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E D Badaeva

Publications and source records attributed to E D Badaeva.

13 recordsLinked to original sources
PubMed2006

[Cytogenetic analysis of alloplasmic recombinant lines (H. vulgare)-T. aestivum with unstable fertility and viability].

Comparative cytogenetic analysis was performed with four alloplasmic recombinant (Hordeum vulgare)-Triticum aestivum lines differing in morphological traits, number of seeds per spike, and seed plumpness. None of the lines displayed introgression of the barley genetic material: the karyotypes included only common wheat chromosomes. Two lines, 79(B) and 79(D), were cytogenetically stable. Plants of lines 79(A) and 79(C) displayed a high frequency of unbalanced chromosome aberrations, including dicentric and polycentric chromosomes, terminal deletions varying in size, acentric fragments, and multiple unidentifiable translocations. Previous studies of the mitochondrial genome showed that the two cytologically unstable lines, which were also unstable in fertility and viability, are characterized by heteroplasmy at the mitochondrial 18S-5S locus (simultaneous presence of barley and wheat fragments). Stable lines 79(B) and 79(D) with normal fertility contained only wheat mitochondrial markers. It was assumed that the substantial instability of the nuclear genome in lines 79(C) and 79(A) was a result of nuclear-cytoplasmic incompatibility and was associated with heteroplasmy, while elimination or considerable reduction of barley material in the mitochondrial genome stabilized the nuclear genome of lines 79(B) and 79(D). In turn, the instability of the nuclear genome was responsible for a decrease in viability and fertility of plants.

Chimera↗
PubMed2005

[Identification of an alien chromosome in the common wheat line multi 6R].

The chromosome of Agropyron intermedium (Host) Beauv. substituting chromosome 6D has been identified in the karyotype of the Triticum aestivum L. line Multi 6R with the use of C-banding. The alien chromosome, temporarily designated 6Ag1, contains gene(s) of the resistance to the Saratov population of Puccinia recondita Rob. ex. Desm. f. tritici. It has been demonstrated that the resistance gene(s) is(are) highly efficient and that chromosome 6Ag1 is preferably transferred through gametes.

Agropyron↗
PubMed2005

[Cytogenetic analysis of diploid Avena L. species containing the as genome].

Cytogenetic examination showed that three diploid oat species containing the As genome are highly similar in karyotype structure and chromosome C-banding patterns. Avena strigosa is more similar to A. wiestii, while A. hirtula is to an extent separated from the two species, differing in the C-banding pattern of chromosome 6. The karyotypes of all three species harbor a small acrocentric chromosome, which is absent from diploid oat species containing other variants of the A genome. The results made it possible to assume genome specificity of the rearrangement resulting in this chromosome.

Avena↗
PubMed2004

[Analysis of intraspecific divergence of hexaploid wheat Triticum spelta L. by chromosome C-banding].

Intraspecific divergence of hexaploid wheat Triticum spelta was studied by chromosome C-banding in 41 accessions of different geographic origins. The spelt accessions did not differ in karyotype structure or heterochromatin distribution from common wheat, but showed greater intraspecific polymorphism for chromosome rearrangements (translocations, inversions) and banding patterns. On evidence of C-banding patterns, spelt was assumed to occupy an intermediate position between tetraploid and hexaploid wheat species. Accessions of the Asian spelt subspecies had more diverse banding patterns than European accessions. A relatively high frequency of chromosome rearrangements was observed in Iranian accessions. Visual analysis revealed high uniformity of chromosome banding patterns in T. spelta populations of Afghanistan, Spain, and Germany (Bavarian group), suggesting a significant role of the founder effect in their evolution.

Afghanistan↗
PubMed2004

[Molecular study and C-banding of chromosomes in common wheat alloplasmic lines obtained from the backcross progeny of barley-wheat hybrids Hordeum vulgare L. (2n = 14) x Triticum aestivum L. (2n = 42) and differing in fertility].

We studied common wheat alloplasmic lines differing in fertility traits, which had been obtained from the backcross progeny of barley-wheat hybrids Hordeum vulgare L. (2n = 14) x Triticum aestivum L. (2n = 42), using molecular analysis and chromosome C-banding. It was found that the nuclei of all alloplasmic lines studied, regardless of their fertility traits, contained only the common wheat chromosomes (2n = 42). The formation of line L-79(10)(3)F6, stable for self-fertility, from line L-79(10)(3)F6 was accompanied by changes of the proportions of simple sequence repeats of the parental common wheat varieties in the nuclear genome. The presence of barley genome fragments in line accessions with incomplete self-fertility was shown by RAPD. Heteroplasmy for mitochondrial genome loci was detected in these lines with the use of primers specific to the tMet-18S-5S repeat of mitochondrial ribosomal genes.

