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71.
大栏养猪微生物发酵床垫料中青霉菌的分离与鉴定   总被引:1,自引:0,他引:1  
为了解大栏养猪微生物发酵床垫料中青霉菌的种类情况,筛选有益青霉菌用于指导管理生猪健康生长。本研究从福建省福州市福清和永泰2个基地共采集了106份垫料样品,分离其中的青霉菌。对不同样品中分离到菌株根据菌落形态初步归类后,从不同菌落类群中选出代表性的3个菌株,采用菌落形态与菌体形态特征,结合β-微管蛋白基因(BenA)序列分析进行鉴定。结果表明,这3株青霉菌中2株为橘青霉菌Penicillium citrinum,1株为爪哇正青霉菌Eupenicillium javanicum。  相似文献   
72.
 潜根线虫(Hirschmanniella spp.)是一类寄生于水稻根部的重要病原线虫,在我国多个省份和地区皆有分布,然而江苏稻区有关该线虫发生和危害鲜有报道。从江苏省农科院水稻实验田采集的水稻根部分离到大量潜根线虫,利用光学和扫描电镜显微观察确定所分离到的线虫优势种群为细尖潜根线虫(Hirschmanniella mucronata),de-Man形态学数据显示江苏分离群体与其他已报道的H. mucronata分离群体具有一定差异,但基本处于标准模式值范围。分别对ITS-rRNA、28S rRNA D2-D3扩展区、18S rRNA、细胞色素氧化酶c亚基I(COI)和热激蛋白90(Hsp90)序列进行PCR扩增,新获得的H. mucronata ITS序列与中国台湾和比利时分离群体具有高度相似性,同时比较各分离群体的ITS1、5.8S和ITS2序列碱基变异,显示我国江苏、台湾和比利时群体差异最小。基于28S rRNA D2-D3扩展区、18S rRNA和ITS-rRNA序列构建的贝叶斯和最大似然进化树将潜根线虫划分为3个进化分支,与已报道的其他H. mucronata种群共同位于第二分支。  相似文献   
73.
红树林内生真菌1403的形态与分子鉴定(英文)   总被引:3,自引:1,他引:2  
红树林内生真菌1403是从中国南海分离的一株镰刀菌,在液体发酵条件下能够产生灰黄霉素和葸醌类的抗生素。基于1403在形态学方面具有以下特征:产小型分生孢子的分生孢子梗较长,小型分生孢子呈椭圆形,大型分生孢子线形或略微弯曲,本文将它与有类似形态特征的镰刀菌进行了比较,发现1403与植物病原菌Fusarium verticillioides(有性态为Gibberella moniliforme)表面上很相似,气生菌丝均可产生大量假头状或链状的小型分生孢子,但深入的研究却发现1403与F.verticillioides具有不同的性状,如产生的多生分生孢子梗有时与单生分生孢子梗长度相当,产生环状菌丝,以及菌丝发生融合等现象,进一步以最大简约法和贝叶斯分析法将1403与其它相似镰刀菌进行系统发育比较,综合18S、28S、ITS三水平上的分析结果可以将1403归于镰刀菌亚组Gibberella fujikuroi,并最终在EF—1α水平上将其定为Fusarium proliferatum.  相似文献   
74.
The 18 species of bird studied originally are known to belong to muscicapids, robins and sylviids of passerines, but some dis- putations are always present in their classification systems. In this experiment, phylogenetic relationships of 18 species of passerines were studied using Adenylate Kinase lntron 5 (AKS) sequences and DNA techniques. Through sequences analysis in comparison with each other, phylogenetic tree figures of 18 species of passerines were constructed using Neighbor-Joining (N J) and Maximum-Parsimony (MP) meth- ods . The results showed that sylviids should be listed as an independent family, while robins and flycatchers should be listed into Musci- capidae. Since the phylogenetic relationships between long-tailed tits and old world warblers are closer than that between long-tailed tits and parids, the long-tailed tits should be independent of paridae and be categorized into aegithalidae. Muscicapidae and Paridae are known to be two monophylitic families, but Sylviidae is not a monophyletic group. AK5 sequences had better efficacy in resolving close relationships of interspecies among intrageneric groups.  相似文献   
75.
Mangrove endophytic fungus 1893 was isolated from Kandelia candel from an estuarine mangrove on the South China Sea Coast. Two new lactones 1893A and 1893B, together with other known compounds, have been isolated from its fermentation broth. To classify the endophyte correctly for further industrial application, a combination of morphological and molecular techniques was used to approach its identity. The endophyte was compared with similar species having trichogynes or trichogyne-like hyphae which apparently fused with antheridium-like hyphae, and perithecia initials developing from an ascogonial coil surrounded by enveloping hyphae in early developmental stages on pure culture. Further morphological characteristics on host and non-host were used for comparison with similar species when the endophyte was cultivated on leaves of Kandelia candel and Mangifera indica, respectively, which resulted in classifying the endophyte as a Phomopsis species. The ITS sequence of rDNA was used to infer its phylogenetic relationships with Phomopsis species that resembled the strain in morphology or ecology. Finally, the endophyte was identified as Diaporthe phaseolorum var. sojae based on morphological and molecular evidence. Our study is a first report of Diaporthe phaseolorum var. sojae isolated from mangrove Kandelia candel. Foundation item: The search was supported partly by the Guangzhou Natural Science Foundation (Grant No. 2007Z3-EO581), the Guangdong Provincial Natural Science Foundation (Grant No. 2007A0200300001-7), the Chinese High-Tech 863 Project (Grant No. 2006AA09Z422), and the National Natural Science Foundation of China (Grant No. 20572136). The first two authors have the same contribution.  相似文献   
76.
