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1.
常绿杜鹃亚属Subgenus Hymenanthes是由K.Koch(1872)根据Blume(1826)建立的Genus Hymenanthes改级组合而成。但长期以来人们一直沿用了Maximowicz(1870)所建立的、后由Koehne(1893)修订过的Subgenus Eurhododendron这一亚属名称,直到最近D.F.Chamberlain(1978,1979,1982)对该亚属的名称才作了正式订正。  相似文献   

2.
为探明常绿杜鹃亚属植物高温致伤的生理机制,以猴头杜鹃(Rhododendron simiarum Hance)、井冈山杜鹃(R.jinggangshanicumTam)四年生实生苗为材料,通过人工气候箱中的盆栽实验,研究了不同程度的高温胁迫对两种常绿亚属杜鹃幼苗叶片生理生化特性的影响。结果表明:(1)两种杜鹃叶片的丙二醛(MDA)、过氧化氢(H2O2)及脯氨酸(Pro)、可溶性蛋白质含量均随胁迫温度的升高而增大;猴头杜鹃的H2O2、可溶性蛋白含量及增幅均明显小于井冈山杜鹃,而MDA、Pro的增幅则因胁迫温度而异。(2)两种杜鹃叶片抗坏血酸(AsA)含量均随胁迫温度的升高而降低,但猴头杜鹃的降幅小于井冈山杜鹃。(3)高温胁迫下,猴头杜鹃除过氧化氢酶(CAT)活性增幅略小外,超氧化物歧化酶(SOD)、过氧化物酶(POD)及抗坏血酸过氧化物酶(APX)增幅均大于井冈山杜鹃。可见,随着胁迫温度的升高两种杜鹃叶片膜脂过氧化作用加重,而猴头杜鹃较井冈山杜鹃具有更强的酶促和非酶促清除活性氧能力。  相似文献   

3.
不同因子对常绿杜鹃亚属种子萌发及成苗的影响   总被引:4,自引:0,他引:4  
杜鹃属常绿杜鹃亚属多分布于中国西南高海拔地区,播种育苗为其有效的引种手段。试验表明:(1)环境温度、物种系统位置对萌发速度影响较大,平均气温20℃以下,温度越高萌发越快;材料较多的4个亚组以云锦杜鹃亚组萌发最快,银叶杜鹃亚组、露珠杜鹃亚组居中,长序杜鹃亚组最慢。(2)出苗、成苗率及幼苗生长与播种基质、物种产地、来源、系统位置等密切相关,出苗率以“腐殖土”基质为高,而成苗率及幼苗生长以“腐殖土 苔藓”基质为好;原产华东、华南、华中的种育苗效果总体优于西南种,日本、北美种好于欧洲种;经过驯化的种好于采自原产地的种,3个主要种源地育苗表现为:以本园的种子最佳、云南次之、德国最差;向东部演化的种育苗效果好于向西南演化的种。(3)庐山冷凉湿润的气候较适宜于本亚属杜鹃的播种育苗,苗期管理及猝倒病防治是其育苗成败关键。  相似文献   

