from immature acorns of adult holm oak trees. Despite the low induction frequencies, the generated embryogenic lines were amplified by secondary embryogenesis. A decline in the differentiation capacity over time was also observed. It was concluded that both genotype and culture media formulation influenced the embryogenic response, being the Schenk and Hildebrandt´s macronutrients formulation from culture medium and the lack of plant growth regulators the most effective combination for the induction of the embryogenic response. It has been suggested the existence of a developmental window in which ovules are prone to induction. Genotype influenced the proliferation capacity and the plant conversion of somatic embryos, which was also favoured by the presence of indol-3-butyric acid and 6-bencyladenine. The use of temporary immersion systems as proliferation in liquid culture of the embryogenic lines increased the growth depending on genotype, when compared to semisolid cultures. However, it did not improve the differentiation of single cotyledonary embryos. A protocol for the initiation and maintenance of embryogenic suspension cultures was established for several embryogenic lines with highly dense inoculi of embryogenic clusters from proliferating semisolid cultures. In order to avoid the loss of vigour and morphogenic ability of embryogenic lines due to prolonged cultures, a cryopreservation protocol for embryogenic lines of holm oak has been developed. During the determination of the influence of cryoprotective agents on the growth and differentiation capacities before and after liquid nitrogen immersion, it was concluded that both responses were independent from each other and also under the influence of genotype and the type of cryopreserved material. The combination of sucrose and PVS2 prior liquid nitrogen immersion provided higher recovery rates. When the same embryogenic lines were cryopreserved for 30 days, none was able to differentiate. The SSRs analysis of the short-term cryopreserved material detected somaclonal variation. Both SSR and RAPD markers showed high sensitivity to detect genetic differences between the donor trees and the generated embryogenic material. Nevertheless, the degree of instability detection depended on the marker. The SSR analysis indicated a relationship between genotype, the studied loci and the located polymorphisms. Also, both markers revealed low intraclonal genetic variation. The RAPD detected genetic variation within the donor trees. The presence of pre-existent genetic variation within mature trees, in addition to its occurrence during the early stages of the embryogenic induction, and the presence of tissues of fertilisation origin within the maternal explants are all discussed. Nonetheless, the determination of the genetic identity of donor material is required, in addition to early detection methods of somaclonal variation.

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La encina (Quercus ilex L.) es una de las especies forestales mediterráneas más importantes. Constituye gran parte del estrato arbóreo de dehesas o montados, produce bellota como alimento del ganado y establece simbiosis con hongos micorrizógenos de gran valor económico. La encina está considerada como una especie recalcitrante en términos de conservación de semillas y capacidad morfogénica, lo que dificulta los programas de conservación de recursos genéticos y la mejora de la especie. La propagación vegetativa es una potente herramienta de los programas de mejora, por lo que es preciso desarrollar protocolos de regeneración somática en encina. La embriogénesis somática está considerada como la modalidad más adecuada de regeneración basada en técnicas de cultivo de tejidos vegetales utilizada en biotecnología forestal. Este trabajo se centra en el estudio de determinados aspectos de la embriogénesis somática para la regeneración clonal de encinas adultas. La memoria de esta tesis se ha dividido en capítulos que se corresponden con diferentes aspectos del sistema embriogénico. La embriogénesis somática se indujo en tegumentos maternos de óvulos en desarrollo procedentes de bellotas inmaduras de encinas adultas. A pesar de las bajas frecuencias de inducción, las líneas embriogénicas generadas se amplificaron mediante embriogénesis secundaria observándose cierta pérdida de la capacidad de diferenciación con el tiempo. Tanto el genotipo como la formulación del medio de cultivo influyeron en la respuesta embriogénica, concluyendo que la formulación de macronutrientes de Schenk y Hildebrant del medio sin reguladores de crecimiento fue la combinación más efectiva en la inducción. Los resultados sugirieron la existencia de una ventana en el desarrollo del óvulo más sensible a la inducción. El genotipo in[luyó en la capacidad proliferativa de los cultivos y en la conversión de los embriones somáticos, que se incrementó suplementando el medio con ácido indol-3-butírico y 6-benciladenina. El cultivo en medio líquido de líneas embriogénicas en condiciones de inmersión transitoria incrementó el crecimiento, dependiendo del genotipo, con respecto al cultivo en medio semisólido. Sin embargo, no mejoró la capacidad de diferenciar embriones cotiledonares aislados. Se estableció un protocolo de inicio y mantenimiento de cultivos en suspensión para varias líneas embriogénicas mediante inoculación en alta densidad de agregados embrionarios procedentes del medio semisólido. Para