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1.
Yeasts, isolated from different sources, were identified and tested for inhibition using YMA-MB plates seeded with Botrytis cinerea strains. A total of 42 yeast strains of 20 different species were tested in vitro for antagonism against 18 pathogenic B. cinerea strains. Pichia membranifaciens, P. anomala and Debaryomyces hansenii displayed the most important inhibitory effect against Botrytis strains. In small-scale trials, post-harvest application of P. membranifaciens CYC 1106 to apple wounds inhibited B. cinerea CYC 20010. Purified killer toxin from P. membranifaciens CYC 1106 inhibited B. cinerea CYC 20010. Results indicated that certain yeasts, or their toxins such us P. membranifaciens CYC 1106 killer toxin, might have potential as novel agents to control B. cinerea.  相似文献   

2.
季东超  宋凯  邢晶晶  陈彤 《植物学报》2015,50(5):628-636
溶解素基序(LysM)是一类普遍存在于大多数有机体中的蛋白质结构域。植物细胞中含有LysM结构域的蛋白能够识别不同种类含有N-乙酰葡糖胺结构的配体分子,从而启动植物对病原菌的特异防御反应。作为一种重要的模式识别受体,LysM结构域蛋白通过不同形式的寡聚化、受体类胞质激酶BIK1和MAPK级联反应向下游传递信号,而病原菌能够通过其分泌的效应蛋白特异性识别或修饰模式识别受体,规避植物细胞中病原体相关分子模式诱导的免疫反应。该文主要综述受体激酶/蛋白在病原菌激发子识别和防卫反应启动中的作用。  相似文献   

3.
异担子菌属Heterobasidion种类是北半球针叶树最严重的森林病原菌,在世界范围内能侵染27种针叶树,对欧洲和北美洲的经营林已造成重大损失。基于传统形态学研究,认为异担子菌属有2个种,即多年异担子菌H. annosum和岛生异担子菌H. insulare,然而单孢交配实验研究证明2个种为复合种。分子系统发育分析研究表明:异担子菌属包括15个种,其中5个种为森林病原菌[冷杉异担子菌H. abietinum、多年异担子菌(狭义)H. annosum s. str.、变孔异担子菌H. irregulare、西方异担子菌H. occidentale和小孔异担子菌H. parviporum];10个种为腐生菌(淀粉孢异担子菌H. amyloideum、南洋杉异担子菌H. araucariae、阿曼德异担子菌H. armandii、南方异担子菌H. australe、岛生异担子菌H. insulare、林芝异担子菌H. linzhiense、东方异担子菌H. orientale、拟岛生异担子菌H. subinsulare、拟小孔异担子菌H. subparviporum和西藏异担子菌H. tibeticum)。多年异担子菌(狭义)H. annosum s. str.、小孔异担子菌H. parviporum和冷杉异担子菌H. abietinum分布于欧洲,分别是松属、云杉属和冷杉属林木的病原菌。变孔异担子菌H. irregulare和西方异担子菌H. occidentale分布于北美洲,前者侵染松属和柏属树木,后者侵染冷杉属、铁杉属、黄杉属和巨杉属树木。虽然广义的多年异担子菌H. annosum sensu lato曾在我国报道,但基于目前研究结果表明该种为拟小孔异担子菌H. subparviporum。目前世界上最具侵染力的5种病原菌即狭义的多年异担子菌H. annosum s. str.、小孔异担子菌H. parviporum、冷杉异担子菌H. abietinum、变孔异担子菌H. irregulare和西方异担子菌H. occidentale还未在我国发现,也未列为对外检疫对象,因此建议将其列为进境植物检疫性有害生物。RNA聚合酶II大亚基序列(RPB1)在异担子菌属种类鉴定中敏感性和特异性最高,研究证明该分子方法可应用于鉴别不同异担子菌种类的有效基因标记,在海关部门进行原木和木质产品的检疫中可运用该分子标记进行林木病原异担子菌的检测。  相似文献   