Chimera↗
PubMed2003

[Effect of substituting chromosome 5A with an supernumary chromosome 5B in offspring of a somaclonal common wheat line monosomic for 5A].

Cytogenetic analysis was employed in studying the cause of generation of fertile awned forms in the progeny of plants, which were selected from a speltoid somaclonal wheat line monosomic for chromosome 5A (2n = 41 = 20II + I), had speltoid spikes, and were reproduced by self pollination. On cytogenetic and genetic evidence, chromosome 5A was eliminated and the copy number of chromosome 5B increased in the plants examined. The appearance of an extra chromosome 5B is probably caused by nondisjunction of bivalent 5B in the presence of a telocentric originating from the long arm of chromosome 5A. A difference in meiotic segregation was observed for univalent chromosomes 5A and 5B.

Chromosomes, Plant↗
PubMed2002

[Evaluation of phylogenetic relationships between five polyploid Aegilops L. species of the U-genome cluster by means of chromosomal analysis].

Four tetraploid (Aegilops ovata, Ae. biuncialis, Ae. columnaris, and Ae. triaristata) and one hexaploid (Ae. recta) species of the U-genome cluster were studied using C-banding technique. All species displayed broad C-banding polymorphism and high frequency of chromosomal rearrangements. Chromosomal rearrangements were represented by paracentric inversions and intragenomic and intergenomic translocations. We found that the processes of intraspecific divergence of Ae. ovata, Ae. biuncialis, and Ae. columnaris were probably associated with introgression of genetic material from other species. The results obtained confirmed that tetraploid species Ae. ovata and Ae. biuncialis occurred as a result of hybridization of a diploid Ae. umbellulata with Ae. comosa and Ae. heldreichii, respectively. The dissimilarity of the C-banding patterns of several chromosomes of these tetraploid species and their ancestral diploid forms indicated that chromosomal aberrations might have taken place during their speciation. Significant differences of karyotype structure, total amount and distribution of C-heterochromatin found between Ae. columnaris and Ae. triaristata, on the one hand, and Ae. ovata and Ae. biuncialis, on the other, evidenced in favor of different origin of these groups of species. In turn, similarity of the C-banding patterns of Ae. columnaris and Ae. triaristata chromosomes suggested that they were derived from a common ancestor. A diploid species Ae. umbellulata was the U-genome donor of Ae. columnaris and Ae. triaristata; however, the donor of the second genome of these species was not determined. We assumed that these tetraploid species occurred as a result of introgressive hybridization. Similarity of the C-banding patterns of chromosomes of Ae. recta and its parental species Ae. triaristata and Ae. uniaristata indicated that the formation of the hexaploid form was not associated with large modifications of the parental genomes.

Chromosome Aberrations↗
PubMed2001

[Localization of DNA probes for human ribosomal genes on barley chromosomes].

To estimate the possibility of plant genome mapping using human genome probes, the probes fluorescent in situ hybridization (FISH) of human 18S-28S rDNA (clon 22F9 from the LA-13NCO1 library) was carried out on chromosomes of the spring barley Hordeum vulgare L. As a control, wheat rDNA probe (clon pTa71) was taken. Hybridization of the wheat DNA probe revealed two major labelling sites on mitotic barley chromosomes 5I (7H) and 6I (6H), as well as several minor sites. With the human DNA probe, signals were detected in the major sites of the ribosomal genes on chromosomes 5I (7H) and 6I (6H) only when the chromosome preparations were obtained using an optimized technique with obligatory pepsin treatment followed by hybridization. Thus, this study demonstrates that physical mapping of plant chromosomes with human DNA probes that are 60 to 75% homologous to the plant genes is possible. It suggests principal opportunity for the FISH mapping of plant genomes using probes from human genome libraries, obtained in the course of the total sequencing of the human genomes and corresponding to the coding regions of genes with known functions.

