Ogura-CMS in Chinese cabbage (Brassica rapa ssp. pekinensis) causes delayed expression of many nuclear genes

► We have used Ogura-CMS Brassica rapa and its maintainer as plant materials. ► Brassica rapa 300-K oligomeric probe (Br300K) microarray has been used for floral bud transcriptome analysis. ► We found 108 and 62 genes specifically expressed in Ogura-CMS and its maintainer line, respectively. ► Stress-, redox- and auxin-related genes were specifically expressed in Ogura-CMS floral buds. ► The expression of most pollen development-related genes was detected in Ogura-CMS B. rapa, but the timing was delayed.