Synthetic B. napus was produced through interspecific hybridization between nine varieties of B. rapa and only one exotic variety of B. oleracea var. alboglabra along with exogenous application of gibberellic acid (GA₃) before pollination. A total of eighteen crosses including their reciprocals were made between the two species. Crossability in both way directions between the two species of Brassica was not equally success. The degree of success was significantly influenced by maternal genotypes. On average, the cross success was 8.42% when the varieties of B. rapa used as female parents in contrast to 2.88% when B. rapa used a pollen parents. Among the four concentrations (25, 50, 75 and 100 ppm) of GA₃, 75 ppm gave highest response for different crossability characters in both way cross directions. The hybrids contained 19 somatic chromosomes which were the sum of the gametic chromosome number of B. rapa and B. oleracea. Of the two methods, followed to induce chromosome doubling in the adult plants, the Modified Injection Method was found more effective than the Cotton Plug Method. Among different concentration of colchinine 0.20% gave the highest success (66.67%) of chromosome doubling in the hybrids. All the colchiploid (C₁) plants contained 38 chromosomes in their somatic cells which were the sum of the somatic chromosomes of both species. The genomes of resynthesized lines were also identified through Brassica genome specific SSR markers. The presence of markers for both A and C genome was detected in resynthesized lines suggesting that their genomic constitution was AACC.

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• Colchicine-induced polyploidy as a strategy for genetic enhancement of Brassica rapa var. chinensis
  Masood Kausar, Sajjad Ali Shah, Iftikhar jan, Adil Khan, Syeda Rahmat bibi, Hina Ali, Musaab Dauelbait, Esmael M. Alyami, Mona Alsolami, Abdel-Rhman Z. Gaafar
  BMC Plant Biology.2026;[Epub]     CrossRef
• Introgression of a Stable Locus for White Rust Resistance Harboring Putative NBS-LRR Class R Genes in Backcross Progeny of Allohexaploid Brassica
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• Fertility, genome stability, and homozygosity in a diverse set of resynthesized rapeseed lines
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Genome sequencing has been going on major medicinal plants, including Platycodon grandiflorus, which is commonly used as a functional food and medicinal resource in Korea. Molecular cytogenetic studies using fluorescence in situ hybridization (FISH) show the chromosomal organization of specific DNA sequences. We analyzed the FISH karyotypes of P. grandiflorus ‘Jangbaek’ and a colchicine-induced tetraploid cultivar ‘Etteumbaek’ using 5S and 45S rDNA probes. As a result, ‘Jangbaek’ had chromosome length ranging from 2.34 ± 0.13 to 3.99 ± 0.197 μm with its karyotypic formula of 2n = 2x = 18 = 16m + 2sm (two satellites) whereas ‘Etteumbaek’ had chromosome length of 2.37 ± 0.08 to 4.20 ± 0.16 μm and a karyotypic formula of 2n = 4x = 36 = 24m + 12sm (four satellites). A pair of 5S rDNA signals observed interstitially in chromosome 3 and the co-localization of 5S and 45S rDNA signals occupying the nucleolar-organizing region (NOR) of chromosome 6 was observed in the diploid cultivar ‘Jangbaek’. Doubling of both signals co-localized in the NOR of chromosome 6 were observed in the colchicine induced tetraploid cultivar. However, the tetraploid revealed a modified positioning of 5S rDNA signals on chromosome 3 interstitially, with observable vague dispersed signals in one chromosome of chromosomes 1 and 5. This result will be useful for further breeding program and chromosomal backbone for the Platycodon genome analysis.

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• Cytogenomic evaluation of regenerated Aralia elata using PLOP-FISH and flow cytometry
  Eliazar Alumbro Peniton, Hong Thi Nguyen, Nomar Espinosa Waminal, Tae-Jin Yang, Hyun Hee Kim
  Scientific Reports.2024;[Epub]     CrossRef
• Cell cycle synchronization in Panax ginseng roots for cytogenomics research
  Eliazar Alumbro Peniton, Nomar Espinosa Waminal, Tae-Jin Yang, Hyun Hee Kim
  Horticulture, Environment, and Biotechnology.2022; 63(1): 137.     CrossRef