4.
23种常绿杜鹃亚属植物种间杂交的可育性研究   总被引:1,自引:0,他引:1  
庄平 《广西植物》2018,38(12):1545-1557
该文对常绿杜鹃亚属(subgen. Hymenanthes)的12个亚组23种杜鹃花的64个杂交组合进行了研究,包括云锦杜鹃亚组(subsect. Fortunea)、银叶杜鹃亚组(subsect. Argyrophylla)及同亚属的其他10个亚组[杯毛杜鹃亚组(subsect. Falconera)、弯果杜鹃亚组(subsec. Campylocarpa)、麻花杜鹃亚组(subsect. Maculifera)、粘毛杜鹃亚组(subsect. Glischra)、露珠杜鹃亚组(subsect. Irrorata)、大理杜鹃亚组(subsect. Taliensia)、树形杜鹃亚组(subsect. Arborea)、蜜腺杜鹃亚组(subsect. Thomsonia)、星毛杜鹃亚组(subsect. Parishia)、火红杜鹃亚组(subsect. Neriiflora)]。结果表明:(1)常绿杜鹃亚属内的异种杂交具有很高的可育性,在64个杂交组合中可育与高可育组合56个(占87.5%),无弱可育等级。(2)不亲和与败育组合8个,不能坐果(Cab)、不能结实(Sab)和结实不发芽(Sng)之比为3∶1∶4,并与杂交双亲的亲缘有一定关联,初步推断同时存在前合子期不亲和(pre-zygotic incompatibility)与后合子期败育(post-zygotic abortion)的情形。(3)与相应的自然授粉比较,常绿杜鹃亚属内杂交会不同程度地导致可育性降低,但有15个组内与组间杂交组合表现了某种"超亲和"现象,尽管不能完全排除人工杂交对于结实与可育性的加强作用。(4)常绿杜鹃亚属内不同种类间杂交,存在双向可育与单向不育(unilateral sterility)现象,但未见双向不育情况。  相似文献   

5.
四川常绿杜鹃亚属一新种   总被引:5,自引:0,他引:5  
四川常绿杜鹃亚属一新种何明友,胡琳贞,张家藻,刘绍龙,李文荣,朱荃,李勇(四川联合大学生物系,成都610064)(四川省地震局,成都610064)关键词杜鹃花属,黑竹沟杜鹃,新分类群ANEWSPECIESOFSUBGENUSHYMENANTHESFR...  相似文献   

6.
以杜鹃花属(Rhododendron L.)5个亚属5种杜鹃的4年生实生苗为材料,对模拟高温(30℃和38℃)条件下叶片丙二醛(MDA)、过氧化氢(H2O2)和脯氨酸(Pro)含量以及超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性进行了测定分析,对各指标进行了相关性和主成分分析;在此基础上,采用隶属函数法对5种杜鹃的耐热性进行了综合评价,并通过建立最优回归方程对综合评价结果进行检验.测定结果表明:与对照( 22℃)相比,5种杜鹃幼苗的MDA、H2O2和Pro含量以及CAT和APX活性均随胁迫温度的升高而增加;SOD活性则表现为在30℃条件下小幅增加、38℃条件下下降的趋势.CAT活性与H2O2和Pro含量及APX活性均呈极显著正相关关系(P<0.01),APX活性与Pro含量和SOD活性分别呈显著的正相关和负相关关系(P<0.05).通过主成分分析可将测定的6个单项指标转换成3个相互独立的综合指标,累计贡献率达87.52%.根据综合评价值(D),可将5种杜鹃的耐热性分为4个等级:白花杜鹃[R.mucronatum (Blume)G.Don]的耐热性最强,毛棉杜鹃(R.moulmainense Hook.f.)和羊踯躅[R.molle (Blume)G.Don]耐热性较强,红滩杜鹃(R.chihsinanum Chun et Fang)耐热性较弱,红棕杜鹃(R.rubiginosum Franch.)的耐热性最弱.利用所建立的最优同归方程对供试种类进行耐热性预测,预测值与D值的次序完全一致,表明综合评价法可用于杜鹃苗期耐热性的评价.  相似文献   

7.
首次报道了杜鹃属马银花亚属四组20种2变种植物的花粉形态。本亚属植物的花粉均为四合花粉,呈正四面体排列,四合体直径为35.85-60.72μm。单粒花粉球形或近球形,具三孔沟。在四合花粉上,相邻花粉粒上的沟相连花粉粒表面或多或少具粘丝。在扫描电镜下,花粉粒呈现出粗糙、不明显聚颗粒状至致密的聚颗粒状等不同的纹饰,在不同的组间存在或多或少的差异,具有一定的分类学意义。对某些种的分类处理也能够提供某些孢粉学证据。  相似文献   