evitar la pérdida de vigor y la capacidad morfogénica debida al cultivo prolongado se desarrolló un protocolo de crioconservación de líneas embriogénicas mediante vitrificación. Al determinar la influencia de los agentes crioprotectores antes y después de su inmersión en nitrógeno líquido se concluyó que las respuestas de capacidad de crecimiento y de diferenciación del material embriogénico son independientes, además de estar bajo influencia del genotipo y el tipo de material crioconservado. La combinación de sacarosa y PVS2 previa a la inmersión en nitrógeno líquido proporcionó la mayor tasa de recuperación. Cuando las líneas fueron crioconservadas 30 días la capacidad de diferenciación se perdió en todas ellas. El análisis de SSR detectó variación somaclonal en el material crioconservado a corto plazo. SSR y RAPD mostraron importantes diferencias genéticas entre los árboles donantes y el material embriogénico que dependieron del genotipo. El grado de detección dependió del marcador empleado. Ambos marcadores revelaron baja inestabilidad intraclonal. Los RAPD revelaron variación genética intra-individuo en las encinas donantes. Se discuten la variación genética pre-existente en encina, su aparición durante las primeras fases de la inducción de embriogénesis, y la presencia de tejidos provenientes de la fertilización en el explanto materno. Esto hace preciso definir la identidad genética del material donante y acometer ensayos de detección precoz de variación somaclonal. ABSTRACT Holm oak (Quercus ilex L.) is one of the most important Mediterranean forest species. It conforms the tree layer of dehesas or montados, it produces acorns to feed the livestock and it establishes symbiosis with profitable mycorrhizal fungi. Holm oak is considered as recalcitrant species in terms of seed conservation and morphogenic capacities, which complicates the development of genetic conservation and improvement programs. Vegetative propagation is one of the mightiest tools for breeding programs therefore; developing protocols for clonal regeneration of holm oak is essential. Somatic embryogenesis is considered the best tissue culture-based way of plant regeneration in forest biotechnology. The present study is focused on the study of certain aspects of somatic embryogenesis for clonal regeneration of mature holm oak. This thesis manuscript is divided into several chapters that match with different aspects of the embryogenic system. Somatic embryogenesis induction was achieved on maternal teguments of developing ovules from immature acorns of adult holm oak trees. Despite the low induction frequencies, the generated embryogenic lines were amplified by secondary embryogenesis. A decline in the differentiation capacity over time was also observed. It was concluded that both genotype and culture media formulation influenced the embryogenic response, being the Schenk and Hildebrandt´s macronutrients formulation from culture medium and the lack of plant growth regulators the most effective combination for the induction of the embryogenic response. It has been suggested the existence of a developmental window in which ovules are prone to induction. Genotype influenced the proliferation capacity and the plant conversion of somatic embryos, which was also favoured by the presence of indol-3-butyric acid and 6-bencyladenine. The use of temporary immersion systems as proliferation in liquid culture of the embryogenic lines increased the growth depending on genotype, when compared to semisolid cultures. However, it did not improve the differentiation of single cotyledonary embryos. A protocol for the initiation and maintenance of embryogenic suspension cultures was established for several embryogenic lines with highly dense inoculi of embryogenic clusters from proliferating semisolid cultures. In order to avoid the loss of vigour and morphogenic ability of embryogenic lines due to prolonged cultures, a cryopreservation protocol for embryogenic lines of holm oak has been developed. During the determination of the influence of cryoprotective agents on the growth and differentiation capacities before and after liquid nitrogen immersion, it was concluded that both responses were independent from each other and also under the influence of genotype and the type of cryopreserved material. The combination of sucrose and PVS2 prior liquid nitrogen immersion provided higher recovery rates. When the same embryogenic lines were cryopreserved for 30 days, none was able to differentiate. The SSRs analysis of the short-term cryopreserved material detected somaclonal variation. Both SSR and RAPD markers showed high sensitivity to detect genetic differences between the donor trees and the generated embryogenic material. Nevertheless, the degree of instability detection depended on the marker. The SSR analysis indicated a relationship between genotype, the studied loci and the located polymorphisms. Also, both markers revealed low intraclonal genetic variation. The RAPD detected genetic variation within the donor trees. The presence of pre-existent genetic variation within mature trees, in addition to its occurrence during the early stages of the embryogenic induction, and the presence of tissues of fertilisation origin within the maternal explants are all discussed. Nonetheless, the determination of the genetic identity of donor material is required, in addition to early detection methods of somaclonal variation.

