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S SPIEGEL D HOLLAND Y TAM I BAR-YAAKOV L MASLENIN A ROSNER 《The Annals of applied biology》2004,144(2):229-236
Prunus necrotic ringspot virus (PNRSV) was detected in almonds, plum and apricot germplasm accessions and local almond cultivars in Israel. PNRSV was widespread both in wild and cultivated almond trees and uncommon in wild apricots and plums. The possible variation among the PNRSV isolates was initially evaluated by restriction analysis of PCR products representing the CP gene with the endonuclease RsaI and followed by nucleotide sequence analysis of selected isolates. It was concluded that all 13 isolates belong to group PV96, the largest cluster of PNRSV isolates, described previously. Two PNRSV isolates, one from a plum accession and one from an almond cultivar, were found to be distinct members of group PV96 with unique nucleotide modifications not found in other documented isolates of this virus. However, no PNRSV isolate typical to a specific host and/or to the Middle East region could be identified. This study expands the body of data on variability of PNRSV isolates and highlights the importance of assessing the virus status of germplasm collections by applying reliable diagnostic and differentiating methods. 相似文献
3.
The examination of the state of conservation of works of art in stone includes the assessment of the presence of microbiological agents on the surface of the decayed monuments. These microorganisms can accelerate, via their metabolic activity, the decay process of the stone surface. At present this assessment is made with the traditional techniques for the microbiological examination of the soil, provides results only after a delay of 30 days. A bioluminescent ATP assay should provide rapid quantitation of actively growing organisms on the surface of a stone monument, and the applicability of this technique was verified on some samples of sandstone (Pietraforte) collected from a historic building (the Strozzi Palace) in Florence. These samples were evaluated for the amount of the ATP and the total number of microorganisms. The results obtained suggest that the bioluminescent assay could be suitable for detecting and quantitating the presence of microorganisms in a sample of stone. 相似文献
4.
山东莒南发现的石制品 总被引:2,自引:1,他引:1
本文报道的128件人工石制品分别采自山东莒南县的石莲子乡烟敦岭和扁山乡九顶莲花山两个地点。石制品常见类型有边刮器,端刮器和砍斫器等,另有少量的雕刻器和尖状器,内含典型细石器。就石制品的组合及工艺水平而言,其时代可能属于旧石器时代末期。 相似文献
5.
DISCOVERY OF VERTEBRATE FOSSILS AND PALEOLITHIC ARTIFACTS IN DANJIANG SUBMERGING AREA AND ITS IMPLICATIONS 总被引:1,自引:1,他引:0
IntheareatobefloodedinthesecondengineeringstagefortheDanjiangreservoir,wediscovered16vertebratefossillocalitiesand52Paleolithicsitesin1994,andcollected603artifactsandmanyfossils.Ofthel6new1yfoundvertebratefossillocalities,threearereptilesitesrepresentedbydinosaureggsandlimbbones,andl3producemamma1s,including4Pale0gene,2Ne0geneand7Quaternarysites'ThemammalianlocalitiesareofPale0cene,Eocene,EarlyMiocene,andPli0ceneorEarlyPleistocene,MiddleandIntePleistocene,respectively.Theyfillinsomestrat… 相似文献
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Suzuki Setsuko Kyoko Sugai Ichiro Tamaki Koji Takayama Hidetoshi Kato Hiroshi Yoshimaru 《Molecular ecology》2020,29(6):1050-1068
Pandanus boninensis, endemic to the Ogasawara Islands, Japan, is distributed on both the older Bonin and younger Volcano Islands. In this study, we conducted population genetic analyses of P. boninensis on these islands to examine the population diversity and structure across old and young islands, to assess potential differences in population demography with island age, and to collect any evidence of migration between old and young islands. We found that the genetic diversity of expressed sequence tag (EST)–based microsatellite (SSR) markers, the nucleotide diversity of nuclear DNA sequences, and the haplotype diversity of chloroplast DNA on young islands were lower than those on old islands. Clustering analyses of EST‐SSR indicated that populations on old islands were strongly diverged from those on young islands. Approximate Bayesian computation analysis of EST‐SSR suggested that population expansion occurred on old islands while population reduction occurred on young islands. We also found evidence of migration among old islands (mostly from south to north), while it appears that there have been very few migration events between old and young islands. These differences could be due to the fact that young islands tend to be geographically isolated and support smaller populations that began a shorter time ago from limited founders. The P. boninensis populations on the Volcano Islands are interesting from an evolutionary perspective as they constitute a classic example of the early stages of progressive colonization on oceanic islands with small effective population sizes and low genetic diversity. 相似文献
8.
《Nucleosides, nucleotides & nucleic acids》2013,32(8-9):1127-1129
The liquid chromatography‐mass spectrometry (LC‐MS) following on from the two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE) technique was applied for the analysis of proteins in a renal stone found in a hyperuricemic patient. This technique was sensitive enough to detect small quantities of proteins even in a renal stone. 相似文献
9.
Hasan Hosseinzadeh Saeid Nasrollanejad Zahra Dordiani Vahid Jamshidnezhad 《Archives Of Phytopathology And Plant Protection》2013,46(16):1879-1883
Sharka disease is one of the most damaging diseases of fruit trees in the world, which is caused by Plum pox virus (PPV) that belongs to the genus Potyvirus in the family Potyviridae. Each year, this virus decreases the yield and causes substantial economic damages to its host plants worldwide. This virus is quarantined in Iran but in recent years, suspicious symptoms of the disease were observed in different grown areas, such as Golestan province. During 2010, 420 samples with mosaic, chlorosis, necrosis, ring pattern, blotches, etc. symptoms were collected from the gardens in Golestan province that included 100 samples from plum, 100 from peach and 240 from nectarine. These samples were evaluated using a double-antibody sandwich-ELISA (DAS-ELISA) method and a polyclonal antibody. The results of this survey indicated that among the total of 420 samples, none of them showed positive reaction in DAS-ELISA test. 相似文献
10.
Stone fruits and pome fruits are cultivated commercially worldwide. In India, they are grown in temperate regions, which mainly includes Jammu and Kashmir, Uttarakhand, Himachal Pradesh and some North-Eastern states. In this study, an attempt has been made to identify the Prunus necrotic ringspot virus (PNRSV) infecting stone and pome fruits in India and to characterise them on the molecular level. Surveys were conducted in the temperate fruit-growing areas and incidence of PNRSV was detected by serological and molecular means in almond, apple, cherry, nectarine, peach, plum and wild cherry. Further diversity analysis of PNRSV was performed using bioinformatics tools such as clustalW, DNA Data Bank of Japan, MultAlin and Recombination Detection Programme. PNRSV was detected in plum, peach, cherry, almond, nectarine, wild cherry and apple. In the diversity analysis study on the basis of coat protein gene, it was found that the isolates showed identity levels from 82 to 100%. In a plum isolate, a stretch of amino acids from 207 to 221 was found variable from Indian and other isolates. In one of the Indian apple isolates, “NR” repeats at 41–44 position (characteristic of PV-32 group, Group I) were identified. Phylogenetic analysis revealed that Indian isolates are falling in Group-I. Movement protein was also amplified from peach and multiple alignment studies showed that N-terminus was mostly conserved, whereas the C-terminal was highly variable. 相似文献