Abstract：A target fragment which contain two CCGG sites was cloned from the first coding region of S-locus receptor kinase gene (SRK) of Brassica oleracea with typical self-incompatibility (SI). Then the method combining methylation-sensitive restriction endonucleases with PCR (MS-RE-PCR) was used to analysis primarily the methylation of the specific DNA fragment of SRK gene coding region, that is, genomic DNA (gDNA) extracted from stigma papilla and anther and their PCR amplification products were digested and electrophored interlacedly and combindly. The restriction endonucleases were MspⅠand HpaⅡ，whose methylation-sensitivity were different. When using the same specific primer, the target bands could be got by using gDNA as template, and all target bands could also be digested completely by MspⅠ/HpaⅡ producing the expected smaller bands, but there was no specific PCR amplification products by using gDNA digested by MspⅠ/HpaⅡ as template. These results indicated that SRK gene in anther of SI B. oleracea may be not blocked by DNA methylation.
