Genome analysis of Thinopyrum caespitosum

Genome ◽  
1989 ◽  
Vol 32 (1) ◽  
pp. 141-145 ◽  
Author(s):  
Zhi-Wu Liu ◽  
Richard R. -C. Wang
Keyword(s):  
Genome Analysis ◽  
Karyotype Analysis ◽  
Tetraploid Species ◽  
Genomic Constitution ◽  
Meiotic Analyses

Karyotype and meiotic analyses of the triploid hybrids Pseudoroegneria libanotica (Hackel) A. Löve (2n = 2x = 14; SS) × Thinopyrum caespitosum (C. Koch) R. R.-C. Wang (2n = 4x = 28) and T. bessarabicum (Saval &Rayss) A. Löve (2n = 2x = 14; JJ) × T. caespitosum (2n = 4x = 28) were performed to study the genomic constitution of T. caespitosum. Karyotype analysis of T. caespitosum was also carried out. In all karyotypic studies, the observed ratios between the longest and shortest chromosomes in the genome complements of the tetraploid species and triploid hybrids were higher than the hypothetical one based on the assumption that T. caespitosum has both Je and S genomes. This indicates that amphiplasty occurs at both the triploid and tetraploid levels. The hypothesis that T. caespitosum is an autotetraploid, either JJJJ (JJJeJe) or SSSS, is rejected. The meiotic data, 4.83 I + 0.78 rod II + 4.09 ring II + 2.14 III for P. libanotica × T. caespitosum and 5.16 I + 2.71 rod II + 2.16 ring II + 1.99 III for T. bessarabicum × T. caespitosum, support the hypotheses that the former has SSJe and the latter has JJeS as the genome formula. This evidence and that from other relevant hybrids strongly suggest that T. caespitosum is a true allotetraploid with the genome formula JeJeSS.Key words: karyotype, meiosis, phylogeny, amphiplasty, genome, Lophopyrum, Thinopyrum, Agropyron, Pseudoroegneria.

The genome composition of hexaploid Psammopyrum athericum and octoploid Psammopyrum pungens (Poaceae: Triticeae)

Genome ◽  
2003 ◽  
Vol 46 (1) ◽  
pp. 164-169 ◽  
Author(s):  
Pernilla Ellneskog-Staam ◽  
Björn Salomon ◽  
Roland von Bothmer ◽  
Kesara Anamthawat-Jónsson
Keyword(s):  
In Situ Hybridization ◽  
Genome Analysis ◽  
Genomic In Situ Hybridization ◽  
Agropyron Cristatum ◽  
Genome Composition ◽  
Genomic Constitution ◽  
Hybridization Pattern ◽  
Genomic Probe

The genomic constitution of two species in the genus Psammopyrum, i.e., Ps. athericum (2n = 6x = 42) and Ps. pungens (2n = 8x = 56), was studied by genomic in situ hybridization (GISH). In Ps. athericum, one diploid chromosome set hybridized to a genomic probe from Pseudoroegneria ferganensis (St genome), one diploid set to a probe from Agropyron cristatum (P genome), and one diploid set to a probe from Thinopyrum junceiforme (EbEe genomes) or Th. bessarabicum (Eb genome). Substituting the St-genome probe with an L-genome probe from Festucopsis serpentinii resulted in exactly the same hybridization pattern, suggesting a genomic constitution of EStP or ELP for Ps. athericum. The same probes used on Ps. pungens showed two diploid sets of chromosomes hybridizing to the St-genome probe, one diploid set hybridizing to the P-genome probe, and one diploid set hybridizing to the EbEe-genome probe. The L-genome probe hybridized to approximately 14 of the chromosomes that were labeled by the St-genome probe. Hence the genomic constitution for Ps. pungens is proposed to be EStStP or EStLP.Key Words: Psammopyrum athericum, Psammopyrum pungens, in situ hybridization, Elytrigia pycnantha, Elytrigia pungens, genome analysis.

Cytology of Elymus panormitanus and its F1 hybrids with Pseudoroegneria spicata, Elymus caninus, and Elymus dentatus ssp. ugamicus

Genome ◽  
1988 ◽  
Vol 30 (6) ◽  
pp. 879-884 ◽  
Author(s):  
Kevin B. Jensen ◽  
Stephan L. Hatch
Keyword(s):  
Seed Set ◽  
Karyotype Analysis ◽  
The United States ◽  
Intergeneric Hybrids ◽  
F1 Hybrids ◽  
Genomic Constitution ◽  
Pseudoroegneria Spicata ◽  
Elymus Caninus ◽  
Modified Forms ◽  
Sterile Hybrids

