无毛黄瓜同源四倍体诱导及鉴定

Induction and Identification of Autotetraploid of Glabrous Cucumber

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。

The germinating seeds of glabrous cucumber（ 2n = 2x = 14） were immersed in different concentrations of mixed solution of colchicine（ 0. 2%,0. 4%,0. 8%） and 2% dimethylsulfoxide（ DMSO） for 4hours. The autotetraploid（ 2n = 4x = 28） was obtained successfully by morphological and chromosome identifications. 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,unevener 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.