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1.
Roegneria grandis was hybridized withR. ciliaris var.japonensis (2n = 28, SSYY),Elymus caninus (2n = 28, SSHH), andPseudoroegneria spicata (2n = 28, SSSS). Chromosome pairing was studied in parents and hybrids. It is concluded from this study that: (i)R. grandis is an allotetraploid species and contains the basic genomes S and Y: (ii) a certain degree of homoeology exists between the S and Y genomes of the species studied. 相似文献
2.
Seven tetraploid species ofElymus, viz.E. sibiricus, E. caninus, E. gmelinii, E. semicostatus, E. caucasicus, E. parviglume, andE. longearistatus subsp.canaliculatus, representing five sections were studied morphologically and used in interspecific hybridizations. The aim was to investigate whether the present sectional delimitation of the genus was in agreement with genomic data and if there was a correlation between genome constitution and morphology. The study revealed: (i) further information on the genomic affinities between the different species, (ii) that there is no congruence between genome constitution of the species and current sectional delimitation, and (iii) that there is a correlation between genome constitution and morphology in the palea apex shape and in the size of cilia of the palea. 相似文献
3.
Bao-Rong Lu 《Plant Systematics and Evolution》1993,186(3-4):193-212
Hybridizations ofElymus nutans andE. jacquemontii were carried out with one species ofPseudoroegneria (S genome), and 20Elymus species, each containing either of the SH, SY, SYH, or SYW genomes. Chromosome configurations were analysed at metaphase I of the two target taxa and their interspecific hybrids. It is concluded that (i)E. nutans is an allohexaploid containing the SYH genomes, andE. jacquemontii is an allotetraploid having the SY genomes; (ii) the genomic affinity is associated with the geographic distance between the species studied; (iii) minor genomic structural rearrangements have occurred within the hexaploid taxon ofE. nutans. 相似文献
4.
Bao-Rong Lu 《Plant Systematics and Evolution》1993,187(1-4):191-211
Genomic relationships of 13 tetraploid species within the AsiaticElymus parviglumis group containing the SY genomes were assessed by analysing chromosome pairing at metaphase I of the parental species and their interspecific hybrids. Two major genomic subgroups among the tetraploids were identified from the cluster analysis of the averaged c-values, namely, theE. caucasicus subgroup (two species) and theE. parviglumis subgroup (11 species). The genomic affinity of theElymus species is associated with the interspecific geographic distance.After October 1, 1993 相似文献
5.
Kengyilia laxiflora (2n = 42) was cytogenetically studied with testersK. hirsuta (2n = 42, PPStStYY) andRoegneria kamoji (2n = 42, HHStStYY). Our data suggested thatK. laxiflora may possess a modified P genome, the P1. Its St and Y genomes may also contain some structural changes and are more closely related to the St and Y genomes ofK. hirsuta than to those ofR. kamoji. Kengyilia laxiflora is reproductively separated from bothK. hirsuta andR. kamoji. These results indicated thatK. laxiflora is a good species in the genusKengyilia. 相似文献
6.
Yong-Hong Zhou Chi Yen Jun-Liang Yang You-Liang Zheng 《Plant Systematics and Evolution》1999,217(3-4):215-220
Morphological and cytological studies of three tetraploidRoegneria species,R. tenuispica, R. pendulina andR. ciliaris, and their artificial hybrids were carried out.Roegneria tenuispica was morphologically similar toR. pendulina. The general appearance of the interspecific hybrids was intermediate between the parents. The hybrids showed comparatively high chromosome pairing at meiosis, but were completely or almost completely sterile. The results indicate that the three independent species share two basic genomes (StY) and thatR. tenuispica is more closely related toR. pendulina than toR. ciliaris. The genomes ofR. tenuispica could be designated as S
t
t
Yt. 相似文献
7.
Interspecific hybridizations were carried out between the two tetraploidsElymus caucasicus andE. longearistatus, and 23 tetraploids and hexaploids ofElymus containing SH, SY, SYH, and SYW genomes and representing various geographical regions. Meiotic pairing was studied in the two target species and their hybrids. It is concluded from this study that (i) interspecific hybridization is fairly easy to perform although strong reproductive barriers exist between the species; (ii)Elymus caucasicus andE. longearistatus are allotetraploids, and share the diverged SY genomes; (iii) the divergence of SY genomes is correlated with the geographic distance between theElymus spp. studied. 相似文献
8.
Roland von Bothmer Bao-Rong Lu Ib Linde-Laursen 《Plant Systematics and Evolution》1994,189(3-4):259-266
Crosses ofHordelymus europaeus (2n = 4x = 28) with four genera in theTriticeae were attempted. Adult hybrids were obtained in combinations withHordeum bogdanii (2x),Hordeum depressum (4x), andSecale cereale (2x). The meiotic pairing was very low in the hybrids withH. bogdanii andSecale cereale (0.12 and 0.30 chiasmata/cell, respectively), whereas high pairing (9.90 chiasmata/cell) was found in hybrids withH. depressum due to autosyndetic pairing ofH. depressum chromosomes. The chromosome complement ofHordelymus europaeus comprised 16 metacentrics, 8 submetacentrics, and 4 SAT-chromosomes. The Giemsa C-banding patterns of the chromosomes were characterized by small to minute bands at no preferential positions. It is hypothesized thatHordelymus europaeus may genomically be closest related toTaeniatherum andPsathyrostachys spp. 相似文献
9.
