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1.
C-banding patterns and polymorphisms were analyzed in several accessions of the diploidAegilops speciesAe. uniaristata, Ae. mutica, andAe. comosa subsp.comosa and subsp.heldreichii, and standard karyotypes of these species were established. Variation in C-band size and location was observed between different accessions, but did not prevent chromosome identification. One accession ofAe. uniaristata was homozygous for whole-arm translocations involving chromosomes 1N and 5N. The homoeologous relationships of these chromosomes were established by comparison of chromosome morphologies and C-banding patterns to other diploidAegilops species with known chromosome homoeology. In addition, in situ hybridization analysis with a 5S rDNA probe was used to identify homoeologous groups 1 and 5 chromosomes. The present analysis permitted the assignment of allAe. mutica, comosa subsp.comosa, andAe. comosa subsp.heldreichii chromosomes, and three of the sevenAe. uniaristata chromosomes according to their homoeologous groups. The data presented will be useful analyzing genome differentiation in polyploidAegilops species.  相似文献   

2.
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   

3.
Summary C-banding patterns were analysed in 19 different accessions of Aegilops caudata (= Ae. markgrafii, = Triticum dichasians) (2n = 14, genomically CC) from Turkey, Greece and the USSR, and a generalized C-banded karyotype was established. Chromosome specific C-bands are present in all C-genome chromosomes, allowing the identification of each of the seven chromosome pairs. While only minor variations in the C-banding pattern was observed within the accessions, a large amount of polymorphic variation was found between different accessions. C-banding analysis was carried out to identify Ae. caudata chromosomes in the amphiploid Triticum aestivum cv Alcedo — Ae. caudata and in six derived chromosome addition lines. The results show that the amphiploid carries the complete Ae. Caudate chromosome complement and that the addition lines I, II, III, IV, V and VIII carry the Ae. caudata chromosome pairs B, C, D, F, E and G, respectively. One of the two SAT chromosome pairs (A) is missing from the set. C-banding patterns of the added Ae. caudata chromosomes are identical to those present in the ancestor species, indicating that these chromosomes are not structurally rearranged. The results are discussed with respect to the homoeologous relationships of the Ae. caudata chromosomes.  相似文献   

4.
Polyacrylamide gel electrophoresis of aspartate aminotransferase (AAT, EC 2.6.1.1) and alcohol dehydrogenase (ADH, EC 1.1.1.1) isoenzymes reveals intraspecific differentiation ofAegilops tauschii Coss. (=Ae. squarrosa auct., non L.) into two groups of biotypes which essentially correspond to its two morphological subspecies, subsp.tauschii and subsp.strangulata (Eig)Tzvel. Subsp.tauschii which is characterized by a slower electromorph of AAT-B and a faster electromorph of ADH-A is identified as the contributor of its D genome to the tetraploidAe. cylindrica Host and the hexaploidAe. crassa Boiss. subsp.crassa. Subsp.strangulata, being distinguished by a faster electromorph of AAT-B and a slower electromorph of ADH-A, has contributed the D genome to the hexaploid bread wheats (Triticum aestivum L. emend.Thell.), the tetraploidsAe. crassa subsp.macrathera (Boiss.)Zhuk. andAe. ventricosa Tausch, and the hexaploidAe. juvenalis (Thell.)Eig.Aegilops comosa Sibth. etSm. s. lat. is questioned as the contributor of the M genome toAe. crassa. Furthermore, the S genome diploidsAe. bicornis (Forsk.)Jaub. & Spach,Ae. longissima Schweinf. & Muschl. s. lat. andAe. searsii Feldman & Kislev are all considered unsuitable as the wheat B genome donors on the basis of the AAT isoenzyme data.  相似文献   

