がく片が脱離しないデルフィニウム種間雑種の作出(育種・遺伝資源)  [in Japanese] Breeding of Delphinium Interspecific Hybrid without Sepal Abscission(Breeding & Germplasm Resource)  [in Japanese]

デルフィニウムの種間交雑による品種育成を行う中で,STSによる前処理をしなくてもがく片が脱離しない個体を見出した.D.elatum系品種の'マジックフォンテンホワイト'を種子親,D.grandiflorum系品種の'ブルーミラー'('BM')を花粉親として交配を行い,胚珠培養によって植物体を育成した.開花に至った18個体中17個体は,ベラドンナ系に似た草姿,花形であったが,1個体のみ'BM'と同様のわい性の個体('M8-16')が見出された.フローサイトメトリーによる調査の結果,ベラドンナ系に似た個体は3倍体,'M8-16'は4倍体であると推定された.'M8-16'に'BM'を戻し交雑して得られた3個体の内,花持ちが極めて長く,がく片の脱離が見られない個体が1個体見出され,'B10'と名づけた.'B10'の小花を収穫し,花持ち性を調査したところ,'B10'はがく片が脱離せず,その花持ち性は'ベラモーサム'に比べ有意に長いことが明らかとなった.

Interspecific hybrid of Delphinium, in which sepals were not abscised without silver thiosulphate pre-treatment, was raised. Interspecific cross between D.elatum 'Magic Fountains White' and D.grandiflorum 'Blue Mirror' was carried out and 18 interspecific hybrid plants were obtained through ovule culture. Seventeen plants were similar to the plant form and flower shape of the belladonna-type, however, one plant ('M8-16') was a dwarf-type of 'Blue Mirror'. The polyploidy of belladonna-like plants and 'M8-16' were estimated as triploid and tetraploid, respectively, by flow cytometry. Three plants were obtained by backcrossing 'Blue Mirror' to 'M8-16'. One of them ('B10') had very long flowering periods without abscission of sepals. Even sepals of cut florets were not abscised and the vase life of 'B10' was significantly longer than 'Bellamosum'.