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Article New Forests November 2015, Volume 46, Issue 5, pp 869-883 First online: 17 June 2015 Establishing Quercus ilex under Mediterranean dry conditions: sowing recalcitrant acorns versus planting seedlings at different depths and tube shelter light transmissionsJuan A. OlietAffiliated withDepartamento de Sistemas y Recursos Naturales, E.T.S. Ingenieros de Montes, Universidad Politécnica de Madrid Email author View author's OrcID profile , Alberto Vázquez de CastroAffiliated withDepartamento de Sistemas y Recursos Naturales, E.T.S. Ingenieros de Montes, Universidad Politécnica de Madrid, Jaime PuértolasAffiliated withLancaster Environment Centre, Lancaster University $39.95 / €34.95 / £29.95 * Rent the article at a discount Rent now * Final gross prices may vary according to local VAT. Get Access AbstractSuccess of Mediterranean dry areas restoration with oaks is a challenging goal. Testing eco-techniques that mimic beneficial effects of natural structures and ameliorate stress contributes to positive solutions to overcoming establishment barriers. We ran a factorial experiment in a dry area, testing two levels of solid wall transmission of tube shelters (60 and 80 %) plus a control mesh, and two depths (shallow and 15 cm depth) of placing either planted seedlings or acorns of Quercus ilex. Microclimate of the planting or sowing spots was characterized by measuring photosynthetically active radiation, temperature and relative humidity. Plant response was evaluated in terms of survival, phenology, acorn emergence and photochemical efficiency (measured through chlorophyll fluorescence). We hypothesize that tube shelters and deep planting improve Q. ilex post-planting and sowing performance because of the combined effects of reducing excessive radiation and improving access to moist soil horizons. Results show that temperature and PAR was reduced, and relative humidity increased, in deep spots. Midsummer photochemical efficiency indicates highest level of stress for oaks in 80 % light transmission shelter. Optimum acorn emergence in spring was registered within solid wall tree shelters, and maximum summer survival of germinants and of planted seedlings occurred when acorns or seedlings were placed at 15 cm depth irrespectively of light transmission of shelter. Survival of germinants was similar to that of planted seedlings. The importance of techniques to keep high levels of viability after sowing recalcitrant seeds in the field is emphasized in the study

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Quercus ilex L. leaves emit terpenes but do not have specialized structures for terpene storage. We exploited this unique feature to investigate terpene biosynthesis in intact leaves of Q. ilex. Light induction allowed us to distinguish three classes of terpenes: (i) a rapidly induced class including alpha-pinene; (ii) a more slowly induced class, including cis-beta-ocimene; and (iii) the most slowly induced class, including 3-methyl-3-buten-1-ol. Using 13C, we found that alpha-pinene and cis-beta-ocimene were labeled quickly and almost completely while there was a delay before label appeared in linalool and 3-methyl-3-buten-1-ol. The acetyl group of 3-methyl-3-buten-1-yl acetate was labeled quickly but label was limited to 20% of the moiety. It is suggested that the ocimene class of monoterpenes is made from one or more terpenes of the alpha-pinene class and that both classes are made entirely from reduced carbon pools inside the chloroplasts. Linalool and 3-methyl-3-buten-1-ol are made from a different pool of reduced carbon, possibly in nonphotosynthetic plastids. The acetyl group of the 3-methyl-3-buten-1-yl acetate is derived mostly from carbon that does not participate in photosynthetic reactions. Low humidity and prolonged exposure to light favored ocimenes emission and induced linalool emission. This may indicate conversion between terpene classes.

