929 resultados para Taxonomia vegetal : Orchidaceae
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兰科(Orchidaceae)是高等植物中第二大科,包括石斛属在内的许多种类均具有较高的观赏价值和独特的药用价值。过度采挖和商业利用及原生境丧失致使野生兰科植物资源受到了毁灭性的破坏,许多兰科植物种类日趋濒危。本研究以海南岛野生兰科植物为对象,从生物多样性、群落生态学、菌根体系的建立和重引入实施工程等方面开展工作,研究结果如下: 1)报道了中国兰科植物2个新种,1个中国新记录属,6个中国新记录种及11个海南新记录种。其中,2个新种为长筒天麻Gastrodia longitubularis和芳香白点兰Thrixspermum odoratum;1个中国新记录属为小囊兰属Micropera;6个中国新记录种,分别为疏花羊耳蒜Liparis sparsiflora、三色槌柱兰Malleola insectifera.、红花小囊兰Micropera poilanei、美丽云叶兰Nephelaphyllum pulchrum、腐生齿唇兰Odontochilus saprophyticu和白花曲唇兰Panisea albiflora;11个海南新记录种,分别为密花石豆兰Bulbophyllum odoratissimum、金唇兰Chrysoglossum ornatum、勐海隔距兰Cleisostoma menghaiense、束花石斛Dendrobium chrysanthum、无叶美冠兰Eulophia zollingeri、滇南翻唇兰Hetaeria rubens、心叶球柄兰Mischobulbum cordifolium、毛叶芋兰Nerviliaplicata、平卧曲唇兰Panisea cavalerei、云南曲唇兰Panisea yunnanensisi及台湾白点兰Thrixspermum formosanum。 2)海南琼北火山岩地区调查结果表明,该区有兰科植物10属14种,成斑块状分布;其区系成分单一,生活型不全面;附主植物种类多样,人工种植的经济作物为该地区兰科植物的主要附生宿主。生境特征分析结果显示,琼北火山岩地区独特的地质气候条件及植被类型是影响该地区兰科植物种类数量的主要因素。人工干扰所致的植被破坏、生境破碎化是该地区兰科植物多样性丧失的主导因素。 3)以我国兰科海南特有种-华石斛(Dendrobium sinense TangetWang)为研究对象,采用双向指示种分析法(TWINSPAN)和除趋势对应分析法(DCA)对海南霸王岭国家级自然保护区华石斛附生群落进行了分类和排序。结果表明:TWINSPAN分类结果将22个样方划分为2个植被类型、5个群系、7个群丛组;并分别对各群丛组的生境特点、植被树种组成作了论述。DCA二维排序图较好地验证了TWINSPAN的分类结果,并客观地反映了群落的生境特征。随着海拔逐渐升高,华石斛附生群落植被类型从山地常绿林逐渐过渡到高山苔藓矮林,群落中的优势种由喜高温耐干旱的热带、亚热带树种逐渐演变为耐低温喜湿的亚热带、温带树种。华石斛在主要群落类型群系间、群丛组内的数量、密度和空间分布格局表现出较大差异,以具通风、凉爽和高湿环境的高山苔藓矮林附生数量最多。附生群落类型的多样性反映了华石斛对多样生境的适应性。华石斛附生群落植被类型群丛组的划分,进一步细化和丰富了海南热带森林植被类型山地常绿林和高山矮林的划分,有助于了解华石斛自然居群的生境特点,为进一步开展华石斛的保育工作提供了科学依据。 4)兰科菌根菌对兰花种子萌发和原球茎生长起了重要作用,在成年阶段也扮演着重要角色。为了解东南亚特有种五唇兰的菌根形态和菌根真菌的动态侵染过程,对不同生境下两种变异类型(叶背绿色和叶背紫色)的成年植株菌根分三个时间段采样并进行显微观察。结果表明,成年的五唇兰植株与菌根真菌有着密切关系,菌丝的侵染、定殖和消解程度随着生长发育变化而变化;在营养生长阶段和生殖生长阶段都发现菌丝结,这两个阶段的菌丝特征有所不同;而在休眠阶段的菌根中观察不到菌丝结;不同生境和不同变异类型的菌根结构无明显区别。 5)利用种子原地共生萌发技术,通过种子预处理及播种等技术的不断完善,获得了大量种子萌发原球茎;初步揭示了华石斛种子萌发原球茎规律。结果表明:10%NaOH浸泡10min预处理能显著提高华石斛种子萌发率;原生境人工播种明显提高了萌发的原球茎数及宿主原球茎产生率;但不同附生宿主间存在差异,自然萌发原球茎数非常低。播种后2.5个月左右种子开始萌发,4.5个月左右达到高峰,在6.5个月原球茎数基本趋于稳定。 6)华石斛菌根化苗重引入实验结果表明,实验室筛选的有益真菌与原生境下筛选有益真菌存在一定差异。菌根化苗重引入野外生境,3个月后以12号华石斛菌根化苗生长最好,3、9号华石斛菌根化苗生长较正常,而7、10号两种华石斛菌根化苗叶片受损或死亡,无菌组培苗基本已死亡;华石斛菌根化苗成活率在50%以上,而对照几乎全部死亡;从菌根化苗长势评价,3、9、12号3个内生真菌华石斛菌根化苗生长较好,为真正有益共生真菌。