8.
杜鹃属马银花亚属花粉形态的研究   总被引:14,自引:2,他引:14  
首次报道了杜鹃属马银花亚属四组 2 0种 2变种植物的花粉形态。本亚属植物的花粉均为四合花粉 ,呈正四面体排列 ,四合体直径为 35 .85~ 6 0 .72 μm。单粒花粉球形或近球形 ,具三孔沟。在四合花粉上 ,相邻花粉粒上的沟相连 ,花粉粒表面或多或少具粘丝。在扫描电镜下 ,花粉粒呈现出粗糙、不明显聚颗粒状至致密的聚颗粒状等不同的纹饰 ,在不同的组间存在或多或少的差异 ,具有一定的分类学意义。对某些种的分类处理也能够提供某些孢粉学证据。  相似文献   

9.
基于ITS序列分析探讨杜鹃属映山红亚属的组间关系   总被引:15,自引:0,他引:15  
以叶状苞亚属的叶状苞杜鹃为外类群,以杜鹃属映山红亚属(subg.Tsutsusi)2组12种杜鹃和羊踯躅亚属(subg.Pentanthera)3种4种杜鹃的ITS区(包括5.8S rDNA)的序列了系统学分析。3个亚属的ITS区序长度范围为642-645bp。排序后ITS区的序列长度为653个位点,gap做缺失处理时,变异位点和信息位点分别占6.58%和3.68%。运用PAUP4.0软件分析,获得15个最简树,步长为75,一致性指数(CI)和维持性指数(RI)值分别为0.9333和0.9515,利用15个最简约树获取严格一致树,结果表明:1)映山红亚属为一单系类群,其内部支持率为81%;2)不支持将R.ashiroi独立成假映山红组,也不支持将R.tashiroi并入映山红组,而支持将R.tashiroi并入轮生叶组中的观点;3)支持将R.tsusiophyllum并入映山红组中的观点;4)大字杜鹃的系统位置还需进一步的研究。  相似文献   

10.
庄平 《广西植物》2018,38(12):1558-1565
为探索杜鹃花亚属内异种杂交的可育性及其规律,对杜鹃亚属有鳞大花亚组(subsect. Maddenia)、三花杜鹃亚组(subsect. Triflora)、亮鳞杜鹃亚组(subsect. Heliolepida)及腋花杜鹃亚组(subsect. Scabrifolia)等4亚组10个杜鹃花种类的22个杂交组合(其中18个数据完整组合)的可育性进行了研究。结果表明:(1)所涉及的杜鹃亚属不同亚组间及三花杜鹃亚组内杂交均较困难,在18个数据完整组合中高可育与可育组合比率明显偏低,不育比率高(55.6%)。(2)在10个不可育或败育组合中,不能坐果(Cab型)、不能结实(Sab型)和可结实而种子不能发芽(Sng型)的数量分布为6∶1∶3,其不亲和或败育发生的阶段可能涵盖了从前合子期到后合子期的整个阶段。(3)亲本一方为多倍体组合的可育率(41.6%),尤其是母本为多倍体时,比二倍体组合的可育率(50.0%)低且无高可育组合出现,部分印证了倍性是导致该亚属植物不同种类杂交不亲和、不育与育性下降的重要原因,但不是唯一原因,亚组间杂交的可育率(16.7%)明显低于亚组内(三花杜鹃亚组内,58.3%)。(4)与相应的母本自然授粉结果相比,杂交明显导致多数可育组合绿苗率比率和单位可育种子数量比率的大幅度下降,这是双亲遗传差异及多倍体亲本介入后所导致的杂交衰退hybrid weakness现象。(5)在多倍体作母本的情况下,杂交单向不育或非对称遗传渗透现象明显。  相似文献   