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Purpose: To evaluate the leishmanicidal and cytotoxic activity of alcohol and non-alcohol extracts and saponins from Ilex laurina . Methods: Extracts were obtained by percolation with solvents of different polarities: hexane, dichloromethane, ethyl acetate and ethanol. The ethyl acetate extract was subjected to silica gel column chromatography eluting with a step gradient of dichloromethane-methanol. All products were evaluated in vitro for leishmanicidal activity against amastigotes of leishmania panamensis and cytotoxicity on U- 937 cells. Results: Two saponins were isolated from the ethyl acetate extract. The ethyl acetate extract showed high leishmanicidal activity against intracellular amastigotes of L. panamensis (EC50, 7.5 ± 1.5 μg/mL) and low activity against axenic amastigotes (EC50, 52.8 ±1.6 μg/mL); this extract showed also high cytotoxicity (LC50, 57.7 ± 12.1 μg/mL). Saponin 2 exhibited high activity against intracellular amastigotes (EC50, 5.9 ± 0.5 μg/mL) but also showed high cytotoxicity on U-937 cells (EC50, 25.7 ± 6.1 μg/mL). This compound showed similar leishmanicidal activity and cytotoxicity to meglumine antimoniate and amphotericin B, respectively, drugs currently used for the treatment of leishmaniasis. Conclusions: Based on these results, Ilex laurina is a potential source of compounds that can lead to the development of new therapeutic alternatives against leishmaniasis.

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Homenaje a Ignacio Barandiarán Maestu / coord. por Javier Fernández Eraso, Juan Santos Yanguas

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刺叶栎( Quercus ilex L.)是地中海的常绿树种,属于古老的第三纪植物区系成份。本文根据苏黎世——蒙特利尔学派的植被学基本原理,全面地研究了分布在整个威尼托(Veneto)大区的剌叶栎林,详细研究刺叶栎林的群落组成、结构及类型划分。同时,对威尼托的刺叶栎林同北京山区的栎林进行了比较研究。最后,着重研究了威尼托刺叶栎林的生物多样性。 威尼托的刺叶栎林主要分布在亚得里亚海沿岸(包括Foci del Tagtiamento和Bosco Nordio e Rosolina Mare两地)、Lago di Garda和Colli Euganei。 在气候上,亚得里亚海沿岸属于半地中海气候。加尔达湖区域(Laqo di Garda)则是接近欧洲中部的大陆性气候,且维持半地中海的气候特点。Co t l i Euganei是这两地气候的过渡类型,且更接近亚得里亚海沿岸的类型。 在亚得里亚海沿岸的刺叶栎林可以分为三类,第一类(I)是一些矮树丛,这是Fraxinus ornus和Quercus ilex混交林的前身,较干旱。第二类群落(II)缺少乔木层,灌木层是由一些盖度不大的刺叶栎代替,更干旱。第三类群落(Ⅲ)是一群在外貌上相同的成熟群落.Fraxinus ornus和Quercus ilex得到充分发展,较中生。 在加尔达湖区的刺叶栎林可划分为三类。第一类群落(I)代表一组耐旱、开敞的矮树丛,含有Sesterio Variae-Ostryelum群丛的特征种,这一类可划分为SesLerio Variae-Ostryetum群 丛,土壤贫脊和干旱。第二类群落(Ⅱ)代表一类较郁闭的矮树丛,含有较多的Prunetalia群落目的成份,土壤较贫脊。第三类群(Ⅲ)代表一类郁闭的群落,乔木具有很大的密度因而林下灌木不能充分发展。SesLerio Variae-Ostryetum群丛和Prunetalia群落目的成份均不多。 