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To investigate germline development and germ cell specification, we identified a Dazl homolog (CagDazl) from gynogenetic gibel carp (Carassius auratus gibelio). Its cDNA sequence and BAC clone sequence analyses revealed the genomic organization conservation and conserved synteny of the Dazl family members and their neighborhood genes among vertebrates, especially in fish. Moreover, a polyclonal antibody specific to CagDazl was produced and used to examine its expression and distribution throughout germline development at protein level. Firstly, ovary-specific expression pattern of CagDazl was confirmed in adult tissues by RT-PCR and Western blot. In addition, in situ hybridization and immunofluorescence localization demonstrated its specific expression in germ cells, and both its transcript and protein were localized to germ plasm. Then, co-localization of CagDazl and mitochondrial cloud was found, confirming that CagDazl transcript and its protein are germ plasm component and move via METRO pathway during oogenesis. Furthermore, the CagDazl is abundant and continuous throughout germline development and germ cell specification including primordial germ cell (PGC) formation, oogonium differentiation, oocyte development, and embryogenesis, and the dynamic distribution occurs at different development stages. The data suggest that maternal CagDazl might play an important role in gibel carp PGC formation. Therefore, CagDazl is a useful and specific marker for tracing germ plasm and germ cell development in the gynogenetic gibel carp. In addition, in comparison with previous studies in sexual reproduction species, the continuous and dynamic distribution of CagDazl protein in the germ plasm throughout the life cycle seems to have significant implication in sex evolution of vertebrates. J. Exp. Zool. (Mol. Deu. Euol.) 312B:855-871, 2009. (C) 2009 Wiley-Liss, Inc.
