基于公共数据库信息对中国野生香菇种质资源地理分布的再分析

本文基于野生香菇资源的文献以及公共数据库中的序列信息,调查了香菇在我国以及世界范围内的地理分布,同时利用ITS序列进行了遗传多样性分析。结果显示香菇在我国的21个省市有分布,其中对云南、四川和湖北等省香菇资源的研究最为密集。不同菌株的聚类与地域来源有一定的相关性,进一步通过多样性分析显示我国野生香菇的多样性中心分布于西北和西南地区。本文有助于指导我们进行香菇野生资源的调查,进一步挖掘香菇种质资源的多样性。     

基于香菇菌株rDNA-ITS序列的系统发育分析

根据真菌核糖体通用引物ITS1和ITS4扩增出13个福建袋栽香菇主要菌株的5.8S rDNA、ITS序列,对该序列进行测序后,得到完整的5.8S rDNA、ITS序列,将该序列提交NCBI并获得登录号,对该序列进行比对分析并构建了系统发育树,从分子水平对香菇菌株进行了区分鉴定,结果显示13个菌株可以明显的分成2丛,而其他菌株又可以从一丛中延伸出几个亚丛。     

中国香菇自然种质遗传多样性的RAPD分析

用RAPD技术分析了收集自中国14个省份、分属于8个不同植物区系的53个野生香菇菌株的DNA多态性.用10个随机引物共扩增出147条DNA带,其中94%具有多态性.供试菌株在RAPD带型及DNA相似性上的差异表明,中国香菇自然群体具有丰富的遗传多样性.其中,横断山脉、云南高原、台湾及华南地区菌株的多样性尤为丰富.用平均连锁聚类法构建了样本的遗传相关聚类图.大多数来自同一区域或相邻区域的菌株优先聚成小类,表明菌株的分组与其地理来源明显相关.以0.66的相似性为切割点,53个菌株可分成4大类群.类群Ⅰ和类群Ⅱ主要由横断山脉、云南高原和华中地区菌株组成,类群Ⅲ包含其他地区的菌株.类群Ⅳ则是由来自华北和四川省的共5个菌株组成的一个小的分支.     

中国香菇自然种质遗传多样性的RAPD分析*

用RAPD技术分析了收集自中国14个省份、分属于8个不同植物区系的53个野生香菇菌株的DNA多态性。用10个随机引物共扩增出147条DNA带,其中94%具有多态性。供试菌株在RAPD带型及DNA相似性上的差异表明,中国香菇自然群体具有丰富的遗传多样性。其中,横断山脉、云南高原、台湾及华南地区菌株的多样性尤为丰富。用平均连锁聚类法构建了样本的遗传相关聚类图。大多数来自同一区域或相邻区域的菌株优先聚成小类,表明菌株的分组与其地理来源明显相关。以0.66的相似性为切割点,53个菌株可分成4大类群。类群Ⅰ和类群Ⅱ主要由横断山脉、云南高原和华中地区菌株组成,类群Ⅲ包含其他地区的菌株。类群Ⅳ则是由来自华北和四川省的共5个菌株组成的一个小的分支。     

中国石蒜属种间亲缘关系ITS序列分析

本文利用核糖体DNA内转录间隔区(ITS)序列对石蒜属13个种(含变种)的亲缘关系进行分析。结果表明,各样品的ITS1长度为259~260 bp,ITS2为230 bp,分别有多个特异性信息位点。以ITS序列为依据对石蒜属植物亲缘关系进行分析,表明石蒜属13个种可分为三大类,其中类Ⅰ包括中国石蒜、地笑、安徽石蒜和长筒石蒜,核型为M+T型;类Ⅱ包括矮小石蒜、换锦花、玫瑰石蒜和红蓝石蒜,核型为ST型;类Ⅲ包括稻草石蒜、乳白石蒜、短蕊石蒜和两种人工杂交种,核型为ST+M+T。系统进化树与核型分析结果相似,第Ⅲ类可能为自然杂交种。     

中国北方马铃薯黑痣病立枯丝核菌的融合群鉴定

从山东、甘肃、青海、内蒙古、河北和黑龙江6省采集马铃薯黑痣病标本300余份,分离获得251个立枯丝核菌Rhizoctonia solani菌株。融合群测定结果表明,这些菌株分别属于多核的丝核菌AG‐3、AG1‐IB、AG4‐HG‐Ⅰ、AG4‐HG‐Ⅱ、AG4‐HG‐Ⅲ、AG‐5和AG‐11融合群。其中AG‐3是优势致病群,占分离菌株总数的71.31%;其次是AG4‐HG‐Ⅰ,占15.14%;AG‐11融合群菌株是国内首次从罹病马铃薯植株上分离得到。从各融合群中选取代表性的菌株进行5.8S rDNA‐ITS区序列分析,结果表明,隶属不同融合群或亚群菌株的5.8S rDNA‐ITS区序列存在较大的差异,而相同融合群(亚群)不同菌株的序列具有较高一致性。     

