秋水仙素离体诱导分蘖洋葱茎尖多倍体的研究

In Vitro Induction of Polyploid by Colchicine in Shoot Tips of Tillered Onion

以分蘖洋葱品系Z-018的茎尖外植体为材料,通过不同浓度秋水仙素及处理时间对分蘖洋葱茎尖细胞染色体的诱导,以获得倍性变异的分蘖洋葱材料。结果表明:当秋水仙素质量分数为0.01%,处理4 d时,多倍体的诱导率最高,可达42.22%。得到的变异植株与正常二倍体植株相比,表现为生长缓慢,叶片、假茎及根系粗壮,叶片的气孔保卫细胞变大,密度减小。进一步对根尖染色体数目进行鉴定及利用流式细胞仪分析测定DNA含量,在149株变异株中,获得倍性变异株117株,其中四倍体材料81株,占变异总数的54.36%。

In this experiment, shoot tip explants of tillered onion strain Z-018 were used as materi- als, which were inoculated on solid medium added with inducer in vitro induced, and chromosome of shoot tips of tillered onion was induced at different concentration and treatment duration, in order to obtain ploidy variation of tillered onion materials. The results showed that when colchicine concen- tration was 0. 01% with the treatment of 4 days, polyploid induction rate was the highest, up to 42. 22%. Compared with normal diploid plants, variant plants showed slow growth, leaf, false stem and roots were thicker, stomatal guard cells of leaves became larger, and density decreased. Further identification of root tip chromosome number and flow cytometry analysis of DNA content were con- ducted, and in 149 strains of variant strains, 117 strains were obtained, of which 81 were tetraploid materials, accounting for 54.36% of the total variation.