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1.
Results obtained from crossing experiments betweenP. somniferum subsp.somniferum (2n = 22) and subsp.setigerum (2n = 44),P. glaucum (2n = 14) andP. gracile (2n = 14) and from the observation of meiotic chromosome pairing in the various hybrids obtained do not provide straightforward evidence for the hypothesis thatP. somniferum originated as a triploid hybrid between taxa similar toP. glaucum andP. gracile (Kadereit 1986a, b).—On the one hand, the pattern of crossability found reflects the closer similarity of subsp.somniferum toP. glaucum and of subsp.setigerum toP. gracile, which was interpreted as segregation of parental characters, and the high frequency of 2n = 28 chromosomes among F2-progeny from the hybrid subsp.somniferum × subsp.setigerum (2n = 33) might reveal n = 7 as the base number also ofP. somniferum. On the other hand, however, the general difficulty of obtaining hybrids, and the low incidence of bivalent formation in their meiosis, probably indicating a lack of chromosome homology between the different species, do not fit the above hypothesis.—These results are in marked contrast to the morphological similarity between the three species involved.  相似文献   

2.
Summary A gene library with DNA of Staphylococcus hyicus subsp. hyicus was established in S. carnosus by using the plasmid vector pCT20. Two clones of S. carnosus were isolated which were able to ferment d-ribose. The two hybrid plasmids (pRib 1) and (pRib 2) were isolated and characterized. They contained inserted DNA fragments of S. hyicus subsp. hyicus with sizes of 10.2 and 8.2 kb, respectively. d-Ribose uptake and enzyme activities were studied. All strains tested [S. hyicus subsp. hyicus, S. carnosus (wild type) and the two S. carnosus clones] possessed an inducible uptake system for d-ribose. S. hyicus subsp. hyicus possessed in addition enzyme activities of d-ribokinase and d-ribose-5-P isomerase. None of these enzyme activities could be detected in S. carnosus (wildtype). Only in the S. carnosus clones containing (pRib 1) or (pRib 2) could a d-ribokinase activity be demonstrated, indicating that the gene for d-ribokinase of S. hyicus subsp. hyicus was cloned in S. carnosus.Abbreviations bp base pairs - C-TLC cellulose-thin layer chromoatography - kb kilo base pairs - pRib 1 and 2 ribokinase activity conferring hybridplasmids - MBq megabequerel - wt wild type  相似文献   

3.
Crepis incarnata subsp.dinarica (G. Beck)Hayek is nowadays considered as a subspecies ofC. praemorsa (L.)Tausch. Comparative analyses of Feulgen karyotypes demonstrate great similarities, but remarkable differences in the presence and the distribution of the constitutive heterochromatin in the two taxa are detected by using the Giemsa differential staining technique (C-banding). This favours their specific distinctness.  相似文献   

4.
Quantitatively evaluated C-banded and conventional karyograms are presented for the related speciesScilla bifolia subsp.danubialis Speta,S. drunensis (Speta)Speta, andS. vindobonensis Speta. On the basis of banding patterns and karyotype structureS. bifolia subsp.danubialis (2n = 18, 2×) andS. drunensis (2n = 36, 4×) are quite similar, whileS. vindobonensis (2n = 18, 2×) is entirely different. There is a moderate degree of karyotypic variation withinS. bifolia subsp.danubialis andS. drunensis. However, inS. vindobonensis karyotypes and banding patterns are almost completely stable over a geographical range of about 500 km. The present results confirm the recent taxonomic separation ofS. vindobonensis fromS. bifolia, and suggest a considerable phylogenetic distance between these two diploid species. The results are discussed with reference to the morphological characters of the species and their geographical distribution.Evolution ofScilla and Related Genera, II.Dedicated to Univ.-Prof. Dr.Elisabeth Tschermak-Woess on the occasion of her 60th birthday.  相似文献   

