HYBRIDIZATION BETWEEN ANNUAL AND PERENNIAL DIPLOID SPECIES OF HELIANTHUS

Hybrid characteristics, fertility and meiosis are described for the first interspecific hybrids to be obtained from crosses of the two perennial species (2n = 34) Helianthus giganteus and H. maximiliani with the annual species H. annuus (2n = 34). A single, highly pollen-sterile hybrid, H. giganteus × H. annuus cv. Krasnodarets, had abnormal meiosis with meiocytes containing univalents and multivalents. It was completely female sterile. The three H. giganteus × wild H. annus and four H. maximiliani × wild H. annuus hybrids had less than 5% normal pollen, and meiotic behavior suggested the presence of at least three interchanges and a paracentric inversion. Small quantities of seed were obtained by backcrossing with H. annuus cv. Saturn.

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Evidence for genetic suppression of heterogenetic chromosome pairing in polyploidy species of Solanum, sect. Petota

Canadian Journal of Genetics and Cytology ◽

10.1139/g83-080 ◽

1983 ◽

Vol 25 (5) ◽

pp. 530-539 ◽

Cited By ~ 26

Author(s):

Jan Dvořák

Keyword(s):

Chromosome Pairing ◽

Interspecific Hybrids ◽

Diploid Species ◽

Diploid Hybrid ◽

Polyploid Species ◽

Chromosome Differentiation ◽

Genetic Suppression ◽

Solanum Sect ◽

Paradoxical Results

Data on chromosome pairing in haploids and interspecific hybrids of Solanum, sect. Petota reported in the literature were used to determine whether the diploidlike chromosome pairing that occurs in some of the polyploid species of the section is regulated by the genotype or brought about by some other mechanism. The following trends emerged from these data. Most of the polyploid × polyploid hybrids had high numbers of univalents, which seemed to indicate that the polyploid species were constructed from diverse genomes. Haploids, except for those derived from S. tuberosum, had incomplete chromosome pairing. All hybrids from diploid × diploid crosses had more or less regular chromosome pairing, which suggested that all investigated diploid species have the same genome. Likewise, hybrids from polyploid × diploid crosses had high levels of chromosome pairing. These paradoxical results are best explained if it is assumed that (i) the genotypes of most polyploid species, but not those of the diploid species, suppress heterogenetic pairing, (ii) that nonstructural chromosome differentiation is present among the genomes of both diploid and polyploid species, and (iii) the presence of the genome of a diploid species in a polyploid × diploid hybrid results in promotion of heterogenetic pairing. It is, therefore, concluded that heterogenetic pairing in most of the polyploid species is genetically suppressed.

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Evidence for the presence of an intercontinental genome in the Australian hexaploid alliance of Hibiscus Sect. Furcaria

Australian Journal of Botany ◽

10.1071/bt9800369 ◽

1980 ◽

Vol 28 (3) ◽

pp. 369 ◽

Cited By ~ 2

Author(s):

MY Menzel ◽

DW Martin

Keyword(s):

Sri Lanka ◽

South America ◽

Interspecific Hybrids ◽

New World ◽

Hawaiian Islands ◽

Diploid Species ◽

Australian Species ◽

Data Support ◽

North And South America ◽

North And South

Genomes of the G group in Hibiscus sect. Furcaria have been found previously in one African diploid species and in various ailoploid combinations in Africa, India and Sri Lanka, North and South America and the Hawaiian Islands. Study of 11 interspecific hybrids between the Australian species H. heterophyllus and H. splendens and G-genome testers indicates that genomes somewhat related to the G group are present in the Australian allohexaploid alliance. These genomes are designated G′. Several of the intercontinental hybrids studied were weak, inviable or morphologically abnormal. The data support the interpretation that the genomes of the Australian alliance have diverged more from African and New World genomes than the latter two have from each other.

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Oligo-painting and GISH reveal meiotic chromosome biases and increased meiotic stability in synthetic allotetraploid Cucumis ×hytivus with dysploid parental karyotypes

BMC Plant Biology ◽

10.1186/s12870-019-2060-z ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Qinzheng Zhao ◽

Yunzhu Wang ◽

Yunfei Bi ◽

Yufei Zhai ◽

Xiaqing Yu ◽

...