4.
本文报道了分布于西藏的4个中国新记录种, 即须弥四带芹(Tetrataenium wallichii)、巴洛特栎(Quercus baloot)、尼泊尔姜味草(Clinopodium nepalense)和喜马拉雅耳稃草(Garnotia emodi); 以及24个西藏新记录种, 即翼叶棱子芹(Pleurospermum decurrens)、线叶球兰(Hoya linearis)、尼泊尔菊三七(Gynura nepalensis)、一枝黄花(Solidago decurrens)、拟游藤卫矛(Euonymus vaganoides)、云南木鳖(Momordica subangulata subsp. renigera)、马㼎儿(Zehneria japonica)、攀援胡颓子(Elaeagnus sarmentosa)、四棱猪屎豆(Crotalaria tetragona)、大叶千斤拔(Flemingia macrophylla)、毛喉鞘蕊花(Coleus forskohlii)、独龙木姜子(Litsea taronensis)、长序大苞兰(Bulbophyllum purpureofuscum)、球花石豆兰(B. repens)、黄兰(Cephalantheropsis obcordata)、双角厚唇兰(Dendrobium forrestii)、密花兰(Diglyphosa latifolia)、云南盆距兰(Gastrochilus yunnanensis)、扁茎羊耳蒜(Liparis assamica)、耳唇兰(Otochilus porrectus)、疏花无叶莲(Petrosavia sakuraii)、长序羊角藤(Gynochthodes lacunosa)、黑蒴(Alectra avensis)和赤杨叶(Alniphyllum fortunei), 其中无叶莲科为西藏新记录科, 一枝黄花属(Solidago)、马㼎儿属(Zehneria)、千斤拔属(Flemingia)、鞘蕊花属(Coleus)、密花兰属(Diglyphosa)、无叶莲属(Petrosavia)、羊角藤属(Gynochthodes)、黑蒴属(Alectra)和赤杨叶属(Alniphyllum)等9个属为西藏新记录属。凭证标本均存放于中国科学院昆明植物研究所标本馆(KUN)。  相似文献   

5.
Poa sect. Poa subsect. Nivicolae (Prob.) Tzvelev was circumscribed to include four species of the Soviet Union: Poa shumushuensis, Poa caucasica, Poa irkutica, and Poa veresczaginii. Bayesian phylogenetic analyses of plastid and nuclear‐ribosomal DNA revealed that it is polyphyletic, none of these species are closely related. Poa shumushuensis, type of sect. Nivicolae, or its ancestor, likely displayed the nrDNA genotype characteristic of the higher polyploid P. sect. Malacanthae. Genotype codes are designated for each species: Hx, C c, Php, and Shp. Poa sect. Nivicolae s.s. is restricted to P. shumushuensis; P. sect. Irkuticae is restricted to P. irkutica; P. caucasica is moved to P. subg. & sect. Caucasicae nov.; and P. sect. Dschungaricae is resurrected for P. veresczaginii and two other species. Although diclinous breeding systems are known in many western hemisphere species of Poa, dicliny is infrequent and little studied in Asian Poa. Poa shumushuensis is judged to be either sequentially gynomonoecious or gynodioecious. A ratio of 2 perfect‐, to 2 mixed‐, to 1 pistillate‐flowered inflorescences from different plants in P. shumushuensis is suggestive of a recessive allele for stamen suppression, and this is associated with subtle sexual‐dimorphism. Poa irkutica is diclinous with a breeding system between simple gynomonoecy and sequential gynomonoecy; P. caucasica is perfectly flowered; and P. veresczaginii has infrequent abortive anthers, indicative of limited dicliny, or sterility for other reasons possibly related to its reticulate origin. In total, 23 Asian species are here reported to be diclinous and their breeding systems are characterized. A lectotype is designated for P. fauriei.  相似文献   

6.
Nearly 60 compression fossils of the vegetative stems and fertile zones of Spencerites (Scott) emend. are described from the Bolsovian of the Kladno-Rakovník and Radnice basins in the Czech Republic. Spencerites is re-interpreted as a pseudoherbaceous, repeatedly (minimum three times) dichotomously-branching, lycopsid with fertile apical zones. Vegetative stems are described for the first time. Two new species are proposed: Spencerites havlenae and Spencerites chaloneri. They are generally similar morphologically, and can be distinguished mainly by their isospores. Spencerisporites radiatus Felix and Parks, 1959 emend. isospores were isolated from Spencerites havlenae and Spencerisporites striatus sp. nov. from Spencerites chaloneri. Emendations are proposed for the generic diagnoses of Spencerites and Spencerisporites, and the specific diagnosis of Spencerisporites radiatus.  相似文献   

