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1.
Sequences of two internal transcribed spacer regions between 18S and 28S rRNA for recently described yeasts species, Saccharomyces kunashirensis, S. martiniae, S. rosinii, and S. transvaalensis, were determined to assess their phylogenetic relationship to the other Saccharomyces species. In the two phylogenetic trees constructed by the neighbor-joining method, independent branches reflected that delimitation of the four new species was valid. Received: 17 June 1998 / Accepted: 7 August 1998  相似文献   

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Leaf protoplasts of two wild species, Solanum nigrum var. gigantea (S. ngr gig) and S. bulbocastanum Dun. (S. blb), were electrofused with leaf protoplasts of two diploid potato clones, H-8105 and ZEL-1136, respectively, in order to confer the late blight-resistance from the wild species to the cultivated potato. The S. ngr gig mesophyll (+) H-8105 mesophyll combination resulted in regenerants of mostly normal ngr phenotype. Two regenerants from this combination were proved to be true hybrids by RAPD analysis but they rooted poorely in vitro and did not survive the transfer to soil. The S. ngr gig (+) H-8105 fusion combination was also performed with H-8105 cell suspension derived protoplasts enabling an easy identification of interspecific fusants on basis of their intermediate morphology. From the S. ngr gig mesophyll (+) H-8105 cultured cell combination, many abnormal shoots were regenerated. The two lines which survived had normal ngr phenotype but the presence of tuberosum (tbr) genome in those regenerants was not confirmed by RAPD analysis. No plants with tbr phenotype were obtained from both of S. ngr gig (+) H-8105 combinations. On the contrary, when S. blb mesophyll protoplasts were electrofused with ZEL-1136 mesophyll protoplasts, all regenerated plants had tbr phenotype, indicating much lower morphogenetic potential of S. bulbocastanum in comparison with that of S. nigrum var. gigantea. However, the hybridity of those regenerants has not been confirmed by RAPD analysis with two different primers. The efficiency of the applied fusion procedure and analysis of the regenerants is discussed.  相似文献   

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A study of the skeletal remains of a Neandertal child from Kiik-Koba has brought to light some features that are typical of adult Neandertal individuals from Europe. Therefore, the ascertained differences in the proportions of the individual parts of upper and lower limbs, as well as a number of marked morphological features, such as the robusticity of ribs, typical Neandertal features of the scapula, curving of forearm bones, back-to-front curving of the femoral diaphysis, retroversion of the upper epiphysis of the tibia, and robusticity of long bones in the Neandertal individual at the age of infans I, may be regarded as phylogenetically ingrained ones. These may in their turn be considered diagnostic features, of importance in determining the phylogenetic classification of postcranial skeletal remains in the development of man.  相似文献   

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Summary Six newSalmonella types isolated in Ghana are described.S. volta, 11: 4: 1,z13, z28 was isolated from a swine;S.agona 4,12: fgs:—,S.wa, 16: b: 1,5S.technimani, 28: c: z6 andS.tafo, 1, 4 12, 27: z35: 1,7 were isolated from cattle;S.mampong, 13,22: z35: 1,6, was isolated from a lizzard.  相似文献   

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Protoplasts have been isolated from three tuber-bearing Solanum species, S. hjertingii, S. polyadenium and S. capsicibaccatum, that are sexually incompatible with S. tuberosum, but possess potentially useful characters. For isolating protoplasts from leaves of in vitro shoot cultures of S. hjertingii and S. capsicibaccatum growth was improved by including silver thiosulfate in the medium. However, for S. polyadenium, leaves of pot-grown plants were the best source for protoplasts. Following protoplast division and culture, plants were regenerated from protoplasts of each of the species. The pattern of chromosome variation in regenerants was similar to that observed for other diploid and tetraploid Solanum species. The results indicate that it should be possible to introduce the potentially useful germplasm from these wild species into somatic hybrids with S. tuberosum by protoplast fusion.Abbreviations STS silver thiosulfate - BAP benzylaminopurine - GA3 gibberellic acid - NAA naphthalene acetic acid - IAA indole-3-acetic acid  相似文献   