5.
Population variability ofOphrys holosericea (Burm. f.)Greut. subsp.holosericea (=O. fuciflora Crantz subsp.fuciflora) from near Vienna (Austria), and of subsp.maxima (Fleischm.)Greut. andO. cornuta Steven with intermediates from the Dalmatian island Hvar (Yugoslavia) was analysed and illustrated by scatter diagrams. A hybrid origin of these intermediates is suggested. Aspects of hybridization betweenO. holosericea agg. andO. scolopax agg. are discussed.
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6.
The syntypes ofBromus madritensis var.delilei Boiss. comprise two different elements: specimens ofB. haussknechtii Boiss. and ofB. fasciculatus C. Presl s.l. By its lectotypification and on the basis of new morphological characters, the validation ofB. fasciculatus subsp.delilei (Boiss.)H. Scholz 1971 was substantiated. This subspecies represents the eastern marginal segregate of the south-Mediterranean species.B. fasciculatus var.alexandrinus Thell. is a minor variant of the typical subspecies.Dedicated to Prof.K. H. Rechinger on the occasion of his 80th birthday.  相似文献   

7.
TheThymus teucrioides Boiss. & Spruner aggregate is revised and the following new taxa, all from the alpine zone in the Greek mountains, are described:Th. leucospermus Hartvig from the calcareous mountains of Pindhos and Mt Parnassos in Sterea Ellas,Th. rechingeri Hartvig with the subsp.macrocalyx Hartvig from calcareous mountains in Sterea Ellas and N Peloponnissos, andTh. teucrioides subsp.alpinus Hartvig from the serpentine areas of N Pindhos. In the variableTh. teucrioides s. str. many characters have turned out to be markedly geographically correlated and many local populations can be distinguished by a particular combination of characters.Dedicated to Prof.K. H. Rechinger on the occasion of his 80th birthday.  相似文献   

8.
【目的】开发一种高效地从造礁石珊瑚中分离、培养共生虫黄藻的技术方法,为珊瑚共生虫黄藻藻种资源储备和生理功能研究积累基础。【方法】首先采用微孔滤网过滤法和密度梯度离心法从造礁石珊瑚组织中直接分离或富集共生虫黄藻细胞,然后用改良的L1培养基在96孔板上对所得细胞进行离体培养,最后进行单细胞分离、培养和(或)平板划线培养获得单克隆虫黄藻细胞系。对所得虫黄藻单克隆藻株进行聚合酶链式反应-限制性内切酶片段长度多态性(polymerase chainreaction-restrictionfragmentlengthpolymorphism,PCR-RFLP)分析,结合内转录间隔区2(internal transcribed spacer2,ITS2)和大亚基(large subunit,LSU)测序进行物种鉴定及系统发育分析。【结果】采用上述方法从涠洲岛的霜鹿角珊瑚(Acropora pruinose)和西沙群岛的丛生盔形珊瑚(Galaxea fascicularis)及柔枝鹿角珊瑚(Acropora tenuis)中分离、培养得到3个虫黄藻株系,编号分别为AP21C1、GF21D1和AT21A...  相似文献   

9.
WithinFestuca ovina agg. two hexaploid taxa:F. brevipila andF. carnuntina, and one tetraploid:F. eggleri, are described as new species.F. pseudovina Hack. exWiesb. is better treated asF. valesiaca Schleich. exGaudin subsp.parviflora (Hack.), comb. nova.
Drei neue Arten desFestuca ovina-Formenkreises (Poaceae) aus dem Osten Österreichs
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10.
Hypericum dogonbadanicum Assadi, a local species from theQuercus brandtii forests of the Zagros Mountains in south-western Iran, belongs to sect.Campylosporus (Spach)R. Keller and is most closely related to a Socotran endemic,H. socotranum Good subsp.smithii N. Robson. Despite the inclusion of these forests in the Irano-Turanian Element of the Iran flora byZohary (1963),H. dogonbadanicum appears to belong rather to the Mediterranean dwarf-shrub maquis type of community and therefore to be a member ofZohary's (1963) Mediterranean/Irano-Turanian group of Iranian species.—The key position of the Socotran endemics to the understanding of the inter-sectional relationships is discussed.Dedicated to Prof.K. H. Rechinger on the occasion of his 80th birthday.  相似文献   

