4种大花蕙兰与国兰杂交F_1代核型分析

Study on Karyotype Analysis of Four Species of Hybrid F_1 Generation between Cymbidium hybridiumand Chinese Cymbidium

首次报道4种大花蕙兰与国兰杂交后代染色体形态与核型。结果如下:绿宝石×春剑(Cym.LovelyValley‘Evergreen’×Cym.Longibracteatum)后代2n=3x=45m+15sm,核不对称系数为59.75%,2B型;天使×蕙兰(Cym.KLR565×Cym.faberi)后代2n=3x=42m+18sm,核不对称系数为59.33%,2B型;夏绿×春剑(Cym.SummerQueen×Cym.Longibracteatum)后代2n=2x=30m+10sm,核不对称系数为58.58%,2B型;圣蕾芬×春剑(Cym.SaintRaphin×Cym.Longibracteatum)后代2n=2x=34m+6sm,核不对称系数为57.15%,2B型;结合兰属植物若干稳定特化的形态学特征,讨论了兰属植物的核型进化。

Four Species of Hybrid F 1 Generation between Cymbidium hybridiumand Chinese Cymbidiumare karyologically analyzed. Their karyotype formula and index of karyotypic asymmetry （As.k） are presented as follows： Cym. Lovely Valley ＇ Evergreen ＇ × Cym. Longibracteatum, 2n=3x=45m＋15sm, As.k=59.75%; Cym. KLR565×Cym. faberi, 2n=3x=42m＋18sm, As.k=59.33%; Cym. Summer Queen×Cym. Longibracteatum 2n= 2x=30m＋10sm, As. k=58.58%; Cym. Saint Raphin×Cym. Longibracteatum 2n=2x=34m＋6sm, As.k=57.15%. According to Stebbins classification of karyotypic asymmetry, all of the karyotypes belong to ＂ 2B ＂ . Moreover, with some stably specialized traits in morphology, the evolution of karyotypes in Cymbidium was also discussed.