测定了宽身大眼蟹和日本大眼蟹线粒体12S rRNA基因部分片段的序列,前者为577 bp, 后者为572 bp.二者的核苷酸序列A、T、G、C的含量相似,分别为39.0%、35.7%、16.5%、8.8%;39.3%、 36.2%、 15.8%、8.7%;不包括11处插入/缺失位点,两序列间有75个变异位点,核苷酸差异率为13.18%,其中转换42个、颠换33个, 转换与颠换比约为1.3.对国内外4种大眼蟹长度为331 bp的12S rRNA基因同源序列进行分析,A+T的平均含量为76.6%,明显高于G+C的平均含量,且存有变异位点52个,简约信息位点25个.系统发生树的拓扑结构显示,所有的大眼蟹聚为一支,支持大眼蟹类为一单系.  相似文献   
77.
As the fast pace of genomic research continues to identify mitochondrial lineages in animals, it has become apparent that many independent studies are needed to support a robust phylogenetic inference. The aim of this study was thus to further characterize the maternal lineage, proposed to originate in southwestern region of China, using a wider survey of diverse goat breeds in China. To this end, we sequenced the mitochondrial hypervariable region 1 (HVR1) of the mtDNA control region in 145 goats of 12 Chinese breeds. Phylogenetic analysis revealed that Chinese goats were classified into four distinct lineages (A, B, C and D) as previously reported. A Mantel test and the analysis of Analysis of Molecular Variance (ANOVA) indicated that there was not an obvious geographic structure among Chinese goat breeds. Population expansion analysis based on mismatch distribution and Fu's Fs statistic indicate that two expansion events in Chinese goats occurred respectively at about 11 and 29 mutational time units ago, revealing two star-like subclades in lineage B corresponding to two population expansion events. Moreover, lineage B sequences were presented only in the breeds of southwestern or surrounding regions of China. Multiple lines of evidence from this study and previous studies indicate that for Chinese goats mtDNA lineage B originated from the southwestern region of China.  相似文献   
78.
圆斑星鲽线粒体基因组全序列结构及其进化   总被引:3,自引:2,他引:1       下载免费PDF全文
利用圆斑星鲽(Verasper variegatus Temminck et Schlegel)和相关鱼类的部分线粒体基因序列,设计出6对扩增引物,通过PCR扩增产物直接测序和引物行走(Primer walking)法测定圆斑星鲽线粒体基因组全序列,并对其进行结构与进化分析。圆斑星鲽线粒体基因组序列长17273 bp,其基因序列及构成都与其他硬骨鱼基本相同,包括37个基因(2个rRNA基因、22个tRNA基因和13个蛋白质编码基因)和2个非编码区(控制区和WANCY区)。在22个tRNA基因中,tRNAGln、tRNAAla、tRNAAsn、tRNACys、tRNATyr、tRNASer(第2个)、tRNAGlu和tRNAPro的编码基因位于L链上,其余则位于H链上。在13个蛋白质编码基因中,除了COⅠ基因的起始密码子为GTG外,其余均以ATG为起始密码子。蛋白质编码基因包括具有完整TAA终止密码子的ND1,COⅠ,ATP8,ND4L,ND5,而其他蛋白编码基因则具有不完全终止密码子。在L链上,ND6是仅有的一个蛋白质编码基因。圆斑星蝶的控制区包含1个终止相关序列区(ETAS)、6个中央保守序列区(CSB-A、B、C、D、E、F)和3个保守序列区(CSB-1、2、3)以及长串联重复区(Tandemly repeat sequence)。用NJ法和MP法对5个目22种鱼mtDNA的13个蛋白质编码基因的氨基酸序列进行系统分析,结果显示,圆斑星蝶与石鲽关系最近,鲽形目的鲆、鲽类与鲈形目的科(Carangidae)、鲷科(Sparidae)鱼类亲缘关系较近,而同属于鲽形目的塞内加尔鳎(Solea senegalensis)没有和任何目聚在一起,成为一个独立的分支。圆斑星蝶的基因组全序列序列已提交到GenBank,登录号为DQ403797,控制区单元型序列的GenBank登录号为DQ834444~7。  相似文献   
79.
Genetic variability in melon based on microsatellite variation   总被引:8,自引:0,他引:8  
A set of 18 simple‐sequence repeat (SSR or microsatellite) markers was used to study genetic diversity in a collection of 27 melon (Cucumis melo L.) accessions, representing a broad range of wild and cultivated melons. The materials studied were highly polymorphic for SSRs and a total of 114 alleles were detected (average of 6.3 alleles per locus). Cluster analysis suggests the division of these accessions into two major groups, largely corresponding to the division of C. melo in the two subspecies agrestis and melo. The assignment of the accession to the subspecies was generally in agreement with published reports, except for those corresponding to the ‘dudaim’ and ‘chito’ cultivar groups, which, according to the observed SSR variability, should be included in subspecies agrestis. Based on cluster analysis, five groups of accessions were defined. The two most divergent groups include mainly accessions from the Mediterranean which form one group, and accessions from China, Japan, Korea and India forming the other. Both groups shared a low level of intra‐accession variation compared with the other groups, which suggests an erosion of their genetic variability because of drift and/or inbreeding. The remaining accessions, mainly from Central Africa and India, were more variable and may be an important source of genetic variation for melon breeding.  相似文献   
80.
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