Cytogenetical and Molecular Characterization of Five Commercial Varieties in Trichosanthes anguina L (original) (raw)

Karyotype analyses and studies on the nuclear DNA content in 30 genotypes of potato () L

Cell Biology International, 2004

The cytophotometric estimation of 4C DNA content, and karyotypic and somatic chromosome number analyses were carried out in 30 genotypes comprising seven cultivars and 23 advanced breeding lines of Solanum tuberosum. Detailed karyotype analysis revealed genotype specific chromosomal characteristics and structural alterations in chromosomes of the genome, with a rare phenomenon of aneusomatic (2n = 4x C 2 = 50) condition in cv.K. Chandramukhi. The origin of this variation could be attributed to mitotic non-disjunction in the shoots giving rise to aneusomatic roots. Highly significant variations in the genome length, volume and total form percentage were noted at the cultivar level. The total chromosome length varied from 84.56 mm in cv.K. Pukhraj to 127.62 mm in MS/89-60, with an average value of 100.94 mm G 1.82. Total chromosome volume varied from 57.22 mm 3 in MS/ 92-1090 to 132.64 mm 3 in JW-160. Significant variations in the 4C DNA content (7.28e15.83 pg) were recorded at the cultivar level, with an exceptionally high DNA content (22.24 pg) in cv.K. Chandramukhi. This could be due to the aneusomatic condition of this genotype. Correlation studies revealed interdependence between the chromosomal and nuclear parameters of the genotypes. Structural alterations in the chromosomes, as well as loss or addition of highly repetitive sequences in the genome, caused variations in DNA content at the cultivar level. Variations in genomic structure and nuclear DNA content of the 48-chromosome genotypes suggest a genetic drift during microevolution, leading to the development of new cultivars. Ó

Chromosomal characterization mediated by karyomorphological analysis and differential banding pattern in fenugreek (Trigonella foenum-graecum L.): a neglected legume

Caryologia, 2024

Fenugreek or Trigonella foenum-graecum L. is a commercially important yet neglected crop of the family Fabaceae, with potent medicinal applications, and can treat several diseases as well. Conventional breeding studies for higher yields of commercial crops largely depend on chromosomal information of the particular species. Despite a number of cytological research being conducted on T. foenum-graecum, a complete characterization of its chromosomes has not been achieved due to the limitations of traditional karyotype analysis methods. A range of chromosomal markers are advantageous to characterize at full extent and identify individual chromosomes rather than relying on only physical metrics. Thus, in this study, in addition to giemsa staining, other approaches like fluorochrome and silver staining were used for the precise karyomorphological analysis of this species. Enzyme maceration and air drying (EMA) based fluorochrome banding with GC-specific stain Chromomycin A3 (CMA), and AT-specific stain 4' ,6-diamidino-2-phenylindole (DAPI) applied for the first time for chromosome characterization. The results showed 2n = 16 chromosomes in metaphase cells, with karyotype formula of 2m+6sm. The unique banding pattern observed in the CMA/DAPI and AgNOR staining highlights the AT and GC-rich regions as well as the nucleolar organizer regions (NORs). All this crucial information can further assist in conducting breeding studies of more precision with simultaneously encouraging similar studies that need to be done in other unexploited species of importance.

Cytogenetics and Chromosome Analytical Techniques

Floriculture, Ornamental and Plant Biotechnology: Advances and Topical Issues Vol. IV, 2006

Chromosome analysis techniques for maize and its relatives are described. These approaches should be universally applicable to plant species. Procedures are described that result in improved signal strength for Fluorescence in situ hybridization (FISH) procedures. These improvements allow localization of individual genes, including transgenes, to specific chromosomal locations. To identify each chromosome in the karyotype, a set of tandemly arranged repetitive sequences was assembled. The copy number of the elements in the individual arrays varied from line to line. Also, the method of Retroelement Genome Painting is described that uses specific retrotransposons, which have amplified differentially in the genomes of related species to permit the distinction of diverged chromosomes in interspecific hybrids or allopolyploids. Cytological visualization of chromosomes using this technique can reveal evolutionary relationships between species and guide attempts to introgress portions of one genome into another.

Genetic Identification of Diploid and Tetraploid Wheat Species with RAPD Markers

Turk J Biol, 2007

The genetic diversity of 10 diploid and tetraploid wheat species was estimated using random amplified polymorphic DNA (RAPD) markers. Two species from diploid [Triticum boeticum (wild), Triticum monococcum] and five from tetraploid wheats [Triticum dicoccoides var. arabicum (wild), Triticum dicoccum var. farrum, Triticum dicoccum var. atratum, Triticum durum var. hordeiforme (Bereketli 95), Triticum durum var. leucurum (Sharq), Triticum turgidum var. alboyadurum, Triticum turgidum var. salomonis and Triticum persicum] were included for the analyses. Jacard’s cluster analysis algorithm was used to determine genetic similarities. There were two main classes in dendrogram: the varieties [T. boeticum, T. dicoccoides var. arabicum, T. dicoccum var. farrum, T. dicoccum var. atratum, T .durum var. hordeiforme (Bereketli 95), T. durum var. leucurum (Sharq)] assembled in one group and the species [T. monococcum, T. turgidum var. alboyadurum, T. turgidum var. salomonis and T. persicum] in another. The same genotypes were also assessed in field conditions for structural analyses, which were carried out based on eight yield components. The dendrogram created was comparatively analyzed with the RAPD dendrogram. There were differences between genetic and phenotypic similarity of the studied accessions. Results indicated that some of genetically similar genotypes were different phenotypically.

