CONTRIBUTION A L'ETUDE CYTOTAXONOMIQUE D'ESPECES MEDITERRANEENNES D'ANEMONE ET DE LEURS HYBRIDES

1976 ◽  
Vol 18 (1) ◽  
pp. 151-168 ◽  
Author(s):  
Nicole Maïa ◽  
P. Venard
Keyword(s):  
Interspecific Hybrids ◽  
Meiotic Abnormalities ◽  
Meiotic Behavior ◽  
Statistical Comparison ◽  
Chromosomal Pair ◽  
Chromosome Alteration ◽  
Cultivated Species ◽  
Alien Cytoplasm ◽  
Tetraploid Level ◽  
Good Agreement

Statistical comparison of the caryotypes of the four Mediterranean Anemone species: A. palmata L., A. coronaria L., A. pavonina Lamk. and A. hortensis L., is based on the dispersion areas of the T/Θ and L/C parameters estimated for each chromosomal pair. Chromosome alteration has been observed in both interspecific hybrids obtained. These alterations are more marked when the genome is transferred into an alien cytoplasm. The F1 hybrid A. pavonina × A. hortensis is fertile with some meiotic abnormalities. Sterility of the A. pavonina × A. coronaria F1 hybrid is caused by the failure of pairing. Chromosomal doubling by colchicine restored fertility. Phylogenic relations as established by morphological, biochemical and caryotypic characters, as well as by meiotic behavior of interspecific hybrids, are in good agreement. The lack of introgression of new characters into the cultivated species A. coronaria is due to interspecific sterility barriers. Nevertheless, the introduction of the coronaria genome into the cytoplasm of pavonina would be a source of male-sterility at the tetraploid level.

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

2019 ◽  
Vol 19 (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.

scholarly journals Meiotic analysis in induced tetraploids of Brachiaria decumbens Stapf

2011 ◽  
Vol 11 (1) ◽  
pp. 43-49 ◽  
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.

scholarly journals Cytogenetic characterization of Aloysia virgata Ruiz and Pavan (Verbenaceae)

2009 ◽  
Vol 52 (4) ◽  
pp. 893-899
Author(s):  
Aline Dias Brandão ◽  
Lyderson Facio Viccini ◽  
Shirlei Maria Recco-Pimentel
Keyword(s):  
Interphase Nucleus ◽  
5S Rdna ◽  
Nucleolar Organizer ◽  
Nucleolar Organizer Regions ◽  
Meiotic Behavior ◽  
Meiotic Analysis ◽  
Chromosomal Pair ◽  
Cytogenetic Characterization

Since previous cytogenetic reports of Aloysia have only described the meiotic behavior and chromosomal number of some species, the aim of this work was to provide detailed cytogenetic description of Aloysia virgata that would contribute to the understanding of the taxonomical organization of the Verbenaceae. Aloysia virgata had a karyotype with 2n = 36 metacentric chromosomes, all with similar size. The large amount of heterochromatin seen after Giemsa staining was confirmed by C-banding. Four nucleolar organizer regions (NORs) were detected with an rDNA 45S probe in two homologous pairs and two sites of 5S rDNA located on one chromosomal pair were detected by fluorescence in situ hybridization. The interphase nucleus was classified as semi-reticulate. Meiotic analysis showed a normal chromosomal behavior, with 18 bivalents in some parts of prophase I and in metaphase I. The number of chromosomes, NORs and 5S rDNA segments did not exclude a possible polyploid origin.

Meiotic behavior in interspecific hybrids between Brachiaria ruziziensis and Brachiaria brizantha (Poaceae)

Euphytica ◽  
2005 ◽  
Vol 145 (1-2) ◽  
pp. 155-159 ◽  
Author(s):  
Claudicéia Risso-Pascotto ◽  
Maria Suely Pagliarini ◽  
Cacilda Borges do Valle
Keyword(s):  
Interspecific Hybrids ◽  
Meiotic Behavior ◽  
Brachiaria Brizantha ◽  
Brachiaria Ruziziensis

Interspecific hybrids between a transgenic rapeseed (Brassica napus) and related species: cytogenetical characterization and detection of the transgene

Genome ◽  
1993 ◽  
Vol 36 (6) ◽  
pp. 1099-1106 ◽  
Author(s):  
M. C. Kerlan ◽  
A. M. Chevre ◽  
F. Eber
Keyword(s):  
Chromosome Pairing ◽  
Related Species ◽  
Interspecific Hybrids ◽  
Plant Production ◽  
Triploid Hybrid ◽  
Bar Gene ◽  
Meiotic Behavior ◽  
Gene Dispersal ◽  
Gene Characterization ◽  
Transgenic Rapeseed