11.
采用国际上使用的"统一特定描述"和"齿体定位描述"方法对寄生在瓦氏黄颡鱼(Peleteobagrusvachelli)鳃上的适度车轮虫(Trichodina modesta)和马氏车轮虫(T.mastu)2种车轮虫的虫体外形、附着盘、齿体、辐线、中央颗粒、核器、口围绕体等形态特征进行了较为详细的描述,并分别与已报道的其他适度车轮虫、马氏车轮虫种群及相似种的形态特征进行了比较。实验证实了瓦氏黄颡鱼为适度车轮虫的寄主新纪录。  相似文献   

12.
13.
In this paper we have attempted to clarify the taxonomy and nomenclature of thirteen taxa of the genus Cortinarius subgenus Telamonia (sections Hydrocybe, Fraternii) well represented in the southwestern Mediterranean area of Europe (C. atrocoeruleus, C. bombycinus, C casimiri, C. contrarius, C. decipiens, C. fraternus, C. gallurae, C. hoffmannii, C. petroselineus, C. sertipes, C. subturibulosus, C. urdaibaiensis and C. vernus). To this end we have performed a combined study of morphological and molecular data (rDNA ITS sequences). The morphological analysis was carried out on 114 collections and the molecular analysis involved 31 of the 114 collections, including 11 type collections (types for C. casimiri and C. fraternus were not available). In addition, a study of spores under field emission scanning electron microscopy (FESEM) was conducted. The results of the combined analysis allowed us to asign the studied material to five species (C. casimiri s.l., C. decipiens s.l., C. gallurae, C. subturibulosus s.l. and C. vernus s.l.). Thus, all collections from more continental areas, which were originally identified as six different taxa (C. atrocoeruleus, C. contrarius, C. decipiens, C. fraternus, C. sertipes, C. flexipes fo. sertipes) corresponded to C. decipiens sensu lato, a widely distributed, genetically and morphologically variable species. Cortinarius casimiri is also found in such habitats, but it is confirmed as distinct taxon. Collections from Mediterranean sclerophyllous communities correspond to C. gallurae, C. vernus sensu lato and C. subturibulosus sensu lato. Due to close phylogenetic relationships we propose the new combinations C. casimiri var. hoffmannii (=C. decipiens var. hoffmannii non C. hoffmannii) and C. subturibulosus var. bombycinus (=C. bombycinus), and the new variety C. vernus var. nevadavernus (=C. vernus H. Lindstr. & Melot sensu auct.).  相似文献   

14.
用具有化感作用或潜在抑草活性的12种植物的叶片水浸液对白花鬼针草(Bidens alba)幼苗进行处理,对其幼苗的生长 进行研究,以期筛选出对白花鬼针草生长有较强抑制作用的植物种类。结果表明,12种供体植物叶片水浸液(0.05 g DW mL-1) 均能显著抑制白花鬼针草幼苗的生长(P<0.05),综合化感效应(SE)均为负值(≤-0.2),抑制强度依次为假臭草(Eupatorium catarium)>胜红蓟(Ageratum conyzoides)>海芋(Alocasia macrorrhiza)>水茄(Solanum torvum)>马缨丹(Lantana camara)>薇甘菊(Mikania micrantha)>构树(Broussonetia papyrifera)>南美蟛蜞菊(Wedelia trilobata)>三裂叶薯(Ipomoea triloba)>葛藤(Pueraria lobata)>鸡矢藤(Paederia scandens)>五爪金龙(Ipomoea cairica),其中假臭草叶水浸液浓度仅为0.04 g DW mL-1时就可以使白花鬼针草死亡。假臭草和胜红蓟的茎水浸液也可以显著抑制白花鬼针草的生长(P<0.05),抑制效果略低于叶水浸液。回归分析表明,假臭草叶水浸液浓度与白花鬼针草的生物量等指标之间有线性回归关系(R2>0.85, P<0.001),随着水浸液浓度的增加,白花鬼针草的生物量等指标下降。防除白花鬼针草时使用假臭草和胜红蓟的茎、叶水浸液, 其有效浓度低且资源丰富,可作为白花鬼针草天然除草剂的主要资源植物。  相似文献   