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通过大田玉米试验,验证新型土壤改良剂对夏玉米生育期土壤水分、紧实度及玉米生理生长特性的影响。结果表明,施用改良剂PJG和PFL夏玉米全生育期平均株高、叶面积分别高于对照20.7%、19.75%和51.88%、72.37%;2种改良剂对干物质积累的影响存在差异,影响效果依次为茎干重>叶干重>根干重。夏玉米光合速率和叶绿素含量受土壤改良剂影响较大,PJG和PFL分别高于对照29.96%、24.48%和73.36%、68.53%。在0~10 cm土层内,施用PJG和PFL后土壤紧实度分别低于对照44.44%和42.91%。施用改良剂PJG后,0~20 cm土层土壤含水量维持在田间持水量的77.9%左右,未施用改良剂土壤,夏玉米生育期表层土壤含水量起伏变化较大。土壤改良剂PJG在夏玉米的施用效果略好于PFL。
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水土流失是一个全球性的环境问题 ,给人类的生命和物质财产造成极大的危害与破坏。在现代社会 ,由于人口的持续增长、社会经济生产规模的不断扩大、植被破坏的急剧发展 ,对国家经济的发展构成了威胁。在上述背景下 ,本文在对以往研究结果进行综合分析的基础上 ,根据“再造一个山川秀美的西北地区”之要求 ,因地制宜地提出了我国水土流失的防治途径。
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Amphioxus Bblhx3 was identified as a LIM-homeobox gene expressed in gastrulae. Structural analysis suggested that it is a member of lhx3 but not of lhx1 gene group. Whole mount in situ hybridization revealed, that expression of Bblhx3 was initiated at the early gastrula stage and continued at least until 10-day larvae. Expression of Bblhx3 first appeared in the vegetal and future dorsal area in initial gastrulae and became restricted to the endoderm during gastrulation. In neurulae and early larvae, Bblhx3 was expressed in the developing neural tube, the notochord and preoral pit lineage. In 10-day larvae, Bblhx3 was expressed only in the preoral pit. This expression pattern is apparently distinct from that of vertebrate lhx3 genes that are not expressed during gastrulation. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.
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In amphioxus embryos, the nascent and early mesoderm (including chorda-mesoderm) was visualized by expression of a Brachyury gene (AmBra-2). A band of mesoderm is first detected encircling the earliest (vegetal plate stage) gastrula sub-equatorially. Soon thereafter, the vegetal plate invaginates. resulting in a cap-shaped gastrula with the mesoderm localized at the blastoporal lip and completely encircling the blastopore. As the gastrula stage progresses, DiI (a vital dye) labeling demonstrates that the entire mesoderm is internalized by a slight involution of the epiblast into the hypoblast all around the perimeter of the blastopore. Subsequently. during the early neurula stage, the internalized mesoderm undergoes anterior extension mid-dorsally (as notochord) and dorsolaterally (in paraxial regions when segments will later form). By the late neurula stage, AmBra-2 is no longer transcribed throughout the mesoderm as a whole; instead. expression is detectable only in the posterior mesoderm and in the notochord, but not in par axial mesoderm where definitive somites have formed.
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Fully grown oocytes of Apostichopus japonicus have a cytoplasmic protuberance where the oocyte attaches to the follicle. The protuberance and the oolamina located on the opposite side of the oocyte indicate the animal-vegetal axis. Two pre-meiotic centrosomes are anchored to the protuberance by microtubules between centrosomes and protuberance. After meiosis reinitiation induced by DTT solution, the germinal vesicle (GV) migrates towards the protuberance. The GV breaks down after it migrates to the oocyte membrane on the protuberance side. The protuberance then contracts back into the oocyte and the first polar body extrudes from the site of the former protuberance. The second polar body forms beneath the first. Thus the oocyte protuberance indicates the presumptive animal pole well before maturation of the oocyte.
