Abstract: With the inbred line 'Aijiaohuang 97-3-2', 'Huangxinwu 003-27', 'Shanghaiqing 98-4-2' of Chinese cabbage-pak-choi (Brassica campestris L. ssp. chinensis Makino; syn. B. rapa L. ssp. chinensis) ,the inbred line 'Baimanjing 001-24' of turnip [B. campestris L. ssp. rapifera (Matzg.) Sinsk; syn. B. rapa L. ssp. rapifera], the inbred line 'Huangyacai 97-8-6' of Chinese cabbage-pe-tsai(B. campestris L. ssp. pekinensis Olsson; syn. B. rapa L. ssp. pekinensis) and 6 hybrids as experimental material. The relationship between differential gene expression patterns at rosette stage and heterosis of biologic yield component traits in the hybrids and their parents was analyzed by using cDNA-AFLP. Four types of differential gene expression patterns were detected between hybrids and their parents: UNF1 bands were observed only in F1 not in parents; ABF1 bands were observed in both parents but not in F1; UNP bands were observed only in one parent but not in F1 and another parent; DMP bands were observed in one parent and F1 not in another parent. Analysis results showed that ABF1 was significantly correlated with heterosis in leaf number, UNP was significantly correlated with heterosis in height of plant. These results indicated that differential expressed genes might play an important role in heterosis.

Key words: Gene expression, Rape, Chinese cabbage-pak-choi, Chinese cabbage-pe-tsai, Turnip, Brassica campestris, Brassica rapa, Heterosis, cDNA-AFLP