组织培养导致的草莓DNA甲基化变异

以草莓品种‘丰香’和‘全明星’为材料，用甲基化敏感扩增多态性（MSAP）技术研究组织培养对草莓DNA甲基化的影响。结果表明，与普通苗相比，组织培养导致草莓试管苗的DNA甲基化水平下降，甲基化模式的变异以去甲基化为主。组织培养导致的DNA甲基化变异不稳定，在田间无性繁殖过程中，试管苗的无性繁殖后代DNA甲基化水平逐渐升高，仅部分变异的甲基化模式能够在试管苗的无性繁殖后代中稳定传递。两个品种之间，纽织培养对DNA甲基化变异程度的影响不同。

DNA Methylation Variation Induced by Tissue Culture in Fragaria ananassa Duch.

Methylation sensitive amplified polymorphism （MSAP） was used to assess the DNA methylation variation in Fragaria ananassa cvs. ＇Toyonoka＇ and ＇Allstar＇ during the process of tissue culture. The results showed that the methylation levels were lower in micropropagated plants than in conventionally propagated runner plants （control）, and that demethylation was the main DNA methylation alteration pattern. However, the variation induced by tissue culture was not constant. The methylation levels in the asexual descendants of the micropropagated plants increased gradually in the field. In the asexual reproduction descendants, only part of the variation in the methylation pattern which was induced by tissue culture could be inherited from micropropagated plants. The effect of tissue culture on the variation level of methylation was different between the two strawberry cultivars. There might be correlation between the phenotypic characteristics of strawberry plants derived from in vitro and the DNA methylation variation.