Based on 100 species representative of the four genera, we scored 290 herbarium specimens for a number of morphological characters. The data were subjected to canonical discriminant analysis using characters different from those in the identification key to these genera byBaum, Yen, andYang (1991). These characters collectively support the four groupsAgropyron, Kengyilia, Roegneria, andElymus as previously defined. The four groups are also supported by the linear discriminant function with an overall rate of 83% correct classification. Length of lemma awn was found to be an additional diagnostic character asAgropyron andKengyilia have lemma awns shorter than 5 mm, whereasRoegneria andElymus have longer lemma awns with very few exceptions. Length of glume awns is also a useful supplementary generic diagnostic.Agropyron andElymus have glume awns, whereas the majority of species ofKengyilia and more than half of the species ofRoegneria lack them. If a glume awn is present it is usually not longer than 1 mm. 相似文献
10.
Kengyilia habahenensis, spec. nova, from the Altai mountains, China, is described morphologically and cytologically. It has 2n = 42 chromosomes, and the genome formula PYS. 相似文献
11.
In order to investigate genomic relationships of tetraploidElymus species (all containing the SY genomes) among three morphological groups, i.e. theE. parviglumis, E. semicostatus, andE. tibeticus groups, interspecific hybridizations were carried out among representative species from the three groups. Chromosome associations at metaphase I were analysed in the interspecific hybrids, and genomic relationships of the species within and among the three groups were estimated. Hybridizations among species of the three groups were fairly easy to perform, but no general pattern for crossabilities among certain species or groups was obtained. All the hybrids were completely sterile. Meiotic pairing was moderately high, but ranges of chiasmata were observed in different hybrid combinations. There is no tendency for genomic affinities to be higher within groups than between the groups. Therefore, the meiotic data do not support the division of the SY-genome species into the three groups. However, there is a clear tendency that the differentiation of the SY genomes in the tetraploids is associated with the geographic distribution of the species. 相似文献
12.
The results of genome analysis of five hybrids, viz.Elymus patagonicus ×Hordeum procerum, E. patagonicus ×H. tetraploidum, E. angulatus ×H. jubatum, E. angulatus ×H. lechleri, andE. angulatus ×H. parodii, are reported. The genomic constitution ofHordeum tetraploidum andH. jubatum is best given as H1H1H2H2, ofH. lechleri andH. parodii as H1H1H2H2H4H4, ofH. procerum as H1H1H2H2H3H3, and ofElymus patagonicus andE. angulatus as SSH1H1H2H2. 相似文献
13.
The karyotypes ofElymus dentatus from Kashmir andE. glaucescens from Tierra del Fuego, both carrying genomesS andH, were investigated by C- and N-banding. Both taxa had 2n = 4x = 28. The karyotype ofE. dentatus was symmetrical with large chromosomes. It had 18 metacentric, four submetacentric and six satellited chromosomes. The karyotype ofE. glaucescens resembled that ofE. dentatus, but a satellited chromosome pair was replaced by a morphologically similar, non-satellited pair. The C-banding patterns of both species had from one to five conspicuous and a few inconspicuous bands per chromosome. N-banding differentiated the chromosomes of the constituent genomes by producing bands in theH genome only. TheS genomes of both species were similar with five metacentric and two satellited chromosomes having most conspicuous C-bands at telomeric and distal positions. They resembled theS genome of the genusPseudoroegneria. TheH genomes had four similar metacentric and two submetacentric chromosomes. The seventhH genome chromosome ofE. dentatus was satellited, that ofE. glaucescens nonsatellited, but otherwise morphologically similar. The C-bands were distributed at no preferential positions. TheH genome ofE. dentatus resembles theH genomes of some diploidHordeum taxa. 相似文献
14.
Genomic relationships between species of theElymus semicostatus group andElymus sensu lato (Poaceae)
Meiotic pairing behaviour in 19 interspecificElymus hybrids is reported and discussed. The hybrids were made between four species belonging to theE. semicostatus group of sect.Goulardia, viz.,E. semicostatus, E. abolinii, E. fedtschenkoi, andE. panormitanus (all 2n = 28), andElymus species of seven different sections, viz., sect.Clinelymiopsis:E. caucasicus (2n = 28); sect.Elymus:E. sibiricus (2n = 28); sect.Goulardia:E. caninus (2n = 28),E. trachycaulus (2n = 28), andE. tsukushiensis (2n = 42); sect.Hyalolepis:E. batalinii (2n = 42); sect.Hystrix:E. hystrix (2n = 28); sect.Macrolepis:E. canadensis (2n = 28); and sect.Turczaninovia:E. dahuricus (2n = 42). Chromosomal pairing at meiotic metaphase I indicated that the species of theE. semicostatus group are genomically closer to the tetraploidE. caucasicus and the hexaploid species, regardless of sectional origin, than to the other tetraploid species of sectionGoulardia. Highest meiotic pairing was found in hybrids involvingE. caucasicus, E. tsukushiensis, andE. dahuricus. The presence of pairing regulating genes inE. abolinii is suspected. 相似文献
15.