5.
Summary Putative D genome donors for Aegilops cylindrica (2n = 28, CCDD) and Triticum aestivum (2n = 42, AABBDD) were studied with the isoelectric focusing patterns of esterase isozymes. 103 strains of Ae. cylindrica were uniform in their isozyme pattern. 30 strains of the putative parent, Ae. caudata, showed no zymogram variation, whereas the other parent, Ae. squarrosa, comprised 3 phenotypes. Natural Ae. cylindrica had an isozyme pattern which corresponded to a mixture of esterases from Ae. caudata and type 3 Ae. squarrosa. Therefore, it is concluded that the D genome donor of Ae. cylindrica is derived from type 3 Ae. squarrosa. These results suggest that Ae. cylindrica originated with a single amphiploidy event, and the C and D genomes have remained remarkably constant regarding esterase isozyme composition.On the other hand, T. aestivum comprised three zymogram phenotypes. These phenotypes contain bands which can be ascribed to the D genome of type 2 Ae. squarrosa. These results suggest that the D genome of Ae. cylindrica differs from that of T. aestivum. Evolution of the AB and D genomes of T. aestivum is indicated by the zymogram polymorphism. The origin of Ae. cylindrica is possibly more recent than that of T. aestivum.Contribution No. 433 of the Laboratory of Genetics, Faculty of Agriculture, Kyoto University  相似文献   

6.
Summary Banding patterns of esterase isozymes in Aegilops triuncialis (2n = 28, genome formula CuCuCC) and its putative parental species, Ae. umbellulata (2n = 14, CuCu) and Ae. caudata (2n = 14, CC), were studied by the gel isoelectric focusing method using pH 6–8 carrier ampholite. Zymogram phenotypes of both parents were quite uniform. Seven zymogram phenotypes (designated as phenotypes 1 to 7) were found among the 260 strains of Ae. triuncialis examined. Of these phenotypes, phenotype 1 was identical to the zymogram phenotype produced by the ancestral species, Ae. umbellulata, and bands considered to have been derived from Ae. caudata were absent in this phenotype. Phenotype 3 had all bands of both parents. The other phenotypes differed greatly from phenotype 3. Therefore, phenotype 3 was considered to be most primitive of the 7 types, and the Ae. triuncialis strains which showed phenotype 3 to be the most primitive of the strains examined. If Ae. triuncialis originated as a hybrid between Ae. umbellulata and Ae. caudata, the zymogram phenotype must have been phenotype 3, in which the isozymes of both parental species are present. Whether the phenotypes other than type 3 were due to introgressive hybridization could not be verified, but they were considered in this article to be a consequence of a rearrangement of chromosomes.Contribution from the Laboratory of Genetics, Faculty of Agriculture, Kyoto University No. 432  相似文献   

7.
The genetic frequencies of 9 isozyme loci have been estimated in 23 samples of 4 species ofSecale by means of starch gel electrophoresis. The populations ofS. silvestre andS. vavilovii were monomorphic and uniform within each species, those ofS. montanum andS. cereale were polymorphic for most of the isozyme loci. On the basis of isozyme patterns as well as allelic and genotypic frequencies of isozyme loci,S. silvestre can be distinguished fromS. vavilovii, and both fromS. cereale andS. montanum; but there is no clear differentiation between the two latter species. Clusters constructed from genetic distances separateS. silvestre andS. vavilovii, whereasS. cereale andS. montanum were grouped together. The isozymatic data presented here, along with cytogenetic and life habit data, agree with the generally admitted existence of 4 species inSecale, and support the relationships suggested byKhush & Stebbins (1961).  相似文献   

8.
The D genome cluster includes six allopolyploidAegilops species having as pivotal genome that ofAegilops squarrosa. Alpha-gliadins, endosperm proteins coded by multigenic families, have been analyzed in the D genome species cluster and in their putative progenitors. They can be present or weakly expressed when analyzed in acid polyacrylamide gel electrophoresis. Molecular analysis has shown the possibility to distinguish subsp.strangulata from subsp.eusquarrosa and to confirm the presence ofAe. caudata and ofAe. umbellulata in the polyploidsAe. cylindrica andAe. juvenalis, respectively. Finally, introgression fromAe. longissima orAe. searsii in tetraploid and hexaploidAe. crassa, Ae. juvenalis, andAe. vavilovii is supposed.  相似文献   

9.
A native population ofAegilops cylindrica was encountered for the first time in Greece in 1980 (near Kastoria, NW. Greece), completely isolated and at a great distance from its main distribution area. There are morphological and chromosomal, but no protein and esterase pattern differences from otherAe. cylindrica populations. This justifies the recognition of a new variety: var.kastorianum. Our comparative and karyotypic observations support the view thatAe. caudata var.polyathera and not var.caudata (typica) is the possible donor of genome C of the new variety.  相似文献   

