Abstract: MYB transcription factor is involved in plant growth and stress. To understand MYB28 family genes
in rapeseed, expression of the genes after Plasmodiophora brassicae inoculation and salicylic acid（SA）treatment
was studied using susceptible Brassica napus（L.）cv Zhongshuang 11. Expression patterns in different tissues
showed that BnaMYB28 expression levels were higher in stems and seeds than those in roots and leaves. Bna⁃
MYB28 had different responses after P. brassicae inoculation and SA treatment. Among the members, BnaMYB28-1
and BnaMYB28-3 were induced by SA treatment, while BnaMYB28-2 was suppressed. After P. brassicae inocula⁃
tion, BnaMYB28-1 was significantly induced throughout the infection period, althought it was significantly inhibit⁃
ed by adding SA. Expression of BnaMYB28-3 was significantly increased at 7 and 28 d after inoculation. It had no
change during the key cortical infection period（14 d after inoculation）, but was increased significantly under com⁃
bination treatments of pathogen inoculation and SA. It was indicated that, under different treatments, exogenous SA
could positively regulate BnaMYB28-1 and BnaMYB28-3. And BnaMYB28-3 gene might be involved in interac⁃
tion between B. napus and P. brassicae through the SA mediated process.

Key words: Brassica napus L., MYB28, Plasmodiophora brassicae, salicylic acid, expression response