秋水仙素处理离体叶片获得皇家嘎拉苹果四倍体植株

采用皇家嘎拉苹果（Malus domestica Borkh．）离体新梢叶片作为外植体，研究了不同浓度的秋水仙素长时间处理（5 d）诱导四倍体的效率。结果表明，以不定芽再生培养基附加25 mg／L秋水仙素效果最好，最高在36．7％的叶片外植体上获得了四倍体植株。高浓度（75～200　mg／L）秋水仙素处理严重抑制组织的再生。采用流式细胞技术测定出诱变植株的细胞核DNA含量比对照高出一倍，确定了植株为四倍体。四倍体植株不仅在遗传上而且在外观形态上也明显区别于二倍体。四倍体植株已移栽于大田，并进行了嫁接育苗和大树高接。

Regeneration of Tetraploid Plants of Royal Gala Apple VarietyFrom in vitro Leave Treated with Colchicine

As a part of the program for improving the fruit characteristics of Royal Gala apple variety Malus domestica Borkh． in vitro cultured leaflet explants were treated on the shoot regeneration media supplemented with 0～200 mg／L colchicine for 5 days． Results shown that the tetraploid plants could be obtained from explants only on the medium with 25 mg／L colchicine． The efficiency was 36．7％． High concentration of colchicine inhibited regeneration and killed leaf explants． Flow cytometry was used for ploidy determination． The tetraploid plants were distinguishable from the diploid on morphlogical as well as cytogenetic grounds． All plants were transplanted into field and grafted on the rootstocks to evaluate the agronomic characters．