在Colli Euganei的刺叶栎林可划分为二类。第一类群落(I)是一些不郁闲的矮树林组成。大体上分为地中海旱生栎林和地中海假灌丛。第二类群落(II)代表了较中生状态的植被,刺叶标种群绝对郁闭。 北京地处华北大平原的西北部。北京山地的气候为温带陆地性季风气候,其地带性的落叶阔叶林是以栎林为典型。虽然这些栎林同意大利威尼托刺叶栎林是两种不同的森林类型,但两者之间是存在着一定的联系。其共有的科有20个,共有属有11个。他们在植物组成中,以禾本科,蔷薇科和豆科的植物种类为最多。在乔木层中,他们都是以壳斗科的栎属(Quercus)为优势,其中木犀科的白蜡属(Fraxinus)和槭树属(Acer)较多。 本文对威尼托大区刺叶栎林的物种多度分布格局进行了全面探讨,计算出刺叶栎林的几何分布模型、Broken-stick分布模型、Log分布模型、Log-normat分布模型等四种物种多度分布的理论模型,并将这些理论分布模型用“序列/多度”图解和“多度/频度”图解表示出来。其中,几何分布模型.Broken-stick1分布模型用“序列/多度”图解表示。Broken-stick2分布模型、Log分布模型、Log-normal分布模型用“多度/频度”图解表示。 对上述四个物种多度的理论分布同实际现察的物种多度分布进行X2分析,在5%的显著性水平上,对整个威托大区的刺叶 栎林,几何分布模型最能代表其物种多度分布,显著性最大;Log-normal分布模型也可以用来代表威尼托刺叶标妹的物种多度分布,其显著性次于几何分布模型的显著性。这表明威尼托的刺叶栎林尚处于演替的早期阶段,这些刺叶栎林曾受到严重破坏,现正在恢复。 通过比较Foci del Tagtiamento和Bosco Nordio加尔达湖区、Colli Euganei四个地方刺叶栎林的物种多度的几何分布模型和Log-normal分布模型,显示出Lago di Garda(加尔达湖区)的刺叶栎林生物多样性最好、Foci del Tagtiamento刺叶栎林生物多样性较好.Bosco Nordio的剌叶栎林生物多样性较差.Colli Euganei的刺叶栎林生物多样性最差。 再利用多样性指数计算全部威尼托大区剌叶栎林的生物多样性。计算的多样性指数有丰富度指数(包括Margalef指数、Men-hinick指数、Monk指数)、多样性指数(Shannon信息指数、Bri llouin个息指数、Gini指数、PIE指数、Mcintosh指数)、优势度指数(Berger-Parker指数、Simpson指数)、均一度指数(Pielou均一度指数、Brillouin均一度指数,PIE的V’均一度指数.PIE的V均一度指数,N2的V’均一度指数,N2的V均一度指数,Mclntosh均一度指数,Hill的F10均一度指数,Hill的E21均一度指数,Hill的F21的一度指数)。通过比较丰富度指数,多样性指数、均一度指数与优势度之间的关系,结果,Simpson优势度指数同Men-hinick物种丰富度指数、Shannon信息指数、Bril-louin信息指数、Pielou均一度指数,Brillouin均一度指数,Mcintosh均一度指数、PIE的V’均一度指数呈负相关关系,因此,上述生物多样性指数可以较好地反映威尼托大区刺叶栎林的生物多样性。反映出的结果是:加尔达湖区刺叶栎林生物多样性最好,Foci del Tagtiamento刺叶栎林生物多样性较好,Bosco Nordio的剌叶栎林生物多样性较差.Colli Euganei的刺叶栎林生物多样性最差。 生物多样性的研究显示出生物多样性同生境状况的密切联系。往往受人为干扰严重的群落生物多样性低、如Coli Euganei和亚得里亚海岸刺叶栋林;而受人为破坏较轻的群落其生物多样性高,如加尔达湖区刺叶栎。 生物多样性的研究还显示出生物多样性同群落演替的发展阶段密切相关,在群落演替初期,由于缺乏优势种,而又有大量物种侵入,物多样性相对较高。在群落演替中期,由于形成了一个或几个优势种,优势度的增加导致了生物多样性相对减低。如Foci del Tagtiamento刺叶栎林生物多样性高于Bosco Nordio刺叶栎林的生物多样性。到演替后期,随着更多物种的侵入,群落结构的复杂化、生物多样性又将逐步提高。

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Phylogenetic relationships among 15 species of wood mice (genus Apodemus) were reconstructed to explore some long-standing taxonomic problems. The results provided support for the monophyly of the genus Apodemus, but could not reject the hypothesis of paraphyly for this genus. Our data divided the 15 species into four major groups: (1) the Sylvaemus group (A. sylvaticus, A. flavicollis, A. alpicola, and A. uralensis), (2) the Apodemus group (A. peninsulae, A. chevreri, A. agrarius, A. speciosus, A. draco, A. ilex, A. semotus, A. latronum, and A. mystacinus), (3) A. argenteus, and (4) A. gurkha. Our results also suggested that orestes should be a valid subspecies of A. draco rather than an independent species; in contrast, A. ilex from Yunnan may be regarded as a separate species rather than a synonym of orestes or draco. The species level status of A. latronum, tscherga as synonyms of A. uralensis, and A. chevrieri as a valid species and the closest sibling species of A. agrarius were further corroborated by our data. Applying a molecular clock with the divergences of Mus and Rattus set at 12 million years ago (Mya) as a calibration point, it was estimated that five old lineages (A. mystacinus and four major groups above) diverged in the late Miocene (7.82-12.74 Mya). Then the Apodemus group (excluding A. mystacinus) split into two subgroups: agrarius and draco, at about 7.17-9.95 Mya. Four species of the Sylvaemus group were estimated to diverge at about 2.92-5.21 Mya. The Hengduan Mountains Region was hypothesized to have played important roles in Apodemus evolutionary histories since the Pleistocene. (C) 2004 Elsevier Inc. All rights reserved.

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活性筛选中发现尼泊尔水东哥 (Saurauia napaulensis DC.) 树皮95%乙醇提取物具有α-淀粉酶抑制活性、水麻(Debregeasia orientalis) 枝叶95%乙醇提取物显示血管紧张素转化酶(ACE)抑制活性、青荚叶(Helwingia japonica (Thunb.) Dieter.) 95%乙醇提取物的中小极性部分显示蛋白酪氨酸磷酸酯酶(PTP)1B抑制活性。为全面了解它们的成分及相关活性成份,主要运用硅胶柱层析方法从这三个植物分离得到39个化合物,通过波谱分析或与已知品对照的方法对其进行了鉴定。对木姜冬青(Ilex litseaefolia Hu et Tang)的成分做了进一步的研究,取得了如下结果。 1. 从尼泊尔水东哥树皮的95%乙醇提取物分离并鉴定12个化合物: auranamide、aurantiamide benzoate、齐墩果酸、β-谷甾醇、β-胡萝卜甙、乌苏酸、2α,3α-二羟基-12-烯-28-乌苏酸、2α,3β,24-三羟基-12-烯-28-乌苏酸、(2S,3S,4R,10E)-2-[(2'R)-2' -hydroxytetracosanoylamino] -10-octadecene -1,3,4-triol、 2α,3α,24-三羟基-12-烯-28-齐墩果酸、2α,3β-二羟基-12-烯-28-乌苏酸和2α,3α,24-三羟基-12-烯-28-乌苏酸。 2. 从水麻枝叶的95%乙醇提取物分离并鉴定了18个化合物:棕榈酸、二十烷酸、二十烷酸甲酯、β-谷甾醇、Monogynol A、桦木酸、Hederagenin、β-胡萝卜甙、18αH-19(29)-烯-3-酮-乌苏烷、3,4-开环-20(30)-烯-乌苏烷-3-酸、Pomolic acid,表儿茶素、儿茶素、槲皮素、槲皮素-3-O-β-D-吡喃葡萄糖苷、紫丁香苷、紫丁香酚苷和山萘酚-3-O-芸香糖。儿茶素、槲皮素和槲皮素-3-O-β-D-吡喃葡萄糖苷为具有ACE抑制活性的成分。 3. 从木姜冬青95%乙醇提取物的乙酸乙酯部分分离并鉴定了5个化合物: 2-O-β-D-吡喃葡萄糖-6,2´-二羟基-4,4´-二香草酰氧甲基-1,1´-二苯醚(冬青苷)和四个已知化合物:七叶内酯、香草酸、3,4-二甲氧基苯乙酸和vanilloylcalleryanin。冬青苷为新化合物。 4. 从青荚叶95%乙醇提取物的中小极性部分分离并鉴定了9个化合物:β-谷甾醇、β-胡萝卜苷、羽扇豆醇、桦木醇、桦木酸、棕榈酸甘油酯、桂皮酸、6αH-4-烯-3-酮-豆甾醇和6βH-4-烯-3-酮-豆甾醇。 5. 