Three accessions of Elymus panormitanus (Parl.) Tzvelev were introduced into the United States in 1967 from Iraq and Turkey. A study was undertaken to describe the cytological behavior, mode of reproduction, cytology and fertility of E. panormitanus and its F1 hybrids with "analyzer" species, and genomic formula. Chromosome pairing was studied at meta-phase I in a series of interspecific and intergeneric hybrids to characterize the genomic constitution of E. panormitanus. All plants of E. panormitanus studied were 2n = 28, and averaged 13.96 bivalents per cell, suggesting that E. panormitanus is an allotetraploid with two different genomes. Seed set under controlled pollination indicated that E. panormitanus is highly self-compatible. Hybrids between E. panormitanus and the following analyzer species (with known genomic constitution) were obtained: Pseudoroegneria spicata (Pursh.) A. Love, 2n = 14, SS; Elymus caninus (L.) L., 2n = 28, SSHH; Elymus dentatus (Hook, f.) Tzvelev ssp. ugamicus (Drob.) Tzvelev, 2n = 28, SSYY. All hybrids were highly sterile. Hybrids between E. panormitanus and P. spicata, E. caninus, and E. dentatus ssp. ugamicus averaged 3.93, 3.70, and 7.28 bivalents per cell, respectively. Meiotic data in this series of F1 hybrids and karyotype analysis of E. panormitanus suggested that the genomic formula for E. panormitanus can tentatively be written as SpSpYpYp, indicating that both genomes are modified forms of the S and Y genomes found in the East Asian SY polyploids.Key words: Triticeae, Elymus, phylogeny, hybrids, intergeneric.

scholarly journals Cytogenetic evidence supports Avena insularis being closely related to hexaploid oats.

2021 ◽  
Author(s):  
Esther Ferrer ◽  
Araceli Fominaya ◽  
Yolanda Loarce ◽  
Juan M González
Keyword(s):  
Karyotype Analysis ◽  
Tetraploid Species ◽  
D Genome ◽  
Phylogenetic Studies ◽  
Hexaploid Species ◽  
C Genome ◽  
Cytogenetic Evidence ◽  
Simple Sequence ◽  
Direct Ancestor ◽  
Rule Out

Cytogenetic observations, phylogenetic studies and genome analysis using high-density genetic markers have suggested a tetraploid Avena species carrying the C and D genomes (formerly C and A) to be the donor of all hexaploid oats (AACCDD). However, controversy surrounds which of the three extant CCDD tetraploid species - A. insularis , A. maroccana and A. murphyi - is most closely related to hexaploid oats. The present work describes a comparative karyotype analysis of these three CCDD tetraploid species and two hexaploid species, A. sativa and A. byzantina . This involved the use of FISH with six simple sequence repeats (SSRs) with the motifs CT, AAC, AAG, ACG, ATC and ACT, two repeated ribosomal sequences, and C genome-specific repetitive DNA.  The hybridization pattern of A. insularis with oligonucleotide (AC) 10 was also determined and compared with those previously published for A. sativa and A. byzantina . Significant differences in the 5S sites and SSR hybridization patterns of A. murphyi compared to the other CCDD species rule out its being directly involved in the origin of the hexaploids.  In contrast, the repetitive and SSR hybridization patterns shown by the D genome chromosomes, and by most of the C genome chromosomes of A. maroccana and A. insularis , can be equated with the corresponding chromosomes of the hexaploids.  Several chromosome hybridization signals seen for A. insularis , but not for A. maroccana , were shared with the hexaploid oats species, especially with A. byzantina .  These diagnostic signals add weight to the idea that the extant A. insularis , or a direct ancestor of it, is the most closely related progenitor of hexaploid oats. The similarity of the chromosome hybridization patterns of the hexaploids and CCDD tetraploids was taken as being indicative of homology.  A common chromosome nomenclature for CCDD species based on that of the hexaploid species is proposed.

Morphology and cytology of induced hexaploid of Elymus canadensis and its backcross derivatives—pentaploids, tetrasomics, and trisomics

Genome ◽  
1990 ◽  
Vol 33 (3) ◽  
pp. 389-394 ◽  
Author(s):  
C. H. Park ◽  
P. D. Walton
Keyword(s):  
Tissue Culture ◽  
Chromosome Pairing ◽  
Seed Set ◽  
Chiasma Formation ◽  
Tetraploid Species ◽  
Genomic Constitution ◽  
Stainable Pollen ◽  
Pollen Mother Cells ◽  
Elymus Canadensis ◽  
Mother Cells

A tissue culture induced octoploid of Elymus canadensis was crossed with two accessions ("Canada" and "Montana") of the same tetraploid species to produce hexaploids. Hexaploid (2n = 42) and near-hexaploid progeny (2n = 43 or 40) obtained from the crosses were morphologically vigorous but either partially or completely sterile. Mean frequencies of univalents and trivalents in the hexaploid pollen mother cells at metaphase I were 3 or 4 and 2 to 4 per cell, respectively. In view of the genomic constitution of the parents, the hexaploids were expected to be genomically double triploids. Nevertheless, bivalents, averaging 14–17 per cell, predominated. This might be due to the failure of chiasma formation and chiasma terminalization. One hexaploid plant was backcrossed to the tetraploid. The progeny consisted of one pentaploid and five aneuploids including one tetrasomic and two trisomics. All of the progeny from the backcrosses were less vigorous than aneuploids at the near-hexaploid level. Tetrasomics and trisomics had stainable pollen and a 17–19% seed set. Two trisomic plants were morphologically indistinguishable from each other and predominantly showed chromosome pairing of 14 II + 1 I. This indicates failure of chiasma formation and chiasma terminalization between homologous chromosomes.Key words: Elymus canadensis, hexaploids, tetrasomics, trisomics, meiosis.