Chromosomes↗
PubMed2000

[Cytogenetic analysis of hybrids resistant to yellow rust and powdery mildew obtained by crossing common wheat (Triticum aestivum L., AABBDD) with wheat of the Timopheevi group (AtAtGG)].

The karyotypes of 47 hybrid lines obtained from crosses of common wheat Triticum aestivum L. (cv. Rodina and line 353) with Triticum timopheevii Zhuk, (AtAtGG) and related species T. militinae Zhuk. et Migusch. (AtAtGG) and T. kiharae Dorof. et Migusch. (AtAtGGDsqDsq) were analyzed by C-banding. Most lines were resistant to yellow rust and powdery mildew. The introgression of alien genetic material to the common wheat genome was realized via substitutions of complete At-, G-, and D-genome chromosomes, chromosome arms, or their fragments. The pattern of chromosome substitutions in resistant lines differed from that in introgressive hybrids selected for other traits. Substitutions of chromosomes 6G, 2At, 2G, and 5G were revealed in 31, 23, 18, and 13 lines, respectively. Substitutions of chromosomes 4G-, 4At, and 6At were not observed. In 15 lines, a 5BS. 5BL-5GL translocation was identified. High frequency of substitutions of chromosomes 2At, 2G, 5G, and 6G indicate that they may carry the resistance genes and that they are closely related to the respective homoeologous chromosomes of common wheat that determines their high compensation ability.

Fungi↗
PubMed1998

Molecular cytogenetic analysis of tetraploid and hexaploid Aegilops crassa.

The distribution of highly repetitive DNA sequences on chromosomes of tetraploid and hexaploid cytotypes of Aegilops crassa (Dcr1Xcr and Dcr1XcrDcr2 genomes) was studied using C-banding and in situ hybridization analyses with the pSc119, pAs1 and pTa794 DNA clones. In total, 14 tetraploid and five hexaploid accessions were examined. All chromosomes can be identified by their C-banding and ISH pattern with the pAs1 DNA clone. Only a few pSc119 hybridization sites were observed in the telomeric regions of several chromosomes. We found a high level of C-banding polymorphism and only minor variations in labeling patterns. The position of C-bands generally coincided with the location of the pAs1 sequence. Three 5S rDNA loci were detected in tetraploid Ae. crassa, whereas five pTa794 ISH sites were observed in 6x Ae. crassa. All the hexaploid accessions differed from the tetraploids by a reciprocal non-centromeric translocation involving chromosomes A and N. Three additional translocations were detected in the accessions analyzed. The Dcr1 genome of 4x Ae. crassa is highly modified compared with the D genome of the progenitor species Ae. tauschii. Because of the large amount of chromosomal rearrangements, the origin of the Xcr genome remains unknown. The second Dcr2 genome of 6x Ae. crassa is different from the Dcr1 genome but is similar to the D-genome chromosomes of Ae. tauschii, indicating that no additional large rearrangements occurred at the hexaploid level.

Chromosome Banding↗
PubMedDate not supplied

[Introduction to plant genomics].

The success in complete sequencing of "small" genomes and development of new technologies which sharply accelerate processes of cloning and sequencing made real an intensive development of plant genomics and complete sequencing of DNA of some species. It is assumed that the success in plant genomics will result in revolutionary changes in biotechnology and plant breeding. However, the enormous size of genomes (tens of billions bp), their extraordinary enrichment in repetitive sequences, and allopolyploidy (the presence in a nucleus of several related but not identical genomes) force us to think that only few "basic" will undergo complete sequencing, whereas the genome investigations in other species will follow principles of comparative genomics. By the present time, complete sequencing of the Arabidopsis genome (125 Mbp) is completed and that of the rice genome (about 430 Mbp) is close to its end. Studying other plant genomes, including those economically valuable, already began on the basis of these investigations. Peculiarities of plant genomes make extraordinarily important the knowledge on plant chromosomes which, in its turn, requires expansion of investigations in this direction and development of new chromosome technologies, including the DNA-sparing methods of high-resolution banding.

Chromosomes↗
PubMedDate not supplied

[History of modern chromosomal analysis. Differential staining of plant chromosomes].

Differential staining methods found extensive use in karyotype studies of many plant and animal species and provide for reliable identification of all chromosomes of the organism. Below we describe the most widespread methods and history of their advent. In addition, we discuss specific structure of the chromosomes and possible mechanisms responsible for differential segmentation.

Chromosomes, Plant↗