Using the cotyledon、cotyledon node、hypocotyl and leaf of explants of Zajiaohuanghou of its germ-free seeding in the culture mediums with 6-BA and 2,4-D added at different combination concentrations.The results showed that the cotyledon、cotyledon node、hypocotyl and leaf differed markedly in the differentiations of their callus.cotyledon nodecotyledonhypocotylleaf.They all had higher inductivity of callus on the culture medium with 6-BA and 2,4-D,but adventitious buds were only induced by cotyledon and cotyledon node.It was necessary that the culture medium with 6-BA.The best culture medium was MS+ 6-BA 1.0 mg/L+2,4-D 0.1 mg/L.The effect was better that the adventitious buds were induced by cotyledon and cotyledon node,and cotyledon node had the highest inductivity of adventitious buds on the culture medium.