Keyword(s):

Interspecific Hybridization ◽

Interspecific Hybrids ◽

Chromosome Doubling ◽

Meiotic Chromosome ◽

Genomic In Situ Hybridization ◽

Meiotic Behavior ◽

Cytological Evidence ◽

Meiotic Stability ◽

Inbred Family

Abstract Background Meiosis of newly formed allopolyploids frequently encounter perturbations induced by the merging of divergent and hybridizable genomes. However, to date, the meiotic properties of allopolyploids with dysploid parental karyotypes have not been studied in detail. The allotetraploid Cucumis ×hytivus (HHCC, 2n = 38) was obtained from interspecific hybridization between C. sativus (CC, 2n = 14) and C. hystrix (HH, 2n = 24) followed by chromosome doubling. The results of this study thus offer an excellent opportunity to explore the meiotic properties of allopolyploids with dysploid parental karyotypes. Results In this report, we describe the meiotic properties of five chromosomes (C5, C7, H1, H9 and H10) and two genomes in interspecific hybrids and C. ×hytivus (the 4th and 14th inbred family) through oligo-painting and genomic in situ hybridization (GISH). We show that 1) only two translocations carrying C5-oligo signals were detected on the chromosomes C2 and C4 of one 14th individual by the karyotyping of eight 4th and 36 14th plants based on C5- and C7-oligo painting, and possible cytological evidence was observed in meiosis of the 4th generation; 2) individual chromosome have biases for homoeologous pairing and univalent formation in F1 hybrids and allotetraploids; 3) extensive H-chromosome autosyndetic pairings (e.g., H-H, 25.5% PMCs) were observed in interspecific F1 hybrid, whereas no C-chromosome autosyndetic pairings were observed (e.g. C-C); 4) the meiotic properties of two subgenomes have significant biases in allotetraploids: H-subgenome exhibits higher univalent and chromosome lagging frequencies than C-subgenome; and 5) increased meiotic stability in the S14 generation compared with the S4 generation, including synchronous meiosis behavior, reduced incidents of univalent and chromosome lagging. Conclusions These results suggest that the meiotic behavior of two subgenomes has dramatic biases in response to interspecific hybridization and allopolyploidization, and the meiotic behavior harmony of subgenomes is a key subject of meiosis evolution in C. ×hytivus. This study helps to elucidate the meiotic properties and evolution of nascent allopolyploids with the dysploid parental karyotypes.

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Cytological and molecular analysis of annual species of the genus Medicago

Canadian Journal of Botany ◽

10.1139/b96-036 ◽

1996 ◽

Vol 74 (2) ◽

pp. 299-307 ◽

Cited By ~ 6

Author(s):

A. Mariani ◽

F. Pupilli ◽

O. Calderini

Keyword(s):

Chromosome Number ◽

Molecular Analysis ◽

Genetic Relationship ◽

Diploid Species ◽

Rflp Analysis ◽

Molecular Study ◽

Annual Species ◽

Genetic Affinity ◽

Karyological Analysis ◽

Medicago Rugosa

Medicago rugosa and M. scutellata, two annual species of the genus Medicago, have aroused considerable interest because they carry useful traits that could be introduced into alfalfa and have a chromosome number (2n = 30) that is quite unusual in Medicago. A cytogenetic and molecular study was undertaken to investigate the annual diploid species with 2n = 16 and 2n = 14 that seem to be the most closely related to M. rugosa and M. scutellata, with the aim of characterizing these diploid species and determining their genetic relationship with the species with 2n = 30. Karyological analysis established that some of the diploid species investigated were more similar than the others to both M. rugosa and M. scutellata (as in the case of M. intertexta, M. rotata, and M. polymorpha) or at least to one of those two species (as was the case with M. doliata, M. muricoleptis, and M. murex). RFLP analysis identified four species, namely M. intertexta and M. muricoleptis with 2n = 16, and M. polymorpha and M. murex with 2n = 14, as having the highest degree of genetic affinity with the two species with 30 chromosomes. These findings suggest the possibility of identifying the ancestors of M. rugosa and M. scutellata among those four species and therefore of verifying the probable allopolyploid origin of the two species in question. Keywords: Medicago, annual species, karyotypes, RFLPs.

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Cytogenetics of Hybrids Among Perennial Species of Glycine Subgenus Glycine

Australian Journal of Botany ◽

10.1071/bt9790713 ◽

1979 ◽

Vol 27 (6) ◽

pp. 713 ◽

Cited By ~ 27

Author(s):

E Putievsky ◽

P Broue

Keyword(s):

Cytogenetic Analysis ◽

Diploid Species ◽

The Other ◽

F1 Hybrids ◽

Pollen Stainability ◽

Perennial Species ◽

Tetraploid Form ◽

Other Hand ◽

Self Fertilization

A cytogenetic analysis based on F1 hybrids of some of the perennial species of Glycine subgenus Glycine Verdc. shows that G. clandestina and G. canescens are closely related and further, that either one of these diploid species could have provided one genome for the tetraploid form of G. tomentella. On the other hand, it appears that G. falcata and G. tabacina are distinctive species which are not closely related to the other three species. The tetraploid form of G. tomentella is genetically heterogeneous and crosses between certain types yield F1s with low pollen stainability which fail to set seed under conditions of self-fertilization.