7.
The effects of mutations in five anterior gap genes (hkb, tll, otd, ems and btd) on the spatial expression of the segment polarity genes, wg and hh, were analyzed at the late blastoderm stage and during subsequent development. Both wg and hh are normally expressed at blastoderm stage in two broad domains anterior to the segmental stripes of the trunk region. At the blastoderm stage, each gap gene acts specifically to regulate the expression of either wg or hh in the anterior cephalic region: hkb, otd and btd regulate the anterior blastoderm expression of wg, while tll and ems regulate hh blastoderm expression. Additionally, btd is required for the first segmental stripe (mandibular segment) of both hh and wg at blastoderm stages. The subsequent segmentation of the cephalic segments (preantennal, antennal and intercalary) appears to be dependent on the overlap of the wg and hh cephalic domains as defined by these gap genes at the blastoderm stage. None of these five known gap genes are required for the activation of the labral segment domains of hh and wg, which are presumably either activated directly by maternal pathways or by an unidentified gap gene.  相似文献   

8.
《FEBS letters》1994,350(2-3):333-336
The kinetic properties of MSS4 are studied in comparison with those of Rab3A GRF. MSS4 stimulates the dissociation of [3H]GDP from the lipid-modified and lipid-unmodified forms of Rab3A to the same extent, although Rab3A GRF is more effective on the lipid-modified form than on the lipid-unmodified form. Both MSS4 and Rab3A GRF are inactive on other Rab/Sec/Ypt family members including at least Rab2, Rab5, and Rab11. Rab GDI inhibits the MSS4 and Rab3A GRF effects on the lipid-modified form of Rab3A, but the doses of Rab GDI necessary for this inhibitory effect on Rab3A GRF are lower than those on MSS4. Moreover, Rab GDI slightly inhibits the Rab3A GRF effect on the lipid-unmodified form of Rab3A, but does not affect the MSS4 effect on the lipid-unmodified form of Rab3A. These results suggest that MSS4 and Rab3A GRF are different GDP/GTP exchange proteins for Rab3A.  相似文献   

9.
在中国文衣科地衣系统研究中,对裂隙衣属Fissurina地衣进行了订正,报道了16种,其中中国新记录种3个,即连绵裂隙衣F. consentanea、球孢裂隙衣F. globulifica和皱体裂隙衣F. insidiosa。建议4个异名,即Fissurina isidiata Z.F. Jia 为Platythecium dimorphodes (Nyl.) Staiger的异名;Fissurina marginata Staiger为Fissurina elaocarpa (A.W. Archer) A.W. Archer的异名;Graphis canlaonensis Vain.为Fissurina consentanea Nyl.的异名;Graphis glauca Müll. Arg.为Fissurina dumastii Müll. Arg.的异名。本文提供了中国裂隙衣属每个种的描述和分布,并提供了鉴定检索表。  相似文献   

10.
Oresitrophe and Mukdenia (Saxifragaceae) are epilithic sister genera used in traditional Chinese medicine. The taxonomy of Mukdenia, especially of M. acanthifolia, has been controversial. To address this, we produced plastid and mitochondrial data using genome skimming for Mukdenia acanthifolia and Mukdenia rossii, including three individuals of each species. We assembled complete plastomes, mitochondrial CDS and nuclear ribosomal ETS/ITS sequences using these data. Comparative analysis shows that the plastomes of Mukdenia and Oresitrophe are relatively conservative in terms of genome size, structure, gene content, RNA editing sites and codon usage. Five plastid regions that represent hotspots of change (trnH-psbA, psbC-trnS, trnM-atpE, petA-psbJ and ccsA-ndhD) are identified within Mukdenia, and six regions (trnH-psbA, petN-psbM, trnM-atpE, rps16-trnQ, ycf1 and ndhF) contain a higher number of species-specific parsimony-informative sites that may serve as potential DNA barcodes for species identification. To infer phylogenetic relationships between Mukdenia and Oresitrophe, we combined our data with published data based on three different datasets. The monophyly of each species (Oresitrophe rupifraga, M. acanthifolia and M. rossii) and the inferred topology ((M. rossii, M. acanthifolia), O. rupifraga) are well supported in trees reconstructed using the complete plastome sequences, but M. acanthifolia and M. rossii did not form a separate clade in the trees based on ETS + ITS data, while the mitochondrial CDS trees are not well-resolved. We found low recovery of genes in the Angiosperms353 target enrichment panel from our unenriched genome skimming data. Hybridization or incomplete lineage sorting may be the cause of discordance between trees reconstructed from organellar and nuclear data. Considering its morphological distinctiveness and our molecular phylogenetic results, we strongly recommend that M. acanthifolia be treated as a distinct species.  相似文献   