对1985-2006年间天然二苯醚类化合物及活性研究进展进行综述. The in vitro test indicated that the 95% ethanolic extract of the barks of Saurauia napaulensis DC showed α-amylase inhibitory activity, the 95% ethanolic extract of the whole plants of Debregeasia. orientalis showed angiotensin converting enzyme (ACE) inhibitory activity and some fractions of the 95% ethanolic extract of the aerial parts of Helwingia japonica showed protein tyrosine phosphatase (PTP)1B inhibitory activity. In order to investigate components and active compounds of the three plants, they were chemically studied mainly using. Thirty-nine compounds were isolated predominantly by column chromatography identified by spectral methods or comparing them with authentic samples. Further investigation of Ilex litseaefolia Hu et Tang was carried out. Major results are as follows: 1. Twelve compounds were isolation from the 95% ethanolic extract of the barks of S. napaulensis DC. They were identified as auranamide, aurantiamide benzoate, oleanolic acid, β-sitosterol, β-daucosterol, ursolic acid, 2α,3α-dihydroxyurs-12-en-28-oic acid, 2α,3β,24-trihydroxyurs-12-en-28-oic acid, (2S,3S,4R,10E)-2-[(2'R)-2'-hydroxytetracosanoyl amino]-10-octadecene-1,3,4-triol, 2α,3α,24 -trihydroxyolean-12-en-28-oic acid, 2α,3β-dihydroxyurs-12-en-28-oic acid, and 2α,3α,24-trihydroxyurs-12-ene-28-oic acid, respectively, by spectral methods or comparing them with authentic samples. 2. Eighteen compounds were isolation from the 95% ethanolic extract of the whole plants of D. orientalis. They were identified as palmitic acid, henicosanoic acid, henicosanoic acid methyl ester, β-sitosterol, monogynol, betulinic acid, hederagenin, β-daucosterol, 18αH-urs-20(30)-en-3-one, 3,4-seco-urs-20(30)-en-3-oic acid, pomolic acid, (-)-epicatechin, (+)-catechin, quercetin, quercetin 3-O-β-D-glucopyranoside, syringin, syringiaresinol digloside and kaempferol-3-O-rutinose. (+)-Catechin, quercetin and quercetin 3-O-β-D-glucopyranoside were the ACE inhibitory active components. 3. Further phytochemical investigation of the ethyl acetate parts of 95% ethanolic extract of the whole plant of I. litseaefolia afforded 2-O-β-D-glucopyranose-4,4´-di-vanilloyloxymethyl-2,6´-dihydroxy-1,1´-diphenyl ether (ilexiside), esculetin, vanillic acid, 3,4-dimethoxybenzylacetic acid and vanilloylcalleryanin. Ilexiside was new compound. 4. Nine compounds were isolation from the 95% ethanolic extract of the whole plant of H. japonica: β-sitosterol, β-daucosterol, lupeol, betulin, betulinic acid, glycerol monopalmitate, cinnamic acid, stignast-4-en-6β-3-one and stignast-4-en-6α-3-one 5.Diphenyl ether compounds from nature between 1985-2006 were summarized.