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The lithology of the buried hill of Triassic Budate group in Beier depression is epimetamorphic clastic rock and volcanic clastic rock stratum. Recently the favorable hydrocarbon show was discovered in buried hill of base rock, and large-duty industrial oil stream was obtained in some wells in Beier depression. Based on the information of seismos and wells, the tectonic framework, tectonic deformation times and faulted system of the Beier depression are comprehensively studied, then configuration, evolutional history, genetic type and distributed regularity of buried hill are defined. According to observing description and analysis of core sample, well logging and interpretive result of FMI, the lithological component, diagenetic type and diagenetic sequence of buried hill reservoir are confirmed, then reservoir space system of buried hill is distinguished, and vegetal feature, genetic mechanism and distributed regularity of buried hill fissure are researched, at the same time the quantitative relationship is build up between core fissures and fissures interpreted by FMI. After that fundamental supervisory action of fault is defined to the vegetal degree of fissure, and the fissure beneficial places are forecasted using fractal theory and approach. At last the beneficial areas of Budate group reservoir are forecasted by reservoir appraisal parameters optimization such as multivariate gradually regression analysis et. al. and reservoir comprehensive appraisal method such as weighing analyze and clustering procedure et. al. which can provide foundation for the next exploratory disposition. Such production and knowledge are obtained in this text as those: 1. Four structural layers and two faulting systems are developed, and four structural layers are carved up by three bed succession boundary surfaces which creates three tectonic distortional times homology. Three types of buried hill are divided, they are ancient physiognomy buried hill, epigenetic buried hill, and contemporaneous buried hill. 2. Reservoir space of Budate buried hill is mainly secondary pore space and fissure, which distributes near the unconformity and/or inside buried hill in sections. The buried hill reservoir experienced multi-type and multi-stage diagenetic reconstruction, which led to the original porosity disappeared, and multi secondary porosity was created by dissolution, superficial clastation and cataclasis et. al. in diagenetic stage, which including middle crystal pore, inter crystal pore, moldic pore, inter particle emposieu, corrosion pore space and fissure et. al. which improved distinctly reservoir capability of buried hill. 3. The inner reservoir of buried hill in Beier depression is not stratigraphic bedded construction, but is fissure developing place formed by inner fault and broken lithogenetic belt. The fissures in inner reservoir of buried hill are developed unequally with many fissure types, which mainly are high angle fissure and dictyonal fissures and its developing degree and distribution is chiefly controlled by faulting. 4. The results of reservoir comprehensive evaluate and reservoir predicting indicates that advantageous areas of reservoir of buried hill chiefly distributes in Sudeerte, Beixi and Huoduomoer, which comprehensive evaluate mainly Ⅱand Ⅲ type reservoir. The clues and results of this text have directive significance for understanding the hydrocarbon reservoir condition of buried hill in Beier depression, for studying hydrocarbon accumulated mechanism and distributed regularity, and for guiding oil and gas exploration. The results of this text also can enrich and improve nonmarine hydrocarbon accumulated theory.
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2008
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2008
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2008
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A bracatinga é uma espécie nativa e, há mais de 100 anos, tem seu uso norteado pelo mercado de lenha para queima direta, seja em locomotivas de ferro, em residências ou em indústrias regionais. Atualmente, a demanda por madeira de bracatinga está voltada para atender parte das necessidades relativas de madeira para energia assim como para outras finalidades industriais, tais como: serraria, laminação, movelaria e placas e painéis. As áreas com bracatinga ultrapassam os 120 mil hectares, concentrando-se em pouco mais de 60 municípios paranaenses, em escala comercial, envolvendo mais de 15.000 pequenas propriedades rurais (média de 250 famílias por município). Formam um eixo principal de produção desde o Alto Vale da Ribeira até União da Vitória. O quadro agrário da Região Metropolitana de Curitiba, em especial na área norte, é caracterizado pela estagnação socioeconômica do meio rural, em decorrência do: * Rigor unilateral na aplicação da legislação ambiental, especialmente pelo IAP. * Êxodo rural decorrente da inviabilidade econômica das pequenas propriedades rurais, com padrão de Agricultura Familiar. * Predomínio de solos com topografia acidentada e baixa fertilidade natural. * Poucas alternativas para o desenvolvimento socioeconômico regional.
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Estado da arte; Recursos genéticos; Estratégias de melhoramento; Desenvolvimento experimental.
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Métodos para GWS; Teoria dos métodos de regressão; Computação do método Random (Ridge) Regression BLUP (RR-BLUP/GWS); Fenótipos corrigidos; Frequências alélicas, variância dos marcadores e herdabilidade; Marcadores codominantes (SNP) ? Modelo genotípico; Marcadores dominantes (DArT) - Modelo genotípico; Marcadores codominantes (SNP) ? Modelo gamético ou alélico; Número de marcadores com efeitos significativos; Populações de estimação, validação e seleção; População de validação e Jacknife; Correlação e regressão entre valores genéticos preditos e fenótipos na população de validação; Análise de associação na GWAS; Software Selegen Genômica: Random (Ridge) Regression BLUP: RR-BLUP/GWS; Exemplo aplicado ao melhoramento do eucalipto.
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2002