10.
RAPD analysis was carried out to study the genetic variation and phylogenetic relationships of polyploid Aegilops species, which contain the D genome as a component of the alloploid genome, and diploid Aegilops tauschii, which is a putative donor of the D genome for common wheat. In total, 74 accessions of six D-genome Aegilops species were examined. The highest intraspecific variation (0.03–0.21) was observed for Ae. tauschii. Intraspecific distances between accessions ranged 0.007–0.067 in Ae. cylindrica, 0.017–0.047 in Ae. vavilovii, and 0–0.053 inAe. juvenalis.Likewise, Ae. ventricosaand Ae. crassa showed low intraspecific polymorphism. The among-accession difference in alloploidAe. ventricosa (genome DvNv) was similar to that of one parental species, Ae. uniaristata (N), and substantially lower than in the other parent, Ae. tauschii (D). The among-accession difference in Ae. cylindrica(CcDc) was considerably lower than in either parent, Ae. tauschii (D) orAe. caudata (C). With the exception of Ae. cylindrica, all D-genome species—Ae. tauschii (D),Ae. ventricosa (DvNv), Ae. crassa (XcrDcr1 and XcrDcr1Dcr2), Ae. juvenalis (XjDjUj), andAe. vavilovii (XvaDvaSva)—formed a single polymorphic cluster, which was distinct from clusters of other species. The only exception, Ae. cylindrica(CcDc), did not group with the other D-genome species, but clustered withAe. caudata (C), a donor of the C genome. The cluster of these two species was clearly distinct from the cluster of the other D-genome species and close to a cluster of Ae. umbellulata (genome U) and Ae. ovata (genome UgMg). Thus, RAPD analysis for the first time was used to estimate and to compare the interpopulation polymorphism and to establish the phylogenetic relationships of all diploid and alloploid D-genome Aegilops species.  相似文献   

11.
Slab gel electrophoresis techniques have been applied to the study of isozyme and kernel protein patterns in 20 accessions ofHordeum chilense and related species in order to elucidate their phylogenetic relationships. On the basis of our results we can conclude that: (1) Conventional classification based on morphological characters does not totally agree with biochemical data. (2) Sectt.Anisolepis andCritesion seem to be clearly differentiated. (3) The accessions classified asH. compressum present biochemical phenotypes quite different from the rest of the species. (4)H. stenostachys, H. muticum andH. chilense constitute a group of variable species with many biochemical similarities and close phylogenetic relationships. (5) The evolutionary pattern of these American species seems to follow a model of reticulate evolution.  相似文献   

12.
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   

13.
Twenty enzyme loci were examined in the diploid species ofTriticum andAegilops for allelic variation by starch gel electrophoresis. SectionSitopsis, including the five species,Ae. speltoides, Ae. lingissima, Ae. sharonensis, Ae. bicornis andAe. searsii form a close subgroup withAe. speltoides slightly removed from the others.T. monococcum s. lat., was found to be closest to the species of theSitopsis group.Ae. comosa, Ae. umbellulata andAe. uniaristata form a second subgroup withAe. caudata most closely related to these species.Ae. squarrosa appears almost equally related to all of the species, showing no special affinity for any one species group. Nineteen out of twenty loci examined were polymorphic with a mean of 6.7 alleles per locus. Species could be, for most loci, characterized by the presence of predominant alleles. A conspicious genetic characteristic ofTriticum-Aegilops is the sharing of these predominant alleles between species. Within species variation is characterized by a diffuse distribution of secondary alleles.  相似文献   

14.
Saponaria stenopetala sp.n. in Eastern Afghanistan is close toS. pachyphylla Rech. f. andS. subrosularis Rech. f.—The nearest allies ofS. makranica sp.n. from Western Pakistan and Southeastern Iran areS. kermanensis Bornm. andS. floribunda (Kar. & Kir.)Boiss.
Flora Iranicae praecursores 36–37. — Praecursores praecurrentes in Pl. Syst. Evol.139, 313–317 (1982).  相似文献   