11.
The chemical variation inLecanora epibryon andL. subimmersa, two species of theL. subfusca group, has been examined. In both species the chemical differences are correlated with geographical distribution, but not with morphological differences. As a consequence the chemotypes are recognized at subspecific level. InL. epibryon three chemical races are segregated according to the various chemosyndromes present. Subspeciesepibryon, containing atranorin and triterpenoids, occurs in the northern hemisphere and South America, while the other two subspecies occur only in the southern hemisphere. The subsp.broccha (Nyl.)Lumbsch, comb. nova, contains atranorin, the stictic acid and the 2,5,7-trichloro-3-O-methylnorlichexanthone chemosyndromes, while subsp.xanthophora Lumbsch, subsp. nova, is similar but lacks the stictic acid chemosyndrome. Two chemical races occur in the pantropical speciesL. subimmersa. While subsp.subimmersa contains atranorin and zeorin, subsp.ramboldii Lumbsch & Elix, subsp. nova, contains an additional ten chlorinated xanthones.L. impressa is reduced to synonymy toL. subimmersa.  相似文献   

12.
The central Sierran tetraploidArctostaphylos mewukka Merriam has been reported to be an allopolyploid originating from the diploid species,A. patula Greene and eitherA. viscida subsp.viscida Parry orA. viscida subsp.mariposa (Dudley)P. V. Wells, although without conclusive evidence. Morphometrics and the verification and determination of chromosome numbers were used to substantiate the evolutionary relationships among these species. A closely related species,Arctostaphylos truei Knight, was also examined using these methods to determine its separability fromA. mewukka. The morphometric analyses support a hypothesis for a polyphyletic origin ofA. mewukka from different races ofA. viscida andA. patula. The chromosomal data, although inclusive, also support this hypothesis. The data do not support the recognition ofA. truei as a taxonomic entity separate fromA. mewukka at the species level.  相似文献   

13.
We have used total genomic DNA as a probe to size-fractionated restriction enzyme digests of genomic DNA from a range ofTriticeae species from the generaLeymus Hochst.,Psathyrostachys Nevski, andHordeum L., and hybrids betweenHordeum andLeymus to investigate their taxonomic relationships. Genomic Southern hybridization was found to be an effective and simple way to assess the distribution and diversity of essentially species-specific and common, repetitive DNA sequences, and is hence especially useful in evolutionary studies. The DNA sequences ofH. vulgare seem to diverge substantially from those ofH. brachyantherum, H. lechleri, H. procerum, andH. depressum. The genome ofThinopyron bessarabicum shows little homology to those of theLeymus species investigated, confirming thatT. bessarabicum is not an ancestral genome inLeymus. Although the genomes ofLeymus andPsathyrostachys share substantial proportions of DNA sequences, they include divergent repeated sequences as well. Hybridization with a ribosomal DNA probe (pTa 71) showed that the coding regions containing structural genes encoding the 18 S, 5.8 S, and 26 S ribosomal RNA were conserved among the species investigated, whereas the intergenic spacer region was more variable, presenting different sizes of restriction fragments and enabling a classification of the species. The rye heterochromatin probe pSc 119.2 hybridized to DNA fromH. lechleri andT. bessarabicum, but not to DNA from the other species investigated.  相似文献   

14.
Four different strains ofLactobacillus delbrueckii subsp.bulgaricus (Ss1 and Yop12) andStreptococcus salivarius subsp.thermophilus (Ss2 and Yop9) were isolated from two different yogurt sources in Argentina. In medium containing different carbon sources: lactose, fructose, sucrose or glucose plus fructose, the growth of a mixed culture (Yop12+Ss2) shows stimulation ofS. thermophilus and inhibition ofL. bulgaricus with respect to pure cultures. Both microorganisms in mixed culture grew less well on glucose plus galactose. However, in medium with glucose or galactose, both microorganisms were stimulated.  相似文献   

15.
Silene thebana Orph. exBoiss. is transferred as a subspecies toS. fabaria (L.)Sm., resulting in the new combinationS. fabaria (L.)Sm. subsp.thebana (Orph. exBoiss.)Melzh. The chromosome count of 2n = 24 is recorded for the first time for this taxon.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday, 16th October 1986.  相似文献   