Genome analysis of Elytrigia caespitosa, Lophopyrum nodosum, Pseudoroegneria geniculata ssp. scythica, and Thinopyrum intermedium (Triticeae: Gramineae)

Genome ◽  
1993 ◽  
Vol 36 (1) ◽  
pp. 102-111 ◽  
Author(s):  
Zhi-Wu Liu ◽  
Richard R.-C. Wang
Keyword(s):  
Karyotype Analysis ◽  
Diploid Species ◽  
Pollen Grains ◽  
Root Tip ◽  
Meiotic Pairing ◽  
Tetraploid Species ◽  
Thinopyrum Intermedium ◽  
Male Sterile ◽  
Stainable Pollen ◽  
C Banding

To elucidate the genome constitutions of the tetraploid (2n = 4x = 28) species Elytrigia caespitosa, Lophopyrum nodosum, and Pseudoroegneria geniculata ssp. scythica and the hexaploid (2n = 6x = 42) Thinopyrum intermedium, meiotic pairing was studied in these species as well as 10 hybrids. Karyotype analysis with aceto-orcein stained root-tip cells was performed for the four species and the hybrids of T. bessarabicum with E. caespitosa, P. geniculata ssp. scythica, and T. intermedium. Karyotype analysis by Giemsa C-banding was carried out with the three tetraploid species and the two triploid hybrids involving T. bessarabicum. The species behaved as strict allopolyploids. All hybrids were male sterile with few stainable pollen grains. It is concluded from the results that the three tetraploid species have the genome formula JeJeSS and T. intermedium has the formula JeJeJeJeSS. The chromosomes of the Je and S genomes in these species had C-banding patterns differing from each other and from those of the extant diploid species. Based on these findings, the four species investigated should be placed in the same genus or the same section of a genus. However, new combinations are not proposed at this time pending future taxonomic investigation of the genome constitution of Elytrigia repens (L.) Nevski.Key words: genome, hybrid, meiosis, karyotype, chromosome banding, speciation.

Detection Y Chromosome Microdeletions Among Iraq Population in Infertile Patients with Azoospermia and Severe Oligospermia

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Samah A Hammood ◽  
Alaauldeen S M AL-Sallami ◽  
Saleh M Al-Khafaji
Keyword(s):  
Y Chromosome ◽  
Karyotype Analysis ◽  
Semen Analysis ◽  
Obstructive Azoospermia ◽  
Severe Oligozoospermia ◽  
Infertile Men ◽  
Y Chromosome Microdeletions ◽  
Detailed Evaluation ◽  
Health Organization ◽  
Infertile Patients

Objective: To detection of microdeletions of Y chromosome and study the frequency of microdeletions in infertile men with non-obstructive azoospermia or severe oligozoospermia(Middle Euphrates center)in Iraq population. Material and methods: 153 males were included in the study, the casesweredivided into groups according to the infertility etiology and semen analysis according to Word health organization, the frequencies and the characteristicsof Y chromosome microdeletions were investigated in groups. Multiplex PCR was applied to detect the microdeletions. Results:Y chromosome microdeletion was detected in 42 (40.7%) of 153 cases ,Microdeletions in azoospermia showed more frequently detected 28 (52.8%), followed by severe oligospermia 14 (28 %),Microdeletions in the AZFc region were the most common 12 (22.64%), followed by AZFb 11(20.75%) and AZFa 5(9.43%) in azoospermia compared to severe oligospermisAZFc 6 (12%) AZFb 4 (8 %) and AZFa 4 (8%). Conclusion: Y chromosome microdeletions were detected quite frequently in certain infertility subgroups. Therefore, detailed evaluation of an infertile man by physical examination, semen analysis, hormonal evaluationsand when required, karyotype analysis may predict the patients for whom Y chromosome microdeletionanalysis is necessary and also prevent cost increases. Recommendation: This study emphasizes that analysis of microdeletions should be carried out for all patients with idiopathic azoospermia and severe oligospermia who are candidates for intracytoplasmic sperm injection

Advance in genome analysis for human diseases

2009 ◽  
Vol 22 (2) ◽  
pp. 126-130
Author(s):  
Naomichi Matsumoto
Keyword(s):  
Genome Analysis ◽  
Human Diseases
Sign in / Sign up

Export Citation Format

Share Document