地中海实蝇幼虫分子鉴定

通过对从秘鲁进口的葡萄中截获实蝇类幼虫进行ITS区和线粒体COⅠ,COⅡ,COⅢ、ND5基因序列的扩增和测序,并与GenBank中对应的序列进行比对,结果表明,截获样品ITS区序列和地中海实蝇Ceratitis capitata(Wiedemann)同源性为95·16%(其中ITS1为99·52%,ITS2为86·2%),线粒体COⅠ,COⅡ,COⅢ,ND5基因序列和地中海实蝇C.capitata同源性为100%,99·9%,99·5%,99·8%;基于COⅠ序列构建的系统发育树中,幼虫样品和地中海实蝇最为接近。根据序列分析和系统发育关系分析的结果,将截获的实蝇类幼虫鉴定为地中海实蝇C.capitata。     

用ITS和ISSR分子标记技术鉴别香菇生产用种

通过选用香菇生产中存在名称争议或者名称相近或者同一名称但长期在不同地区栽培的12株香菇生产菌株,以及用于种水平对比的豹皮香菇Lentinuslepideus和虎皮香菇Lentinustigrinus的4个菌株,共16个菌株作为供试材料,进行ITS和ISSR遗传分析,并用RAPD技术验证试验结果。结果证明,不同种的ITS长度存在差异,再次证明ITS可以有效区别种之间的菌株;在ISSR的菌株水平分析中,香菇种内材料拥有两个共同的条带,与其他两种菌株的带型图谱有着明显差异,其中5对材料的带型图谱极为相近。RAPD验证结果与上述结果相近。由此可见,结合ITS与ISSR技术是可以用作香菇生产菌株鉴别的,这为ITS和ISSR分子标记技术推广应用于香菇生产菌株的快速准确鉴别提供了技术依据。     

木耳属真菌rDNA特异性扩增片段的RFLP研究*

对木耳属8个种25个菌株的ITS和28SrDNA5’端两个区域分别进行了PCR扩增和限制酶切片段长度多态性（RFLP）研究。ITS－RFMP研究结果表明,HaeⅢ可将黑木耳与其它种区分开,MspⅠ可将盾形木耳、角质木耳、琥珀木耳和黑木耳4个种区分开,而供试的HaeⅢ、TaqⅠ、HinfⅠ和MaPⅠ这四种限制酶均不能将皱木耳、大木耳、网脉木耳及毛木耳4个种区分开,表明它们之间的亲缘关系较近;结果还表明,ITS—rDNA拷贝在毛木耳和琥珀木耳种内是异质性的,而在黑木耳种内是同质性的。285rDNA-RFLP研究结果表明,供试的4种限制酶中,仅MspⅠ可将盾形木耳和角质木耳区分开,而不能将其它种区分开,这显示了28SrDNA序列在木耳属不同种间的保守性。     

木耳属真菌rDNA特异性扩增片段的RFLP研究

对木耳属8个种25个菌株的ITS和28SrDNA5’端两个区域分别进行了PCR扩增和限制酶切片段长度多态性（RFLP）研究。ITS－RFMP研究结果表明,HaeⅢ可将黑木耳与其它种区分开,MspⅠ可将盾形木耳、角质木耳、琥珀木耳和黑木耳4个种区分开,而供试的HaeⅢ、TaqⅠ、HinfⅠ和MaPⅠ这四种限制酶均不能将皱木耳、大木耳、网脉木耳及毛木耳4个种区分开,表明它们之间的亲缘关系较近;结果还表明,ITS—rDNA拷贝在毛木耳和琥珀木耳种内是异质性的,而在黑木耳种内是同质性的。285rDNA-RFLP研究结果表明,供试的4种限制酶中,仅MspⅠ可将盾形木耳和角质木耳区分开,而不能将其它种区分开,这显示了28SrDNA序列在木耳属不同种间的保守性。     

Genetic differentiation and cryptic speciation in natural populations of Drosophila lacertosa

