DNA METHYLATION PATTERN IN THE PROCESS OF FLORAL BUD DIFFERENTIATION IN RADISH (RAPHANUS SATIVUS L.) WITH MSAP ANALYSIS

The level and pattern of cytosine methylation during floral bud differentiation was evaluated in radish (Raphanus sativus L.). A methylation-sensitive amplified poly¬morphism (MSAP) fingerprinting technique, relying on a pair of isoschizomers that differ in their sensitivity to methylation of recognition sites, was utilized. It was found that in radish the level of DNA methylation was higher in dry seeds (30.2%) than in leaves; while in the course of floral bud differentiation, the DNA methylation level of leaves exhibited a trend of increase (14.7%<16.6%<16.9%<17.5%). Moreover, both new de novo methylation and demethylation change events were detected with the 18 primer combinations, and the change patterns were complicated. The results clearly demonstrated that a MSAP molecular technique was highly efficient for assessing 5-methylcytosine (5-mC) in the process of floral bud differentiation in radish.