15.
为了解水稻(Oryza sativa)响应重金属污染及对重金属积累的机制,利用生物信息学手段对水稻金属耐受蛋白(metal tolerance protein, MTP) OsMTP2的结构特征进行预测,并分析OsMTP2基因的表达特征。结果表明,该蛋白由415个氨基酸组成,具有很强的疏水性。mRNA原位杂交结果表明,OsMTP2在叶片输导组织中有较强的表达,但在根、花药中没有检测到明显的杂交信号。这说明水稻金属耐受蛋白基因OsMTP2主要在输导组织中表达,并在金属离子运输中发挥重要作用。  相似文献   

16.
The ultrastructure of septa and septum-associated septal pore caps are important taxonomic markers in the Agaricomycotina (Basidiomycota, Fungi). The septal pore caps covering the typical basidiomycetous dolipore septum are divided into three main phenotypically recognized morphotypes: vesicular-tubular (including the vesicular, sacculate, tubular, ampulliform, and globular morphotypes), imperforate, and perforate. Until recently, the septal pore cap-type reflected the higher-order relationships within the Agaricomycotina. However, the new classification of Fungi resulted in many changes including revision of existing and addition of new orders. Therefore, the septal pore cap ultrastructure of more than 325 species as reported in literature was related to this new classification. In addition, the septal pore cap ultrastructures of Rickenella fibula and Cantharellus formosus were examined by transmission electron microscopy. Both fungi have dolipore septa associated with perforate septal pore caps. These results combined with data from the literature show that the septal pore cap-type within orders of the Agaricomycotina is generally monomorphic, except for the Cantharellales and Hymenochaetales.It appears from the fungal phylogeny combined with the septal pore cap ultrastructure that the vesicular-tubular and the imperforate type both may have arisen from endoplasmic reticulum. Thereafter, the imperforate type eventually gave rise to the perforate septal pore cap-type.  相似文献   

17.
使用SignalP-4.0软件预测信号肽剪切位点,设计引物扩增建鲤(Cyprinus carpio var.jian)leptin基因(jlLEP-A1,jlLEP-B)不含信号肽的ORF区域。扩增产物分别连接到pET-32a(+)和pGex-4T-1原核表达载体,构建重组质粒,测序验证插入位点的正确性。将重组质粒转化大肠杆菌BL21(DE3),经IPTG诱导表达重组蛋白pET-32a(+)/jlLEP-A1,pET-32a(+)/jlLEP-B和pGex-4T-1/jlLEP-A1,pGex-4T-1/jlLEP-B。结果表明,在37℃和1 mmol/L IPTG的条件下诱导5 h,重组蛋白表达量最大。SDS-PAGE电泳显示重组蛋白主要以可溶蛋白形式存在。这一结果为后续的建鲤leptin基因功能研究奠定了基础。  相似文献   

18.
Promastigotes of Leishmania (Viannia) panamensis were successfully transfected with p6.5-egfp to express green fluorescent protein. The transfectants remained infective to macrophages, providing an in vitro model for screening antileishmanial drugs. This was demonstrated by flow cytometry of macrophage-associated GFP after exposure of infected cultures to known antileishmanial drugs, i.e. amphotericin B and glucantime®. Fluorescence of GFP diminished progressively from infected cells with increasing drug concentrations used in both cases. The availability of this fluorescent assay for infection of macrophages by L. (V.) panamensis facilitates drug discovery program for the Viannia species, which differ significantly from those of the Leishmania subgenus.  相似文献   

