Segregation for fertility and meiotic stability in novel Brassica allohexaploids

Two winter hexaploid triticale populations derived from the same cross were selected on the basis of grain appearance and agronomic performance. The five lines from 84LT402 showed more kernel shriveling than the four lines from 84LT401. The derived lines were analyzed for aneuploid frequencies, rye chromosome banding patterns, and meiotic stability to detect associations with kernel development. The aneuploid frequencies were 16% in 84LT401 and 18% in 84LT402. C-banding showed that both selection groups had all the rye chromosomes except 2R. The two groups had similar telomeric patterns but differed in the long-arm interstitial patterns of 4R and 5R. Compared with lines from 84LT402, those from 84LT401 had significantly fewer univalents and rod bivalents, and more paired arms at metaphase I; fewer laggards and bridges at anaphase I; and a higher frequency of normal tetrads. There were no significant differences among lines within each group for any meiotic character. Since there were no differences within or between groups in telomeric banding patterns, the differences in kernel shriveling and meiotic stability might be due to genotypic factors and (or) differences in the interstitial patterns of 4R and 5R. By selecting plump grains, lines with improved kernel characteristics along with improved meiotic stability are obtainable.Key words: triticale, meiotic stability, C-banding, Secale cereale, heterochromatin.

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Domestication in Real Time: The Curious Case of a Trigenomic Sunflower Population

Agronomy ◽

10.3390/agronomy9110704 ◽

2019 ◽

Vol 9 (11) ◽

pp. 704

Author(s):

Jill M. Ekar ◽

Kevin J. Betts ◽

Adam C. Herman ◽

Robert M. Stupar ◽

Donald L. Wyse ◽

...

Keyword(s):

Genetic Correlations ◽

Ground Cover ◽

Hybrid Population ◽

Interspecific Crosses ◽

Oilseed Crop ◽

Selection Efficiency ◽

Perennial Crop ◽

Crop Development ◽

Meiotic Stability ◽

Below Ground

This study chronicles the ongoing process to domesticate an interspecific trigenomic tetraploid hybrid sunflower derived from a series of interspecific crosses between Helianthus annuus and Helianthus tuberosus. The goal of this process is to develop a perennial oilseed crop that can produce both high value vegetable oil and continuous ground-cover. Selection has focused on developing an ideotype with the domesticated morphology of H. annuus and the below-ground perennial features of H. tuberosus. The overarching challenge in the process of breeding and domesticating this interspecific perennial sunflower is overcoming obstacles associated with interploid meiosis in order to resolve a chromosomally stable hybrid population. As selection progresses through generations of intermating, there are improvements toward the desired ideotype, but selection efficiency is slowed by apparent antagonisms between annual- and perennial morphological targets and irregular meiosis which is especially problematic in a trigenomic tetraploid. This shows that keys toward perennial crop development through interspecific hybridization will be to capitalize on the abundant phenotypic variation within our population, achieve meiotic stability in order to maximize selection efficiency, and to break genetic correlations between annual and perennial traits.

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Meiotic stability in two valuable interspecific hybrids of Brachiaria (Poaceae)

Plant Breeding ◽

10.1111/j.1439-0523.2011.01942.x ◽

2012 ◽

Vol 131 (3) ◽

pp. 402-408 ◽

Cited By ~ 2

Author(s):

Mariana F. Felismino ◽

Maria S. Pagliarini ◽

Cacilda B. Do Valle ◽

Rosângela. M. S. Resende

Keyword(s):

Interspecific Hybrids ◽

Meiotic Stability

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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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Meiotic Stability of 56‐Chromosome Tall Fescue Hybrid Derivatives

Crop Science ◽

10.2135/cropsci1991.0011183x003100060030x ◽

1991 ◽

Vol 31 (6) ◽

pp. 1532-1535 ◽

Cited By ~ 3

Author(s):

G. C. Eizenga ◽

P. B. Burrus ◽

J. F. Pedersen ◽

P. L. Cornelius

Keyword(s):

Tall Fescue ◽

Meiotic Stability

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MEIOTIC STABILITY IN CONTROL AND NEWLY COLCHICINE-INDUCED DIHAPLOID BARLEY

Canadian Journal of Genetics and Cytology ◽

10.1139/g79-005 ◽

1979 ◽

Vol 21 (1) ◽

pp. 33-35 ◽

Cited By ~ 5

Author(s):

R. A. Finch ◽

M. D. Bennett

Keyword(s):

Chromosome Number ◽

Breeding Material ◽

Two Generations ◽

Meiotic Stability

Comparison of meiosis in barley plants treated with colchicine when seedling or juvenile haploids and in control dihaploids similarly treated two generations earlier shows that colchicine used to double the chromosome number of barley haploids has no effect on meiosis which could lead to difficulties in screening breeding material.

