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内容記述 |
Gentians are important ornamental plants, and the breeding of gentian cultivars hasbeen actively pursued for decades. However, the genetic resources currently availablefor breeding are limited; therefore, artificial mutagenesis has been applied to createmutants. In this study, we developed an easy and efficient regeneration-mediatedmethod for ion beam mutagenesis in the Japanese cultivated gentian hybrid cultivarAlbireo (Gentiana scabra Å~ G. triflora). Two ion species, carbon (C) and neon (Ne),were tested. The effect of ion beam irradiation on callus formation from leaves wasinitially evaluated. Tissue culture was then continued, adventitious shoots wereinduced from calli, and many regenerated plants were obtained. These plants werecultivated until flowering, and we identified two lines showing a double-floweredphenotype from irradiated leaves with Ne 9Gy and 12Gy among approximately 200individuals. We analyzed one line derived from Ne 9Gy irradiation, referred to asNe9Gy#34, in detail. As a result, AG1, previously known as the gene responsible forthe double-flower phenotype in gentian, was not amplified in the G. scabra allele bygenomic PCR. NGS analysis also indicated that the reads were mapped only to thegenomic region of G. triflora AG1 but not to that of G. scabra, suggesting that thedeletion of G. scabra AG1 caused the double-flowered phenotype. Ne9Gy#34 alsoexhibited increased flower size, suggesting mutations in genes other than AG1, in addition to the AG1 mutation. The regeneration-mediated method described here is apromising approach for inducing gentian mutagenesis and efficiently producing noveltraits in gentian. |
