洋葱雄性不育分子标记在单倍体鉴定中的应用

Application of Male Sterility Molecular Markers in Identification of Onion Haploid

为有效鉴定和利用洋葱单倍体,以3个洋葱杂交种的未受精花蕾为外植体,通过离体雌核发育途径诱导产生再生植株。利用流式细胞仪对再生植株的倍性进行鉴定,利用DNF-566、RNS-357和AcSKP1标记对再生植株进行纯合性检测。结果表明,源于“阿盾”和“地球”的再生植株在Ms位点的基因型均为纯合的。源于“大宝”的16株再生植株中,有13株在Ms位点的基因型是纯合的,3株是杂合的。说明纯合植株是由大孢子母细胞发育而来,杂合植株可能是由子房壁或其他体细胞发育而来的二倍体。共获得7株二倍体,其中4株为双单倍体。获得的双单倍体,可进一步作为杂交种选育的亲本材料。洋葱Ms位点的分子标记可以作为一种有效的分子标记手段用于洋葱单倍体再生植株与供体杂交种亲本的同源性分析,与流式细胞仪结合起来可以快速准确鉴定双单倍体。

In order to effectively identify and utilize onion haploid,the unfertilized flower buds of three onion hybrid cultivars were used as explants to induce regenerated plants through in vitro gynogenesis.Flow cytometry was used to identify ploidy of regenerated plants,and DNF-566,RNS-357 and AcSKP1 markers were used to detect homozygosity of the regenerated plants.The results showed that the genotypes of plants regenerated from‘ATON’and‘Earth’were homozygous at Ms locus.Of the sixteen regenerated plants of‘TABAO’,thirteen were homozygous at Ms locus and three were heterozygous.These results suggest that homozygous plants are derived from megaspore mother cells,and heterozygous plants may be diploid from ovary wall or other somatic cells.Seven diploids were obtained,of which four were doubledhaploid.The doubled-haploid can be further used as parent material for hybrid breeding.The results further show that the molecular markers of Ms locus in onion can be used as an effective method to analyze the homology between haploid regenerated plants and their donor hybrids.Combining with flow cytometry,the double haploid could be identified quickly and accurately.