6.
Salmonella enterica subsp. enterica comprises a number of serovars, many of which pose an epidemiological threat to humans and are a worldwide cause of morbidity and mortality. Most reported food infection outbreaks involve the serovars Salmonella Enteritidis and Salmonella Typhimurium. Rapid identification to determine the primary sources of the bacterial contamination is important to the improvement of public health. In recent years, many DNA-based techniques have been applied to genotype Salmonella. Herein, we report the use of a manual TRS-PCR approach for the differentiation of the Salmonella enterica subspecies enterica serovars in a single-tube assay. One hundred seventy Salmonella strains were examined in this work. These consisted of serovars S. Enteritidis, S. Typhimurium, S. Infantis, S. Virchow, S. Hadar, S. Newport and S. Anatum. Five of the TRS-primers, N6(GTG)4, N6(CAC)4, N6(CGG)4, N6(CCG)4 and N6(CTG)4, perfectly distinguished the S. Enteritidis and S. Typhimurium serovars, and the N6(GTG)4 primer additionally grouped the other five frequently isolated serovars. In our opinion, the TRS-PCR methodology could be recommended for a quick and simple DNA-based test for inter-serovar discrimination of Salmonella strains.  相似文献   

7.
Plant regeneration from protoplasts is a prerequisite to the production of modified plants using somatic hybridization and transformation. Whole plant regeneration was achieved from protoplasts isolated from seedling cotyledons of Stylosanthes guianensis, S. macrocephala and S. scabra, three economically important species of this tropical forage legume genus. The effects of both protoplast density and protoplast culture method on cell division and plating efficiency are presented.Abbreviations BAP 6-benzylaminopurine - MES 2-(N-Morpholino) ethanesulfonic acid - MS Murashige and Skoog (1962) medium - NAA 1-naphthalenacetic acid On leave from: Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Brasil  相似文献   

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The mesophyll protoplasts were isolated from the Solanum tuberosum (S. tbr) clones of different ploidy level (4x Bzura cv., 2x H-8105, and 2x ZEL-1136) as well as from the wild species: S. bulbocastanum (S. blb, 2x) and two accessions of S. nigrum (S. ngr, 6x). Additionally, the protoplasts were isolated from the cell suspensions of Bzura cv. and H-8105 clone. The conditions of protoplast isolation as well as the media for their culturing and regeneration, were selected and optimized for the studied genotypes. For mesophyll protoplasts, the shooting calli were produced by all the cultured protoclones except that of S. bulbocastanum. The shoots excised from the protoplast-derived calli developed into whole plants in all the studied potato clones but only in one accession of S. nigrum, i.e. S. ngr var. gigantea. As for suspension-cell-derived protoplasts, only H-8105 clone produced the regenerative type of calli, though normal shoots could not be obtained. The regenerative capacity of the protoplasts isolated from leaves and cell suspensions is compared and discussed. We regret to report the death of M. Sc. Maria Borkowska after the completion of this work.  相似文献   

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The new species Semenovia pulvinata Pimenov & Kljuykov, S. dissectifolia Ukrainskaja & Kljuykov, S. imbricata Ukrainskaja & Kljuykov, and S. vachanica Ukrainskaja & Kljuykov from the mountains of Pamiro‐Alai, Tajikistan and adjacent Afghanistan, are described and illustrated. For the Chinese species S. millefolia (Diels) V. M.Vinogr. & Kamelin, also known as Heracleum millefolium Diels, the correct name is S. torilifolia (H. Boissieu) Pimenov comb. nov. based on Peucedanum torilifolium H. Boissieu. For another closely related Chinese species, Peucedanum malcolmii Hemsl. & H. Pearson, also belonging to Semenovia, the new combination S. malcolmii (Hemsl. & H. Pearson) Pimenov is proposed. Heracleum thomsonii C. B. Clarke var. glabrior C. B. Clarke from Kashmir (Ladakh) is regarded as an independent species of Semenovia, S. glabrior (C. B. Clarke) Pimenov & Kljuykov.  相似文献   

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Transfers and macerations of Alethopteris ambigua Lesquereux reveal it as axeromorphio plant. The papillose lower epidermis of each pinnule is sheltered by incurved pinnule margins, a bladelike extension of the midvein and by marginal hairs. Preservation is such that cellular outlines are discernible on all but the cuticles of the lower epidermis.  相似文献   

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We have previously reported the development of a technique utilizing nitrocellulose filters, which rapidly separates ribosomal protein-ribosomal RNA complexes from unbound protein. We have used this technique to obtain binding data for the association of proteins S4, S7, S8, S15, S17, and S20 with 16S RNA. With the exception of protein S17, the association behavior for each of these proteins exhibits a single binding site with a unique binding constant. The apparent association constants have been calculated and have been found to have a range from 1.6 x 10(6) M-1 for protein S7 to 7.1 x 10(7) M-1 for protein S17. The Scatchard plot for the protein S17 binding data is biphasic, suggesting that within the RNA population two different binding sites exist, each with a different apparent association constant.  相似文献   

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《Ibis》1946,88(2):243-245
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