无毛黄瓜同源四倍体诱导及鉴定

摘要

The germinating seeds of glabrous cucumber (2n =2x =14)were immersed in different con-centrations of mixed solution of colchicine (0.2%,0.4%,0.8%)and 2% dimethylsulfoxide (DMSO)for 4 hours.The autotetraploid (2n =4x =28)was obtained successfully by morphological and chromosome identifi-cations.The results showed that the treatment with 0.4% colchicine and 2% DMSO for 4 hours had the best induction effect with the chromosome -doubled rate of 14%.Compared with their original diploid plants,the autotetraploid plants had slower growth and development,shorter internode,thicker stem,thicker and shorter petiole,ovary and fruit,larger size of leaves and flowers,lower fruit shape index,larger leaf stomata,uneve-ner tetraploid pollen size and little quantity of quadri -aperture pollens.In addition,their chloroplast number of guard cells was almost 2 times of the original diploid plants.The results would enrich the genetic diversity and germplasm resources of cucumber,provide the theoretical basis for high quality breeding of cucumber and lay a foundation for creating euploid which was associated with the glabrous gene gl.%本研究利用不同浓度（0．2％、0．4％、0．8％）秋水仙碱和2％二甲基亚砜（DMSO）混合溶液浸渍无毛黄瓜（2n ＝2x ＝14）萌动种子4 h，并通过形态学和染色体鉴定相结合的方法，成功获得了其同源四倍体新种质（2n ＝4x ＝28）。结果表明：0．4％秋水仙碱和2％ DMSO 的混合溶液诱变加倍率为14％，诱导效果最好。与原二倍体相比，同源四倍体生长发育缓慢，节间变短，茎变粗；叶柄、子房和果实缩短变粗，叶面积、花器官变大，果形指数减小；保卫细胞叶绿体数几乎为原二倍体的2倍，气孔变大，四倍体花粉大小不均，且存在少量四孔花粉粒。本研究结果丰富了黄瓜遗传多样性，为选育优质黄瓜品种提供理论基础和丰富种质资源，为创制与无毛基因（gl）有关的整倍体奠定了基础。