11.
We have analyzed the relationship between autonomously replicating sequence (ARS) structure and function for three ARS (ARS605, ARS607 and ARS609) from chromosome VI of Saccharomyces cerevisiae by systematic XhoI-linker mutation in the ARS consensus sequence (ACS) and flanking sequences. All mutations that encroached upon the ACS destroyed ARS activity. DNA sequences stimulative for ARS function were identified on either side of the ACS of ARS605 and only on the 3'-side of the ACS of ARS607. In ARS609, however, no such stimulative sequences were observed. Base substitutions complementary to the wild-type sequence of those stimulative regions, in ARS605 and ARS607, that did not change the AG of unwinding nor affected ARS activity suggests that these regions have, at least, a function as DNA-unwinding elements (DUE). ARS605, ARS607 and ARS609 DNA are of low AG value and showed hypersensitivity to single-strand-specific nuclease when inserted in negatively supercoiled plasmid. Linker mutations inhibitory for ARS activity (5L11 and 7L14) also caused significant changes in local nucleotide (nt) sensitivity within the ACS and its adjoining regions. Complementary base substitutions, however, did not affect these changes in local nt sensitivity. These results imply that the stimulative regions flanking the ACS are necessary to produce an optimum conformation around the ACS which may be important for full ARS activity.  相似文献   

12.
Data for the flavonoids of 19 species in 10 sections of Ludwigia are presented. Eight flavonoids, comprising four glycoflavones, of which vitexin and isovitexin are reported for the first time in Ludwigia, and four flavonol glycosides, based on quercetin, are present in these species. Each section treated here has either glycoflavones or flavonols; presence of only onte class is considered to be advanced in the genus as a whole, compared with the presence of both glycoflavones and flavonols in the more generalized sects Myrtocarpus Cinerascentes, and Pterocaulon, which were examined earlier. Only glycoflavones are present in sects Macrocarpon (four species), Seminuda (five species), the ditypic African sect. Africana, the monotypic African sects Brenania, Cryptosperma, and Prieurea, the monotypic east Asian sect. Nipponia, and the monotypic pantropical section Fissendocarpa. Only flavonols are present in the monotypic Old Wodd section Caryophylloidea and sect. Oligospermum, which comprises nine species widespread in the OId and New Worlds.  相似文献   

13.
通过形态学比较和对ITS-nrDNA序列的分析,本文描述了产自我国热带及亚热带地区乳菇属的5个新种和1个中国新记录种。新种缘囊体乳菇Lactarius cheilocystidiatus和多囊体乳菇L. polycystis由于具有真正的囊状体而与变红乳菇亚属L. subg. Plinthogalus的绝大多数种相异,它们与泰国的L. crassiusculus关系密切。新种粘果乳菇L. gloeocarpus和多见乳菇L. vulgaris是乳菇亚属L. subg. Lactarius的新成员,其典型特征为淡黄色胶粘菌盖、孢子具网状纹饰和较大的囊状体,它们与原初描述自中国的淡黄褐乳菇L. pallido-ochraceus、淡环纹乳菇L. pallidizonatus以及印度的L. thindii形成种复合群。新种湖南乳菇L. hunanensis与温带物种具有较强的亲缘关系,它的典型特征为粘不规则交织型的盖表皮中具橄榄色被壳物质以及具斑马纹纹饰的孢子,属L. blennius种复合群。南方窝柄黄乳菇L. austroscrobiculatus原初描述自印度尼西亚,具有强烈的热带性质,这是在中国首次发现该种。本研究的标本采集自安徽、海南、河南、湖南、江西和云南。这些物种是中国-日本森林植物亚区的代表性乳菇类真菌。  相似文献   

14.
Phylogenetic affinities among Chilean Sophora species are not clear. We suggest a new hypothesis for the origin of the section Edwardsia on the basis of parsimony analysis, which allows a South American origin to be established for the species of this section. The seed alkaloid composition did not provide useful information for the filiation of Edwardsia species, and the shortest tree was obtained using morphological characters only. Two branches are clearly distinguishable by the pubescence of the leaflets and the flag/wings length ratio: one of them includes S. chrysophylla, S. tetraptera, S. toromiro, S. howinsula and S. denudata; the other one includes S. macnabiana, S. microphylla, S. masafuerana, S. prostrata and S. fernandeziana. In contrast, S. macrocarpa, an ancient element of the South American flora, is closely related to species belonging to the section Sophora represented in the region by S. tomentosa, S. linearifolia and S. rhynchocarpa. Sections Calia and Styphnolobium are clearly related to each other, both morphologically and chemically.  相似文献   

