Abstract: This test was designed to investigate the possibility of Malus zumi micro shoots in vitro rooting in the environmental conditions of both field and green-house. The Malus zumi micro shoots were inoculated in the soil supporting medium and placed respectively in field, greenhouse and incubation chamber for rooting culture, and then the stomata of the plantlet cultured was observed and transplanting test was done. The results show that there were no significant differences in rooting rate among three environmental conditions. The root length of the plantlet cultured in greenhouse and field were significantly higher than that of the plantlet cultured in incubation chamber. The stomata closing function of the plantlets cultured in field and greenhouse were stronger than that of the plantlet cultured in incubation chamber. Being transplanted without hardening the plantlet cultured in field and greenhouse had survival rate of 96.7%, which was significantly higher than that of the plantlet in incubation chamber. In vitro rooting of Malus zumi micro shoots in greenhouse and field environment is feasible and worthy of further study.

Key words: Malus zumi, micro shoot, field, green-house, in vitro rooting, transplanting