Drosophila lacertosa, an Oriental member of the robusta species group in the virilis-repleta radiation, has a wide distribution from northern India throughout China to the Far East. Phylogenetic analyses of mitochondrial ND2 gene sequences revealed two genetically significantly diverged lineages with 2.1% DNA sequence divergence. These two lineages are largely allopatric: one is mainly found in southwest China (lineage A), whereas the other ranges central and east of China to northeast Asia (lineage B). The geographic distributions of these two clades narrowly overlap near the provincial boundaries of Yunnan and Guizhou or Guangxi, probably as a consequence of population expansion and secondary contact. These two lineages were estimated to have diverged about 0.56 Mya, and the estimated time of expansion was approximately 70,000 years ago for lineage A population, and 110,000 years ago for lineage B population. The present molecular analysis, together with nearly complete reproductive isolation between those two lineages, strongly suggests that the two lineages might be incipient species.     

中国烟草根黑腐病菌根串珠霉菌群及rDNA-ITS序列分析

从国内不同烟区分离获得烟草根黑腐病菌根串珠霉45个野生型和11个白色变异菌株,参照Punja & Sun的分群鉴定方法,对这56个菌株进行了分群鉴定。结果表明：中国根串珠霉分离株存在明显形态变异,共划分出6个群,其中群Ⅰ、Ⅱ、Ⅲ为野生型,群Ⅳ、Ⅴ为白色变异型;另有白色变异型HLL-1￠不同于其他各群,将其建为新群—群Ⅵ。统计分析发现,群Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ及Ⅵ的分离频率分别占42.9%、33.9%、3.6%、16.0%、1.8%和1.8%。群Ⅰ主要分布重庆和云南,群Ⅱ在5个调查省市均有分布,群Ⅲ、群Ⅴ仅分布     

Postglacial colonization of Northern Europe by distinct phylogeographic lineages of the bullhead, Cottus gobio

Three major phylogeographic lineages of the cottid fish Cottus gobio (bullhead) were identified in northern Europe from mitochondrial DNA sequences and allozyme data. The largely separate freshwater distributions of the lineages demonstrate distinct postglacial colonization histories. West of the Baltic Sea, Swedish lakes were invaded from the southwest (Germany). Another, eastern lineage has colonized the inland waters northeast and east of the Baltic, from refugia in northwest Russia; this lineage comprises a distinct subgroup found only from Estonia. The third lineage, found south and southeast of the Baltic, probably descended from rivers draining to the Black Sea from the north (e.g. Dnepr). In coastal waters of the Baltic Sea, and in near-coast inland waters, the lineages are now found intermixed in various combinations. The alternating fresh- and saltwater phases of the Baltic basin have variously enabled and disabled the use of coastal waters as colonization routes. Hypotheses on the chronology of dispersal and lineage mixing can be based on the distribution of the marker genes and the paleohydrographical record. The diversity of the Fennoscandian bullhead thus comprises anciently diverged (probably mid-Pleistocene) refugial lineages that in their freshwater range constitute distinct evolutionarily significant units. The thorough mixing of the various genomic origins in and around the Baltic, however, refutes the controversial view of distinct species status for the western and eastern ('Cottus koshewnikowi') bullheads. The postglacial contact of the lineages has created new diversity that cannot be interpreted in a conventional hierarchical framework of taxonomic or conservation units.     

中国资源再生利用的生态效率演变特征与空间分异格局

解析资源生态效率演变特征和分异格局,可为我国实现资源再生利用区域均衡发展和提高生态利用效率水平提供参考。本研究以26个省(市、区)的资源再生利用面板为对象,采用超效率DEA模型测算了2004—2017年其产业生态效率水平,并基于地理区划,分析该产业生态效率演变特征和空间分异格局。结果表明: 2004—2017年,研究区的资源再生利用产业生态效率逐年提高,约有年均1.5%的增长势能,整体表现为由内陆逐渐向沿海递增的演变态势。该产业生态效率全局空间相关性显著,且省(市、区)之间存在明显的空间集聚特征;随着年份推移,区域差异性减弱,高水平省(市、区)辐射带动力较强。研究期间,我国资源再生利用的生态效率空间分异趋于缓和,主要因为华北、东北、华东、华南、华中和西北地区的空间分异减弱,而西南地区的分异不断增强,从而弱化了整体降低趋势。     

Genetic diversity in parthenogenetic triploid Paragonimus westermani

Paragonimus westermani is a medically important foodborne trematode occurring throughout southeast Asia. We have used molecular techniques to test the hypothesis that the parthenogenetic triploid form of P. westermani has arisen only once. Sources of data for comparison were: (a) restriction fragment length polymorphisms (RFLPs) of ribosomal internal transcribed spacers (ITS); and (b) 'fingerprint' patterns observed when genomic digests were probed with simple sequence repeats (ATT)10 and (ATGT)7. In all cases there were distinct differences among triploid isolates from southwest Japan, northeast China and Korea. These findings are considered in the context of previous cytogenetic, allozyme, mitochondrial-RFLP and partial cytochrome c-oxidase subunit I (COI) sequence studies and indicate that triploid lineages may have arisen independently on more than one occasion. We favour this view. An alternative explanation is that the triploids did have a single origin, but that different clonal lineages have undergone subsequent mutations.     