Chromosomal studies in the Egyptian flora. II. Karyotype studies in the genus Plantaga L

CYTOLOGIA, 1987

The first reliable chromosome counts in species of the genus Plantago L. was made by . Later more detailed cytological investigations were carried out on more than half of the species in this genus. Some of these investigations were made in connection with taxonomic studies in order to elucidate the relationships in particular groups of related species . Other studies were concerned with investigating the cytology of Plantago species in certain floras or phytogeographic regions .

Molecular Cytogenetics ofMusaSpecies, Cultivars and Hybrids: Location of 18S-5.8 S-25S and 5S rDNA and Telomere-like Sequences

Annals of Botany, 1998

The physical sites of 18S-5.8 S-25S and 5S rRNA genes and telomeric sequences in theMusaL. genome were localized by fluorescentin situhybridization on mitotic chromosomes of selected lines. A single major intercalary site of the 18S-5.8 S-25S rDNA was observed on the short arm of the nucleolar organizing chromosome in each genome. AA and BB genome diploids had a single pair of sites, triploids had three sites while a tetraploid hybrid had four sites. The probe is useful for quick determination of ploidy, even ...

Genotypic variations of ten Indian cultivars ofColocasia esculentavar.antiquoromSchott. evident by chromosomal and RAPD markers

Caryologia, 2015

Detailed karyotype, genome size and RAPD marker analysis were employed to assess genetic diversity in Taro (Colocasia esculenta var antiquorom Schott.). Karyotype analysis revealed genotype specific chromosomal characteristics and structural alterations in chromosome with variations of ploidy from 2n = 2x = 28 (cv. Mothan, cv. Muktakeshi, cv. Sree Kiran, cv. Sree Pallavi, cv. Sunajhili) to 3n = 3x = 42 (cv. Banky, cv. DP-25, cv. Duradin, cv. H-3, cv. Telia) in the genome. Highly significant variations in the genomic length, volume and total form (TF) % were noted at variety level. Total genomic chromosome length varied from 46.96μm in cv. Sree Kiran to 100.49μm in cv. Duradin. Total genomic chromosome volume varied from 18.22μm 3 in cv. Sunajhili to 38.22μm 3 in cv. Duradin. Total form percentage was varied from 24.94% in cv. Sree Kiran to 39.04% in cv. H-3 confirming near metacentric to metacentric chromosomes in the karyotype. Significant variations in the 4C DNA content noted among the cultivars that ranged from 7.24 pg in cv. Sree Kiran to 18.24 pg in cv. Duradin; accordingly, genome size varied from~7095 to 17875 Mbp. High genome size in all the triplod varieties with 3x = 42 chromosomes could be due to the presence of extra set of chromosomes in the genome or high amount of repetitive DNA. The variation in the genome size at the variety level might be attributed to loss or addition of highly repetitive sequences in the genome. Amplification of genomic DNA in 10 genotypes using Operon primers yielded 230 amplified DNA fragments, ranging in size from 200 to 2500bp out of which 79 bands were polymorphic. A total of 8 unique RAPD bands were observed among 10 taro genotypes that revealed primer wise polymorphism ranged from 16.66 to 47.36% with an average polymorphic percentage of 34.34%. Whereas, among the cultivars the polymorphic percentage varied from 3.70% between cv. DR-25 & cv. Duradin and cv. Telia & cv. H-3 to 41.94% between cv. Mothan & cv. Muktakeshi. Genetic similarity based on Jaccard's coefficient varied from 0.54 to 0.96, indicating wide genetic variability among the varieties based on RAPD markers. Similarity measures and cluster analysis generally reflected the expected trends in relationships of diploid and triplod taro varieties. Dendrogram obtained from the genetic distances among the varieties could be useful for breeders to choose the diverse parents for breeding programme aimed at varietal improvement.

A preliminary report on the genetic variation in pointed gourd (Trichosanthes dioica Roxb.) as assessed by random amplified polymorphic DNA

Acta biologica Hungarica, 2014

Pointed gourd (Trichosanthes dioica Roxb.) is an economically important cucurbit and is extensively propagated through vegetative means, viz vine and root cuttings. As the accessions are poorly characterized it is important at the beginning of a breeding programme to discriminate among available genotypes to establish the level of genetic diversity. The genetic diversity of 10 pointed gourd races, referred to as accessions was evaluated. DNA profiling was generated using 10 sequence independent RAPD markers. A total of 58 scorable loci were observed out of which 18 (31.03%) loci were considered polymorphic. Genetic diversity parameters [average and effective number of alleles, Shannon's index, percent polymorphism, Nei's gene diversity, polymorphic information content (PIC)] for RAPD along with UPGMA clustering based on Jaccard's coefficient were estimated. The UPGMA dendogram constructed based on RAPD analysis in 10 pointed gourd accessions were found to be grouped in a...