15.
目前对藏鼩鼱(Sorex thibetanus)和甘肃鼩鼱(Sorex catnsulus)的分布范围和生物学资料了解较少.2017年,在云南省西北部的高山区域采集了 48号鼩鼱属(Sorex)动物标本.用形态学和基于Cyt b基因的分子系统学对采集标本进行了物种鉴定.结果显示来自4个地点的27号标本形态上与藏鼩鼱相符...  相似文献   

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17.
迄今为止,以直翅目昆虫为寄主的虫草共报道25种,本研究详细介绍了它们的种类、寄主与分布,并给出了相关的分类学注释。ITS和tef1-α基因联合数据的分子系统发育显示,直翅目虫草分别隶属于白僵菌属Beauveria、绿僵菌属Metarhizium和线虫草属Ophiocordyceps 3个属。基于直翅目昆虫六大类群的生态习性特点,分析并讨论了直翅目虫草物种多样性与寄主的关系。以两种白僵菌Beauveria及戴氏虫草Metacordyceps taii(贵州绿僵菌Metarhizium guizhouense的异名)为例,介绍了虫草的根状菌索,一种介于子实体和孢梗束形体之间的根须状结构。种类修订:蟋螽白僵菌新组合Beauveria grylli comb. nov. ≡ 蟋蟀虫草Cordyceps grylli = Beauveria loeiensis,Beauveria kirkii comb. nov. ≡ Cordyceps kirkii。寄主更正:蟋螽白僵菌的寄主由原来的蟋蟀成虫(蟋蟀科Gryllidae)更正为螽斯(蟋螽)若虫(蟋螽科Gryllacrididae),蟋蟀线虫草Ophiocordyceps tettigonia 寄主由原来的螽斯成虫(螽斯科Tettigoniidae:螽斯属Tettigonia)更正为蟋蟀成虫(蟋蟀科)。  相似文献   

18.
Specimens belonging to the pycnogonid family Ammotheidae collected during the Victoria Land Transect 2004 cruise (Ross Sea, Antarctica) were studied. Five species are recognized in this collection, three species of Ammothea, one of Achelia and one of Austroraptus. Some information about the variability of the propodal armature of Ammothea glacialis is discussed. The rare species Ammothea meridionalis is reported for the fifth time, enlarging its known bathymetric range. A new species in the genus Ammothea is described, Ammothea victoriae. The new taxon is compared with its closest congeners, especially with A. armentis, A. gordonae and A. carolinensis. Both morphotypes of Achelia spicata are reported, some additional morphological differences having been detected between them. Austroraptus calcaratus is reported for the third time, and with our specimens 14 individuals are now known. Present and previous data show a restricted geographical and bathymetric distribution.  相似文献   

19.
The genes for FokI, a type-IIS restriction-modification system from Flavobacterium okeanokoites (asymmetric recognition sequence: 5'-GGATG/3'-CCTAC), were cloned into Escherichia coli. Recombinants carrying the fokIR and fokIM genes were found to modify their DNA completely, and to restrict lambdoid phages weakly. The nt sequences of the genes were determined, and the probable start codons were confirmed by aa sequencing. The FokI endonuclease (R · FokI) and methyltransferase (M · FokI are encoded by single, adjacent genes, aligned in the same orientation, in the order M then R. The genes are large by the standards of type-II systems, 1.9 kb for the M gene, and 1.7 kb for the R gene. Preceding each gene is a pair of FokI recognition sites; it is conceivable that interactions between the sites and the FokI proteins could regulate expression of the genes. The aa sequences of the N- and C-terminal halves of M · FokI are similar to one another, and to certain other DNA-adenine methyltransferases, suggesting that the enzyme has a ‘tandem’ structure, such as could have arisen by the fusion of a pair of adjacent, ancestral M genes. Truncated derivatives of M · FokI were constructed by deleting the 5'- or 3' -ends of the fokIM gene. Deleting most of the C-terminus of M · FokI produced derivatives that methylated only the top (GGATG) strand of the recognition sequence. Conversely, deleting most of the N-terminus produced derivatives that methylated only the bottom (CATCC) strand of the recognition sequence. These results indicate that the domains in M · FokI for methylating the two strands of the recognition sequence are largely separate.  相似文献   

20.
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