[Objective] The obtained clear AFLP fingerprint of Chinese cabbage provided basis for studies on the molecular markers of Chinese cabbage cultivars and the phylogenetic relationship among Chinese cabbage cultivars. [Method] With the test materials of leaves of Chinese cabbages, the high-quality total DNA from leaves of Chinese cabbages was extracted by the modified CTAB method. DNA restriction-ligase reaction, pre-amplification and selective amplification were optimized, and the AFLP silver-staining reaction system for Chinese cabbage was established. [Result] The quality of DNA template influenced restriction enzyme digestion and the subsequent ligase amplification reaction, while the modified CTAB extraction method could be used in AFLP analysis of Chinese cabbage to obtain a clear AFLP fingerprint. The optimum conditions for restriction enzyme digestion of genomic DNA from Chinese cabbage were as follows: 150 g DNA template, 12.5 μl reaction volume, 1.25 U Eco R Ⅰ, 1.25 U Mse Ⅰ and 5×Reaction Buffer with 4 h at 37 ℃. The ligation reaction with 2.5 h at 20 ℃ was the optimum condition. Six pairs of primers including E-AAC/M-CAG, E-AAG/M-CAC, E-ACA/M-CTG, E-ACT/M-CAC, E-ACT/M-CTT and E-ACT/M-CTC all had its own stable and clear patterns. [Conclusion] With abundant bands and high polymorphism, AFLP selective amplification is an efficient molecular marker for genomic polymorphism of Chinese cabbage.