15.
Morphological differentiation of diploid accessions ofHordeum marinum Huds. s.l. into two varieties, var.marinum and var.fouilladei (Rouy)Nevski is associated with isoenzyme differentiation. The tetraploid form ofH. marinum s.l. exhibited fixed heterozygosity of several heterozymes with one homoeozyme shared with var.fouilladei and the second homoeozyme not found in the two diploids. It also differed from both diploids in the mobility of glucose-6-phosphate dehydrogenase. All three taxa differed in morphs of EST-A. It is concluded that the tetraploid is an allopolyploid with one genome closely related to the diploid var.fouilladei and with the second genome divergent from those of both diploids by genes for unique morphs of eight homoeozymes. On the basis of the isoenzyme data, three phylogenetic sibling species—H. marinum Huds. s.str. (2x),H. geniculatum All. s.str. (= var.fouilladei, 2x), andH. caudatum Jaaska, spec. nova (4x), are proposed within theH. marinum s.l. complex and a key is given.  相似文献   

16.
The genus Aegilops has an important potential utilization in wheat improvement because of its resistance to different biotic and abiotic stresses and close relation with the cultivated wheat. Therefore, a better knowledge of the eco-geographical distribution of Aegilops species and their collection and conservation are required. A total of 297 Aegilops accessions representing nine (five tetraploid and four diploid) species were collected in different regions of Bulgaria, and the ecological characteristics of the 154 explored sites were recorded. The distribution of the diploid species (Ae. caudata L., Ae. speltoides Tausch, Ae. umbellulata Zhuk. and Ae. comosa Sibth. and Sm.) was limited to specific environments in south-central Bulgaria. Tetraploid species were present in harsher environments than diploid species and showed wider adaptation and distribution. Species–environment relationships were analysed by considering the worldwide distribution of the species and their physiological resistance to abiotic stress. Aegilops cylindrica Host was more frequently found in northern Bulgaria and at high altitudes. Its distribution was closely related to its tolerance to low temperatures. Aegilops geniculata Roth and Ae. neglecta Req. ex Bertol. were absent in the north of Bulgaria, but widely distributed in low rainfall areas. Aegilops neglecta, more frost resistant than Ae. geniculata, was present at higher altitude. Aegilops biuncialis Vis. and Ae. triuncialis L. showed adaptation to a wide range of climatic conditions. The study of Aegilops species ecology and distribution in Bulgaria provided useful information for the future collection and for the genetic resource management in this region.  相似文献   

17.
5 new taxa ofHabenaria, namelyH. bougainvillae, H. elongata R. Br. var.leptophylla, H. ensigera, H. rechingeri andH. trichoglossa, are described and illustrated, with reference to affinities to related Australian and Indo-malayan species. The occurrence in New Guinea of severalHabenaria spp. typical for a savanna-like vegetation, led to look more thoroughly at these taxa:H. elongata R. Br. andH. ochroleuca R. Br., considered so far to be endemic in Northern Australia, andH. khasiana Hook. f., hitherto only known from southeastern Asia.Studies in the subtribeHabenariinae Bentham (Orchidaceae), 2.—Part 1: Candollea34, 357 (1979).Dedicated to Hofrat Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. — On April 30, in the year 1927, the author and his brotherOtto Renz metKarl Heinz Rechinger on a small steam-boat in a stormy Aegaen Sea, travelling from Piraeus to the Northern Sporades Islands:Karl Heinz with destination to Chelidromia, the author andO. Renz to Skopelos. By this lucky chance a lasting friendship began.  相似文献   

18.
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   

19.
Genetic variation within and the relationship betweenStellaria longipes Goldie andS. longifolia Muhl. were studied. Ten enzyme systems were assessed in eight natural populations ofS. longipes (25 loci) and three ofS. longifolia (20 loci) using starch and polyacrylamide gel electrophoresis. Patterns of population differentiation corresponded to geographic distance. There was no evidence that polyploidS. longipes had greater electrophoretic variability than diploidS. longipes. The isozyme data confirmed extensive population differentiation in these species and, within that context, a relatively close relationship betweenS. longipes andS. longifolia. It was postulated that diploids of these two species might be the progenitors of tetraploidS. longipes.  相似文献   

20.
The diagnostic characters alleged byEttl (1981) andEttl &Komarek (1982) to distinguish the ClassesChlamydophyceae andChlorophyceae are discussed. The recognition of these classes ignores ultrastructural evidence of the close phylogenetic relationships of their members and produces an artificial redistribution of orders, families, and genera that can only lead to confusion in the taxonomy of the green algae. Suggestions for a more natural classification are made.  相似文献   

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