Publications by authors named "Katsuhiko Sumitomo"

Chrysanthemum (Chrysanthemum morifolium Ramat.) is a short-day plant, and flowering is stimulated when the photoperiod is shorter than a variety-specific threshold (critical day length). In Japan, summer-to-autumn-flowering cultivars (SA-cvs.

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In the long history of human relations with flowering cherry trees in Japan, 'Somei-Yoshino' occupies an exceptional position among a variety of flowering trees: it is a self-incompatible interspecific hybrid but has been enthusiastically planted by grafting throughout Japan, due most likely to its flamboyant appearance upon full bloom. Thus, 'Somei-Yoshino' gives us a rare opportunity to trace and investigate the occurrence and distribution of somatic mutations within a single plant species through analysis of the genomes of the clonally propagated trees grown under a variety of geographical and artificial environments. In the studies presented here, a total of 46 samples of 'Somei-Yoshino' trees were collected and their genomes were analysed.

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White rust caused by is one of the most serious diseases of chrysanthemum ( × ). In this study, we report the DNA markers associated with resistance against via a simple approach using the genome of a wild diploid relative, . First, we identified the important region of the genome in the resistant cultivar "Ariesu" via a genome-wide association study.

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Chrysanthemums are one of the most industrially important cut flowers worldwide. However, their segmental allopolyploidy and self-incompatibility have prevented the application of genetic analysis and modern breeding strategies. We thus developed a model strain, Gojo-0 (Chrysanthemum seticuspe), which is a diploid and self-compatible pure line.

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The use of DNA markers has revolutionized selection in crop breeding by linkage mapping and QTL analysis, but major problems still remain for polyploid species where marker-assisted selection lags behind the situation in diploids because of its high genome complexity. To overcome the complex genetic mode in the polyploids, we investigated the development of a strategy of genome-wide association study (GWAS) using single-dose SNPs, which simplify the segregation patterns associated polyploids, with respect to the development of DNA markers. In addition, we employed biparental populations for the GWAS, wherein the SNP allele frequency could be predicted.

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Article Synopsis
  • * Chrysanthemum morifolium faces challenges in genetic analysis and breeding due to its autohexaploid nature and high genome heterogeneity, prompting the development of a more manageable model strain called Gojo-0 from the diploid C. seticuspe.
  • * Gojo-0 is advantageous for genetic studies and breeding as it allows for the isolation of mutants and easier genome analysis, enabling further research and genetic improvements in chrysanthemum cultivars.
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Chrysanthemums require continuous short-days (SD) for anthesis. FTL3 (FLOWERING LOCUS T-like 3), a floral promoter expressed in chrysanthemum leaf, forms a complex with its interacting partner FDL1 to induce floral meristem identity gene AFL1. We explored the FTL3 induction mechanism during SD repeats in Chrysanthemum seticuspe.

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Cultivated chrysanthemum (Chrysanthemum morifolium Ramat.) is one of the most economically important ornamental crops grown worldwide. It has a complex hexaploid genome (2n = 6x = 54) and large genome size.

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Background: Chlorophylls (Chls) are magnesium-containing tetrapyrrole macromolecules responsible for the green color in plants. The Chl metabolic pathway has been intensively studied and nearly all the enzymes involved in the pathway have been identified and characterized. Synthesis and activity of these enzymes are tightly regulated in tissue- and developmental stage-specific manners.

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Photoperiodic floral induction has had a significant impact on the agricultural and horticultural industries. Changes in day length are perceived in leaves, which synthesize systemic flowering inducers (florigens) and inhibitors (antiflorigens) that determine floral initiation at the shoot apex. Recently, FLOWERING LOCUS T (FT) was found to be a florigen; however, the identity of the corresponding antiflorigen remains to be elucidated.

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Flowering time of the short-day plant Chrysanthemum morifolium is largely dependent upon daylength, but it is also distinctly influenced by other environmental factors. Flowering is delayed by summer heat. Here, the underlying basis for this phenomenon was investigated.

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Chrysanthemum (Chrysanthemum morifolium) is a short-day plant, which flowers when the night length is longer than a critical minimum. Flowering is effectively inhibited when the required long-night phase is interrupted by a short period of exposure to red light (night break; NB). The reversal of this inhibition by subsequent exposure to far-red (FR) light indicates the involvement of phytochromes in the flowering response.

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Chrysanthemum is a typical short-day (SD) plant that responds to shortening daylength during the transition from the vegetative to the reproductive phase. FLOWERING LOCUS T (FT)/Heading date 3a (Hd3a) plays a pivotal role in the induction of phase transition and is proposed to encode a florigen. Three FT-like genes were isolated from Chrysanthemum seticuspe (Maxim.

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Temperature plays a significant role in the annual cycling between growth and dormancy of the herbaceous perennial chrysanthemum (Chrysanthemum morifolium Ramat.). After exposure to high summer temperatures, cool temperature triggers dormancy.

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The white petals of chrysanthemum (Chrysanthemum morifolium Ramat.) are believed to contain a factor that inhibits the accumulation of carotenoids. To find this factor, we performed polymerase chain reaction-Select subtraction screening and obtained a clone expressed differentially in white and yellow petals.

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Nineteen carotenoids were identified in extracts of petals of orange- and yellow-flowered cultivars of calendula (Calendula officinalis L.). Ten carotenoids were unique to orange-flowered cultivars.

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