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Meiotic analysis in induced tetraploids of Brachiaria decumbens Stapf

Cropp Breeding and Applied Biotechnology ◽

10.1590/s1984-70332011000100006 ◽

2011 ◽

Vol 11 (1) ◽

pp. 43-49 ◽

Cited By ~ 9

Author(s):

Carine Simioni ◽

Cacilda Borges do Valle

Keyword(s):

Chromosome Segregation ◽

Pollen Fertility ◽

Interspecific Hybrids ◽

Somatic Chromosome ◽

Breeding Program ◽

Meiotic Behavior ◽

Brachiaria Decumbens ◽

Meiotic Analysis ◽

Chromosome Duplication

The meiotic behavior of three tetraploid plants (2n=4x=36) originated from somatic chromosome duplication of sexually reproducing diploid plants of Brachiaria decumbens was evaluated. All the analyzed plants presented abnormalities related to polyploidy, such as irregular chromosome segregation, leading to precocious chromosome migration to the poles and micronuclei during both meiotic divisions. However, the abnormalities observed did not compromise the meiotic products which were characterized by regular tetrads and satisfactory pollen fertility varying from 61.36 to 64.86%. Chromosomes paired mostly as bivalents in diakinesis but univalents to tetravalents were also observed. These studies contributed to the choice of compatible fertile sexual genitors to be crossed to natural tetraploid apomicts in the B. decumbens by identifying abnormalities and verifying pollen fertility. Intraespecific crosses should reduce sterility in the hybrids produced in the breeding program of Brachiaria, a problem observed with the interspecific hybrids produced so far.

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Aegilops × Secale hybrids: the production and cytology of diploid hybrids

Genetics Research ◽

10.1017/s0016672300012003 ◽

1971 ◽

Vol 17 (1) ◽

pp. 17-31 ◽

Cited By ~ 10

Author(s):

B. N. Majisu ◽

J. K. Jones

Keyword(s):

Embryo Culture ◽

Interspecific Hybrids ◽

Diploid Species ◽

Genetic Mechanism ◽

Genetic Incompatibility ◽

Homologous Chromosomes ◽

Homoeologous Chromosomes

SUMMARYHybrids between four diploid species of Aegilops and species of Secale were obtained by using embryo culture. There was a marked incompatibility in the crosses between Secale species and each of the four species in Section Sitopsis of Aegilops and Ae. mutica. It is suggested that this genetic incompatibility with Secale species is an additional similarity between these species of Aegilops and the diploid species of Triticum.Most chromosomes of Aegilops (A) and Secale (S) are univalent during meta-anaphase of meiosis in these hybrids, but some appeared to associate and others to pair as apparently normal chiasmate bivalents. Analysis of non-chiasmate and chiasmate associations showed that the frequencies of autosyndetic (AA and SS) and allosyndetic (AS) associations fitted the 3AA: 7AS: 3SS ratio expected if association and pairing is at random. Any deviations from random involved a deficiency rather than an excess of Aegilops-Secale pairing. There is no evidence that the chromosomes of Secale are homologous with those of Ae. caudata, Ae. comosa and Ae. umbel-lulata, and it is suggested that the genome of Secale species does not show any homology with the genomes of the genera Aegilops. This does not preclude the presence of homologous segments. It is suggested that the possibility of random association of chromosomes should be considered when occasional pairing in interspecific hybrids is analysed, and that identification of chromosomes and recognition of chiasmata are required. The possibilities of chiasmata between non-homologous chromosomes, of a genetic mechanism in rye which suppresses the pairing of homoeologous chromosomes, and of other factors causing asynapsis and pseudo-synapsis between genetically similar chromosomes are discussed.

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THE TAXONOMY AND NOMENCLATURE OF THE WHEATS, BARLEYS, AND RYES AND THEIR WILD RELATIVES

Canadian Journal of Botany ◽

10.1139/b59-053 ◽

1959 ◽

Vol 37 (4) ◽

pp. 657-684 ◽

Cited By ~ 95

Author(s):

Wray M. Bowden

Keyword(s):

Interspecific Hybrid ◽

Interspecific Hybrids ◽

Diploid Species ◽

Wild Relatives ◽

Hybrid Origin ◽

Wheat Species ◽

Hybrid Complex ◽

Allohexaploid Wheat ◽

Botanical Varieties

The correct name for the tribe that contains the wheats, barleys, and ryes and their wild relatives is TRITICEAE Dumort. The genus Triticum L. emend. is treated to include both the diploid, allotetraploid, and allohexaploid wheats (Triticum L.), and the diploid species and the allotetraploid and allohexaploid species of interspecific hybrid origin that were formerly placed in the genus Aegilops L. In the geuus Triticum L. emend., there are 10 diploid species; one allotetraploid wheat species of hybrid origin (T. turgidum L. emend.) which includes many cultivars, three botanical varieties, and one auto-allohexaploid form; one allohexaploid wheat (T. × aestivum L. emend.) which is a hybrid complex that includes many cultivars; 10 other allotetraploid or allohexaploid species of interspecific hybrid origin; and numerous other artificial and natural interspecific hybrids. Section HORDEUM of the genus Hordeum L. contains the cultivated barleys and their wild relatives which are all classified under one species, H. vulgare L. emend. The taxonomy of the ryes and the genus Secale L. is considered briefly.

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