不同钾离子浓度处理影响烟草DNA甲基化变化的MSAP分析

MSAP Analysis of DNA Methylation Variation for Flue-cured Tobacco Treated with Different Potassium Concentration

烟叶钾含量是评定烤烟品质的重要指标之一,它与烟叶的燃烧性、降低危害物质、增强烟叶的香吃味等密切相关。本试验以钾元素富集能力较强的烟草为材料,采用不同的钾离子浓度处理烟苗,研究不同钾离子浓度对DNA甲基化变化的影响,试验结果表明,0、15 mmol/L、30 mmol/L、45 mmol/L和60 mmol/L硝酸钾浓度处理烟苗的总甲基化比例为33.26%、32.82%、29.20%、28.94%和27.43%,全甲基化比率为22.45%、22.17%、19.47%、19.43%和17.71%。随着钾离子处理浓度的增高,甲基化条带比率、全甲基化条带百分比均逐渐降低,DNA甲基化的变化可能是烤烟幼苗调控基因表达响应钾胁迫的方式之一。

The potassium content in leaves is one of the most important indexes to evaluate the quality of flue-cured tobacco, which is closely related to the combustibility of tobacco leaves, reducing the harmful substances and enhancing the flavor of tobacco. In this experiment, the potassium-enriched flue-cured tobacco cultivar was selected and treated with different concentration of potassium nitrate. The effects of different potassium concentration on variation of DNA methylation were tested. As a result, with the increase of potassium nitrate for 0 to 60 mmol/L（0, 15 mmol/L, 30 mmol/L, 45 mmol/L and 60 mmol/L）, the total methylation ratio were33.26%、32.82%、29.20%、28.94% and 27.43%, respectively. The full metheylation percentage were 22.45%、22.17%、19.47%、19.43% and 17.71%, individually. With the increase of potassium nitrate concentration, the ratio of methylation band and percentage of full methylation bands were gradually decreased, which may imply that changes of DNA methylation may beone of the way to regulate gene expression in response to potassium stress.