组织培养中大葱染色体倍性变异研究

Study on the variation of Welsh onion chromosome pioidy in vitro culture

采用大葱茎尖分生组织直接成苗及分化丛生苗、茎盘诱导愈伤组织培养再生植株,通过染色体压片,对大葱愈伤组织及幼苗染色体数目变化进行了研究。结果表明,茎尖分生组织培养的幼苗及丛生苗遗传稳定,其染色体未发生倍性变异,均为2n=16;愈伤组织及其再生苗遗传稳定性较差,愈伤组织染色体数变异率为43.4％.其中单倍体占6.7％、三倍体占2.5％、四倍体占10％、五倍体占4.2％、六倍体占3.3％、七倍体占4.2％、八倍体占3.3％、非整倍体占9.2％;愈伤组织分化苗染色体变异率为11.7％,其中单倍体占6.7％,三倍体占1.7％,四倍体占3.3％。

Induced Seedlings and differentiated rank seedlings from the expiant ot the stem tip apex tissue culture of the Welsh onion were obtained directly. Inducing callus from basal plate, the inducing regeneration plant from callus. In this paper, the variation in chromosome ploidy level of Welsh onion during tissue culture was studied by counting chromosome number. The results showed that the number of chromosome, which was from the cultured seedlings of meristem tip and the rank seedlings of meristem tip, was not altered, both the number were 2n=16,the hereditary stability of callus and regeneration plant was poor; and the variation percentage of chromosome in callus was 43.4%, among which haploid accounted for 6.7%, triploid accounted for 2.5%,tetraploid accounted for 10%,pentaploid accounted for 4.2%,hexaploid accounted for 3.3% ,septuploid accounted for 4.2% ,octoploid accounted for 3.3% ,dysploid accounted for 9.2% ;the chromosome variation percentage of differentiation seedlings derived from callus was 11.7% ,among which haploid was 6.7%,triploid accounted for 1.7%,tetraploid was 3.3%.