In interspecific hybrids produced between a transgenic rapeseed, an allotetraploid species, resistant to herbicide, phosphinotricin, and five diploid related species, the risk for gene introgression in weed genomes was explored through cytogenetic and bar gene characterizations. Among the 75 hybrids studied, most had the expected triploid structure, with the exception of B. napus – B. oleracea amphidiploid plants and one B. napus – S. arvensis amphidiploid plant. In triploid hybrid plants, the reciprocal hybrids did not exhibit any difference in their meiotic behavior. The comparison of the percentage of chromosome pairing in the hybrids with that of haploid rapeseed permit to conclude that allosyndesis between AC genomes and related species genomes took place. This possibility of recombination was confirmed by the presence of multivalent associations in all the interspecific hybrids. Nevertheless, in B. napus – B. adpressa hybrids a control of chromosome pairing seemed to exist. The possibility of amphidiploid plant production directly obtained in the F1 generation increased the risk of gene dispersal. The B. napus – B. oleracea amphidiploid plant presented a meiotic behavior more regular than that of the B. napus – S. arvensis amphidiploid plant. Concerning the herbicide bar gene characterization, the presence of the gene detected by DNA amplification was correlated with herbicide resistance, except for two plants. Different hypotheses were proposed to explain these results. A classification of the diploid species was established regarding their gene dispersal risk based on the rate of allosyndesis between chromosomes of AC genomes of rapeseed and the genomes of the related species.Key words: Brassicaceae, transgenic rapeseed, risk assessment, interspecific hybrids, chromosome pairing, bar gene characterization.

HYBRIDIZATION BETWEEN ANNUAL AND PERENNIAL DIPLOID SPECIES OF HELIANTHUS

1978 ◽  
Vol 20 (4) ◽  
pp. 523-530 ◽  
Author(s):  
Ernest D. P. Whelan
Keyword(s):  
Interspecific Hybrids ◽  
Diploid Species ◽  
Paracentric Inversion ◽  
Sterile Hybrid ◽  
Meiotic Behavior ◽  
Perennial Species ◽  
Annual Species ◽  
Normal Pollen

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.

scholarly journals Microsporogenesis in Brachiaria bovonei (Chiov.) Robyns and B. subulifolia (Mez) Clayton (Poaceae)

2009 ◽  
Vol 66 (5) ◽  
pp. 691-696 ◽  
Author(s):  
Claudicéia Risso-Pascotto ◽  
Maria Suely Pagliarini ◽  
Cacilda Borges do Valle
Keyword(s):  
Chromosome Number ◽  
High Frequency ◽  
Germplasm Collection ◽  
Meiotic Abnormalities ◽  
Meiotic Behavior ◽  
African Species ◽  
Germplasm Collections ◽  
Chromosome Stickiness ◽  
The Tropics ◽  
New Cultivars

Some African species of Brachiaria have been introduced into the Americas and became the most important forage for pastures in the tropics. New cultivars can be obtained either from direct selections from the natural existing variability in the germplasm collections or from interspecific hybridizations. Polyploidy is predominant in the genus Brachiaria and correlated with apomixis which complicates hybridization. The objective of cytological studies underway on the Brachiaria germplasm collection at Embrapa Beef Cattle is to determine the chromosome number and meiotic behavior of accessions. For the breeding of Brachiaria species, compatible sexual and apomictic accessions need to be identified. Microsporogenesis was evaluated in two accessions of Brachiaria bovonei (BO01 and BO05) and one accession of B. subulifolia (SU01). BO01 is pentaploid (2n = 5x = 45), BO05 is tetraploid (2n = 4x = 36), and SU01 is hexaploid (2n = 6x = 54), derived from x = 9. Meiotic abnormalities typical of polyploids, characterized by precocious chromosome migration to the poles in metaphases, laggard chromosomes in anaphases, and micronuclei in telophases and tetrads, were recorded in high frequency in all the accessions generating unbalanced gametes. Both accessions of B. bovonei presented chromosome stickiness. The results are discussed in the view of the Brachiaria breeding program objectives.

Diploid-like meiotic behavior in synthesized amphiploids of the genus Glycine Willd. subgenus Glycine

1985 ◽  
Vol 27 (6) ◽  
pp. 655-660 ◽  
Author(s):  
R. J. Singh ◽  
T. Hymowitz
Keyword(s):  
Chromosomal Instability ◽  
Interspecific Hybrids ◽  
Meiotic Behavior ◽  
Preferential Pairing ◽  
Homologous Chromosomes ◽  
Tetraploid Hybrid

Six amphiploids consisting of one allotetraploid (2n = 4x = 80), four allohexaploids (2n = 6x = 120), and one allooctoploid (2n = 8x = 160) were synthesized by doubling the chromosomes of F1 interspecific hybrids of the following parents: one diploid (Glycine latifolia 2n = 2x = 40 × G. clandestina, short pod (Sp), 2n = 2x = 40); four triploids (G. clandestina, Sp, 2n = 2x = 40 × G. tabacina 2n = 4x = 80), (G. tabacina 2n = 4x = 80 × G. canescens 2n = 2x = 40), (G. tomentella2n = 4x = 80 × G. canescens 2n = 2x = 40 and its reciprocal); and one tetraploid (G. tomentella2n = 4x = 80 × G. tabacina 2n = 4x = 80). Chromosomal chimerism was observed in the C1 generation. Pod set was recorded in all the colchicine-treated hybrids except in the tetraploid hybrid of G. tomentella × G. tabacina. In C2 generation plants, chromosomal instability was noticed only in the allohexaploid of G. tabacina × G. canescens. All of the amphiploids showed diploid-like meiosis in the majority of the sporocytes and did not exhibit expected multivalent associations, a classical example of allopolyploidy. This was attributed to strong preferential pairing between homologous chromosomes which may be under genetic control.Key words: Glycine, synapsis, interspecific hybrids.