19.
Hyaloscyphaceae is the largest family in Helotiales, Leotiomycetes. It is mainly characterized by minute apothecia with well-differentiated hairs, but its taxonomic delimitation and infrafamilial classification remain ambiguous. This study performed molecular phylogenetic analyses using multiple genes including the ITS-5.8S rDNA, the D1–D2 region of large subunit of rDNA, RNA polymerase II subunit 2, and the mitochondrial small subunit. The primary objective was to evaluate the phylogenetic utility of morphological characters traditionally used in the taxonomy of Hyaloscyphaceae through reassessment of the monophyly of this family and its genera. The phylogenetic analyses inferred Hyaloscyphaceae as being a heterogeneous assemblage of a diverse group of fungi and not supported as monophyletic. Among the three tribes of Hyaloscyphaceae only Lachneae formed a monophyletic lineage. The presence of hairs is rejected as a synapomorphy, since morphologically diversified hairs have originated independently during the evolution of Helotiales. The true- and false-subiculum in Arachnopezizeae are hypothesized to have evolved through different evolutionary processes; the true-subiculum is likely the product of a single evolutionary origin, while the false-subiculum is hypothesized to have originated multiple times. Since Hyaloscyphaceae sensu lato was not resolved as monophyletic, Hyaloscyphaceae sensu stricto is redefined and only applied to the genus Hyaloscypha.  相似文献   

20.
Amaranthus retroflexus L. and Chenopodium glaucum L. are two widely distributed destructive weeds. Their strong adaptability and massive seed production make them the hardest weeds to deal with. This present study intended to investigate the effect of leachate from Eupatorium adenophorum on the growth of these weeds and explore the potential to develop an environmental friendly strategy to use the leachate to control the weeds. Seeds of A. retroflexus L. and C. glaucum L. were soaked in solutions containing 0%, 0.6%, 1.25%, 2.5%, and 5% leachate from E. adenophorum leaves. A. retroflexus and C. glaucum seedlings grown in pots were sprayed with leachate solutions in the same concentration range. The effects of these leachate solutions on membrane permeability and germination of seeds, and growth and physiological characteristics of the seedlings were investigated. The highest concentration of leachate (5%) caused significant damage to the cell membrane of seeds of both weed species, whereas lower concentrations (0.6%) promoted repair of the membrane system, as reflected by higher and lower than control in relative conductivity (RC), respectively. Different concentrations of leachate showed distinct allelopathic inhibitory effects on the two weed species; lower concentrations showed weak inhibitory or even positive effects, whereas higher concentrations showed stronger inhibitory effects. Higher concentrations of leachate (2.5% and 5%) delayed germination and significantly decreased the emergence rate of the seeds, survival rate, and dry matter accumulation of the seedlings. When treated by 5% leachate, the emergence date of A. retroflexus was delayed by 3.6 d, emergence rate of the seeds and survival rate was 69.1% and 70.6% of the control, respectively, seedling dry matter was 48.6% less than the control; In the case of C. glaucum, the emergence date was delayed by 2.7 d, emergence rate of the seeds and survival rate was 45.1% and 58.6% of the control, respectively, seedling dry matter was 44.7% less than the control. There were significant interactions among the different concentrations of leachate and the length of treatment period with respect to activities of antioxidant enzymes, malondialdehyde (MDA) contents, and chlorophyll contents. Seedlings treated with 0.6%, 1.25%, or 2.5% leachate solution for 24–72 h showed increased superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities. When seedlings were treated with leachate solutions for 96 h, antioxidant enzyme activities and chlorophyll content decreased in A. retroflexus, but only CAT activity decreased in C. glaucum. When seedlings of the two weed species were treated with 5% leachate solution, CAT activity and chlorophyll content decreased and MDA content gradually increased with longer treatment times (from 24 to 96 h). The two weed species showed different allelopathic responses to E. adenophorum; A. retroflexus was more sensitive than C. glaucum. Based on the investigation, it could be speculated that the delayed germination and low germination rate of the weeds after treatment by leachate could be due to the fact that leachate damaged the membrane system of the seeds. By delaying germination, lowering the germination rate of the weeds and inhibiting seedling growth, leachate from E. adenophorum could provide an effective way of controlling the weeds.  相似文献   

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