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Meiotic stability of B chromosomes and production of macrospermatids in Aiolopus strepens (Orthoptera: Acrididae)

Genome ◽

10.1139/g87-002 ◽

1987 ◽

Vol 29 (1) ◽

pp. 5-10 ◽

Cited By ~ 8

Author(s):

J. A. Suja ◽

C. Garcia de la Vega ◽

J. S. Rufas

Keyword(s):

Key Words ◽

Natural Populations ◽

B Chromosomes ◽

Supernumerary Chromosomes ◽

Mitotic Instability ◽

Meiotic Stability ◽

Intercellular Connections

Four males from several Spanish natural populations of Aiolopus strepens were found to carry B chromosomes. These are short and acrocentric and are identical in the different individuals. They show mitotic instability and meiotic stability. When present in odd numbers one unpaired B is generally observed, while in even numbers they usually form bivalents. In no case were lagging B's observed. B chromosomes do not affect nucleolar expression. A significant increase in the number of macrospermatids is found in individuals with B's. This is more pronounced in follicles containing odd numbers of supernumerary chromosomes. A possible explanation based on an assumed influence of B univalents on the maintenance of intercellular connections is discussed. Key words: B chromosomes, spermiogenesis, insect cytogenetics.

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Restoration of meiotic stability following artificial hybridisation and selection in Teleogryllus (Orth., Gryllidae)

Bulletin of Entomological Research ◽

10.1017/s0007485300005459 ◽

1973 ◽

Vol 62 (4) ◽

pp. 557-563 ◽

Cited By ~ 9

Author(s):

T. W. Hogan ◽

P. G. Fontana

Keyword(s):

Sex Ratio ◽

Genetic Control ◽

Sibling Species ◽

Parental Species ◽

Genetic Differences ◽

Hybrid Strain ◽

Cytological Examination ◽

Research Project ◽

Meiotic Stability ◽

Made In

As part of a research project directed at the genetic control of Teleogryllus commodus (Wlk.) in Australia, hybridisation studies have been carried out between T. commodus and the sibling species T. oceanicus (Le Guillou). A cytological examination of a hybrid strain (male progeny of T. commodus × T. oceanicus backcrossed to T. oceanicus) was made in the F4 generation when meiotic stability had been reached. The karyotype was very similar to that of T. oceanicus, suggesting that only those combinations in which the chromosomes were structurally homologous to T. oceanicus survived. But the stridulation pattern of the hybrid males, intermediate between that of the two parental species, and a consistent sex ratio of 2:1 in favour of the males, indicate profound genetic differences from T. oceanicus. These effects are attributed to introgression, with chromosomal material from T. commodus being incorporated in the T. oceanicus genome as an outcome of the initial hybridisation of the two species.

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Nematode Resistance Derived from Wild Beet and its Meiotic Stability in Sugar Beet

Plant Breeding ◽

10.1111/j.1439-0523.1987.tb01150.x ◽

1987 ◽

Vol 99 (1) ◽

pp. 56-64 ◽

Cited By ~ 22

Author(s):

Andrea Brandes ◽

C. Jungand ◽

G. Wricke

Keyword(s):

Sugar Beet ◽

Nematode Resistance ◽

Meiotic Stability ◽

Wild Beet

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Human SP-A: genotype and single-strand conformation polymorphism analysis

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.1994.266.5.l519 ◽

1994 ◽

Vol 266 (5) ◽

pp. L519-L527 ◽

Cited By ~ 7

Author(s):

L. Krizkova ◽

R. Sakthivel ◽

S. A. Olowe ◽

P. K. Rogan ◽

J. Floros

Keyword(s):

Translation Termination ◽

Protein A ◽

Single Strand Conformation Polymorphism ◽

Surfactant Protein ◽

Single Strand ◽

Polymorphism Analysis ◽

Meiotic Stability ◽

Exon 1 ◽

Nigerian Population ◽

Slot Blot Analysis

We have previously characterized two surfactant protein A (SP-A) cDNAs termed 1A and 6A, as well as a 6A allelic variant termed 6A1. These sequences are quite heterogeneous at the 3' untranslated region (3'UT). Differences between 6A and 6A1 alleles include an 11-bp insertion/deletion 407 bases downstream from the start of the translation termination codon and a base pair polymorphism (C or G) in exon 1 (position 1,193; White, Damm, Miller, Spratt, Schilling, Hawgood, Benson, and Cordell. Nature Lond. 317: 361–363, 1985). The 11-bp (GCCCACTGCCT) segment is present in 6A1 and absent in 6A. The 6A/6A genotype, in a small number of specimens, showed a trend toward a higher frequency in the black Nigerian population compared with Caucasians. In this report, we examine the frequency of the 6A genotype in a larger number of samples from Caucasians and black Nigerians as well as the meiotic stability of the 3'UT heterogeneity. Slot-blot analysis and allele-specific oligonucleotide probes have confirmed that the 6A/6A genotype is more frequent in the Nigerian population. Single-strand conformation polymorphisms in the 3'UT appear to be stably inherited by members of a three-generation family, suggesting that these nucleotide variants represent natural polymorphisms in the population.

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