Intergeneric hybridizations were made betweenT. elongatum, and twoPsathyrostachys and fiveLeymus species. The seed set obtained onT. elongatum ×Leymus hybrids ranged from 5.65% to 20.00%, depending onLeymus species. The seed set obtained onT. elongatum ×Psathyrostachys hybrids ranged from 16.07% to 19.70%. Meiotic pairing at metaphase-I in JN diploid hybrids ofT. elongatum ×Psathyrostachys species revealed a very low level homology between the basic J and N genomes, and further demonstrated that the two genomes are quite diverged. Chromosome pairing in theT. elongatum ×Leymus secalinus hybrid averaged 15.19 univalents + 2.62 rod bivalents + 0.26 ring bivalents + 0.02 trivalents, suggesting that the partial Je chromosomes ofT. elongatum has homology withLeymus secalinus genomes.L. secalinus might have 3–4 chromosomes originating from Je genome. 相似文献
16.
Hordeum caespitosum
Scribner,H. jubatum L., andH. lechleri (Steudel)Schenck are very similar in appearance and therefore until recently were mostly not recognized as separate entities. The first two are tetraploid and natives to North America, but the second occurs naturally in eastern Siberia and has been introduced in Europe and South America and may become a cosmopolitan weed. The third is hexaploid and South American. This study analyses their morphological diversity by means of selected multivariate techniques in order to determine if there is justification to recognize them as three separate morphological species. Logistic discrimination, although based on a reduced set of characters, yielded the highest percent of correct assignments. A linear discriminant function is provided and validated by 100 bootstrap repeats. Canonical discriminant analysis indicated three groups. It is subsequently concluded that the three are separate morphological species. Although a linear discriminant function is given, a traditional identification key is provided based on the palea length and triad (the group of three spikelets at each rachis node) length. 相似文献
17.
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
18.
To evaluate the phylogenetic relationships of species in Pseudoroegneria and related genera, the nuclear ribosomal internal transcribed spacer (ITS) sequences were analyzed for eighteen Pseudoroegneria (St), two Elytrigia (E
e
St), two Douglasdeweya (StP), three Lophopyrum (E
e
and E
b
), three Agropyron (P), two Hordeum (H), two Australopyrum (W) and two Psathyrostachys (Ns) accessions. The main results were: (i) Pseudoroegneria gracillima, P. stipifolia, P. cognata and P. strigosa (2x) were in one clade, while P. libanotica, P. tauri and P. spicata (2x) were in the other clade, indicating there are the differentiations of St genome among diploid Pseudoroegneria species; (ii) P. geniculata ssp. scythica, P. geniculata ssp. pruinifera, Elytriga caespitosa and Et. caespitosa ssp. nodosa formed the E
e
St clade with 6-bp indel in ITS1 regions; and (iii) Douglasdeweya wangii, D. deweyi, Agropyron cristatum and A. puberulum comprised the P clade. It is unreasonable to treat P. geniculata ssp. scythica and P. geniculata ssp. pruinifera as the subspecies of P. geniculata, and they should be transferred to a new genus Trichopyrum, which consists of species with E
e
St genomes. It is also suggested that one of the diploid donor of D. wangii and D. deweyi is derived from Agropyron species, and it is reasonable to treat tetraploid species with StP genomes into Douglasdeweya. 相似文献
19.
Agropyron bessarabicum (2n = 14),A. rechingeri (2n = 28),A. junceiforme (2n = 28),A. elongatum (2n = 14),A. flaccidifolium (2n = 28) andA. scirpeum (2n = 28) were studied by isoelectric focusing of seed soluble proteins.—The protein profiles obtained from the six taxa showed a striking degree of similarity; typically they consist of 40 bands. No qualitative but only quantitative differences (in the intensity of some bands) were found.—Combined with the cytological information available these protein data indicate that the two polyploid complexes must be placed in the recently erected genusThinopyrum with the genome designations:T. bessarabicum Jj1 Jj1,T. sartorii (=A. rechingeri) Jj1 Jj1 Jj3 Jj3,T. junceiforme Jj1 Jj1 Jj2 Jj2,T. elongatum Je1 Je1,T. flaccidifolium Je1 Je1 Je1 Je1 andT. scirpeum Je1 Je1 Je2 Je2. 相似文献
20.
Intergeneric hybridization betweenElymus anthosachnoides (2n = 28,SSYY) andPsathyrostachys huashanica (2n = 14,NN) was performed. Three hybrid plants, obtained via embryo rescue, were intermediate between the parents in morphology and developed vigorously, but were completely sterile. The mean chromosome configuration was 19.48 I + 0.76 II per cell in the hybrids at meiotic metaphase I. This result indicates thatE. anthosachnoides andP. huashanica are distantly related and that there is little or no homoeology betweenN (P. huashanica) andS orY (E. anthosachnoides) genomes. 相似文献