GENETIC RELATIONSHIPS BETWEEN DIPLOIDS AND TETRAPLOIDS IN SERIES EUBARBATAE OF AVENA

1968 ◽  
Vol 10 (1) ◽  
pp. 68-81 ◽  
Author(s):  
Gideon Ladizinsky ◽  
Daniel Zohary
Keyword(s):  
Gene Flow ◽  
Genetic Relationships ◽  
Extreme Case ◽  
Meiotic Behavior ◽  
Ploidy Levels ◽  
Single Genome ◽  
In Series ◽  
Full Shift ◽  
Tetraploid Level ◽  
Diploid Level

Diploid (2n = 14) and tetraploid (2n = 28) entities in series Eubarbatae of the genus Avena have been found to be genetically closely linked and are regarded as a single polyploid complex. At both ploidy levels the various morphological types are interfertile. Diploids and tetraploids are largely sympatric in their distribution and converge considerably in their ranges of morphological variation. Contacts between diploids and tetraploids are common and blurred morphological boundaries characterize mixed populations.The possibility of gene flow between diploids and tetraploids has been indicated by the behavior of triploid F1 hybrids. Such hybrids have been found to be partially fertile. In their progeny a conspicuous restoration of fertility is apparent: numerous plants of the F2 generation have been stabilized around the tetraploid level, few around the diploid level. In contact areas, triploids can be regarded as efficient bridges of gene flow between the two ploidy levels.The range of variation found at the tetraploid level is fully explicable by the variation present in the diploid races. Tetraploids are therefore regarded to have had an inter-varietal origin, i.e. have evolved from a single genome. They apparently represent an extreme case of bivalentization, where a full shift from an autotetraploid to an allotetraploid meiotic behavior had occurred. Meiotic behavior of the F2 plants also indicate such origin.

scholarly journals Pre-fertilization Barrier, Crossability and Meiotic Behavior of Interspecific Hybrids Among Brassica Species

2021 ◽  
Author(s):  
Usha Pant ◽  
Shikha Joshi ◽  
Preeti Lohani ◽  
Neha Dahiya
Keyword(s):  
Pollen Tube ◽  
Interspecific Hybrids ◽  
Brassica Species ◽  
Correlation Study ◽  
Plant Evolution ◽  
Pollen Parent ◽  
Phenotypic Characterization ◽  
Meiotic Abnormalities ◽  
Naturally Occurring ◽  
Specific Hybridization

Abstract Inter-specific hybridization is an important driving force in plant evolution, speciation and creation of novel genetic variations those are not available with the naturally occurring species. Present investigation includes study of pre-fertilization barriers, phenotypic characterization and the meiotic abnormalities during microsporogenesis in the interspecific hybrids. Mean pollen tube germination percent in interspecific hybrids was recorded to be highest in case of B. carinata x B. nigra (33.67±11.35) and lowest between B. carinata x B. napus (18.68±6.62) whereas in the reciprocal crosses it was highest for B. napus x B. carinata (33.06±13.41). Siliqua set ranged from 33% in B. carinata x B. napus to 72% in selfedB. carinata. Seed set % ranged from 0% in B. rapa x B. carinata and B.nigra x B.carinatato 25.64 % for B. carinata x B.nigra. Mean pollen tube growth was recorded highest in B. carinata x B. nigra (21.23±5.33) while was lowest in B. carinata x B. napus (10.18±3.17) and among reciprocals it was highest for B. nigra x B. carinata (21.39±7.53). Pollen tube abnormalities viz., coiling and bending of pollen tube, hairpin shaped pollen tube, swelling of tube tip, tube bifurcation, more than one tube emerging from pollen, tubes growing in wrong direction were observed. B. carinata as pollen parent showed highest mean pollen tube abnormality percent with B. napus (36.32±8.62) whereas lowest with B. nigra (18.09±6.73). It was observed highest with B. rapa (49.170 ±13.55) when B. carinata was used as pollen parent. Some of the pre fertilization barriers related to stylar and ovule region can also be observed through fluroscent microscopy. As per the observations B. carinata performed better as a seed parent with B. nigra, B. juncea and B. rapa whereas, with B. napus it performed good as a pollen parent. Correlation study gave the association the above traits with each other. The meiotic abnormalities showed improper alignment at M-I, M-II, A-I, A-II and Telophase.

Sign in / Sign up

Export Citation Format

Share Document