坡向对四川冶勒红豆杉种群分布格局的影响——基于斑块信息的分析

在斑块信息的基础上,利用GIS技术分析了坡向对四川冶勒红豆杉种群分布格局的影响.结果表明,冶勒红豆杉种群主要分布在西北向、东北向、东向和北向斑块上,这些斑块在分布面积、平均斑块大小、平均斑块周长以及红豆杉个体的分布数量方面均占绝对优势.红豆杉种群的分布同坡向之间存在极显著的关联性,种群优先分布于北坡、东北坡、西北坡和东坡斑块,其次为西坡和西南坡斑块,最后为平地和东南坡斑块.冶勒红豆杉种群的分布格局绝大多数为聚集分布(除南向斑块外).其中,种群聚集强度最大的是北向斑块,其CE值高达0.906,其次为东北向、西北向斑块,其CE值分别为0.797和0.563,而其余坡向斑块上的CE值均低于0.5.聚集强度CE值与斑块数量、斑块总周长以及斑块上分布的红豆杉个体数呈显著正相关(相关系数分别为0.936、0.735和0.802),而与斑块面积、平均斑块大小、平均斑块周长、平均形状指数无显著相关.     

Phylogeny and taxonomy of the North American clade of the Ceratocystis fimbriata complex

Ceratocystis fimbriata is a widely distributed, plant pathogenic fungus that causes wilts and cankers on many woody hosts. Earlier phylogenetic analyses of DNA sequences revealed three geographic clades within the C. fimbriata complex that are centered respectively in North America, Latin America and Asia. This study looked for cryptic species within the North American clade. The internal transcribed spacer regions (ITS) of the rDNA were sequenced, and phylogenetic analysis indicated that most isolates from the North American clade group into four host-associated lineages, referred to as the aspen, hickory, oak and cherry lineages, which were isolated primarily from wounds or diseased trees of Populus, Carya, Quercus and Prunus, respectively. A single isolate collected from P. serotina in Wisconsin had a unique ITS sequence. Allozyme electromorphs also were highly polymorphic within the North American clade, and the inferred phylogenies from these data were congruent with the ITS-rDNA analyses. In pairing experiments isolates from the aspen, hickory, oak and cherry lineages were interfertile only with other isolates from their respective lineages. Inoculation experiments with isolates of the four host-associated groupings showed strong host specialization by isolates from the aspen and hickory lineages on Populus tremuloides and Carya illinoensis, respectively, but isolates from the oak and cherry lineages did not consistently reveal host specialization. Morphological features distinguish isolates in the North American clade from those of the Latin American clade (including C. fimbriata sensu stricto). Based on the phylogenetic evidence, interfertility, host specialization and morphology, the oak and cherry lineages are recognized as the earlier described C. variospora, the poplar lineage as C. populicola sp. nov., and the hickory lineage as C. caryae sp. nov. A new species associated with the bark beetle Scolytus quadrispinosus on Carya is closely related to C. caryae and is described as C. smalleyi.     

A Study on the Genus Astilbe Buch.-Ham. ex D. Don from China

The Astilbe Buch.-Ham. ex D. Don was founded in 1912. There are now 18 species throughout the world. USSR, Thailand, Indonesia, Bhutan, Nepal d Kashanmir each has only 1 species; Korea, Philippines and USA each has 2; India 3; Japan 6; and China 7 (including 3 endemics and 1 new variety). And northeast China, north China and northwest China each has 2; central China and southwest China each 4; eastern China 5. Thus the distribution centre of this genus seems to be in the region covering Japan and eastern, central, and southwest China. This genus is divided into two sections: Sect. Simplicifoliae Engl. and Sect. Astilbe. Sect. Simplicifoliae may be considered as the primitive one because it has 5 ordinary petals. This section consists of about 10 species: 5 in China (east China 4; southwest China 3; central China, north China and northeast China each 2; Northwest China 1), 5 in Japan, 2 in Korea, 1 in Philippines and India each. According to the distribution of this section, the author suggests that the centre of origin of this genus be in the forested parts from Japonthrough east China to southwest China.