16.
Many groups of tropical cnidarians including scleractinian corals, octocorals, corallimorphs, and anemones contain the tertiary sulfonium compound dimethylsulfoniopropionate (DMSP). It is not known if the compound is synthesized by the animals, their microalgal symbionts, or derived through their diet. We determined the source of the DMSP in several species of tropical and temperate anemones using three approaches: (1) conducting comparative measurements of DMSP in aposymbiotic and zooxanthellate anemones of three species that harbor zooxanthellae, and similar measurements in one species that can harbor both zooxanthellae and zoochlorellae, (2) manipulating the presence or absence of zooxanthellae by inoculating juvenile aposymbiotic anemones (Aiptasia pallida) with their symbiont, Symbiodinium bermudense, and (3) manipulating the numbers of S. bermudense by growing aposymbiotic and zooxanthellate A. pallida in the light and the dark. DMSP was present in zooxanthellate anemones in concentrations of 3.4–15 μmol g−1 fresh mass (FM). In aposymbiotic Aiptasia spp. and Anthopleura elegantissima that lacked large numbers of zooxanthellae, concentrations ranged from being undetectable to 0.43 μmol g−1 FM. When aposymbiotic A. pallida were inoculated with zooxanthellae, concentrations of DMSP were an average of 4.24 μmol g−1 FM after 5 weeks; DMSP was undetectable in uninoculated control animals. Aposymbiotic anemones maintained in the light or the dark for 6 weeks contained no DMSP or zooxanthellae. Zooxanthellate anemones in the light contained five times as many zooxanthellae and approximately 7.5 times as much DMSP as zooxanthellate anemones maintained in the dark. Taken together, these data show that the zooxanthellae are the sole source of DMSP in A. pallida. The trends in DMSP concentrations in other species of zooxanthellate anemones suggest that this phenomenon is not limited to A. pallida but may be more generally true for other anemones or even other cnidarians hosting species of Symbiodinium. Communicated by Biology Editor Dr. Michael Lesser  相似文献   

17.
The Giemsa C-banding pattern of the chromosomes of the native self-pollinatedAegilops comosa subsp.comosa var.comosa was studied. Six of the seven chromosomes of the haploid genome were found to be polymorphic for C-banding patterns. Chromosome A had four variants, chromosome E three variants and each of the chromosomes B, D, and F two variants. Chromosomes E and G were polymorphic for arm length and arm ratio.This paper is part of the doctoral dissertation ofA. Georgiou.  相似文献   

18.
5 new taxa are described and illustrated; their position within the subgenus is discussed:T. hirta W. Till & L. Hromadnik,T. cotagaitensis L. Hromadnik,T. caliginosa W. Till, andT. gilliesii Baker subsp.polysticha W. Till & L. Hromadnik are members of a group includingT. myosura Grisebach exBaker,T. mandonii E. Morren exMez in DC.,T. retorta Grisebach exBaker em.Grisebach andT. andicola Gillies exBaker. T. brealitoensis L. Hromadnik is related toT. angulosa Mez in DC. but distinct and possibly of hybrid origin.
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19.
Strict sterility barriers where found between theScutellaria populations on Sicily and the Greek populations. The material from Samos is separated by a strict sterility barrier from the other Greek populations. In contrast, the populations on mainland Greece and adjacent islands are all ± interfertile. Three species are recognized,S. rubicunda Hornem., endemic to Sicily, andS. brevibracteata subsp.icarica, endemic to Samos and Ikaria. All other populations are referred toS. rupestris with eight subspecies, most of which are endemic to one island or to one mountain. Three new subspecies are described, viz. subsp.rechingeri and subsp.olympica, endemic to mt Vourinos and mt Olympus in North Greece, respectively, and subsp.caroli-henrici, native to the Malea peninsula of Peloponnisos. The phytogeographical connections and genetic differentiation within and between populations are discussed.Dedicated to Prof. DrK. H. Rechinger on the occasion of his 80th birthday.  相似文献   

20.
The taxon commonly namedHelleborus viridis in Lombardy (NW. Italy) differs from both, subsp.viridis and subsp.occidentalis, and is shown to fall within the variation range ofH. odorus subsp.laxus which has been reported so far for NE. Italy only. TrueH. viridis within Italy grows only in the Maritime Alps.  相似文献   

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