Recovery of Cryopreserved Buds of Chinese Yam (Dioscorea Polystachya Turcz.) Observed under Scanning Electron Microscope (Sem)

Abstract

Early development of cryopreserved Chinese yams’ (Dioscorea polystachya Turcz) explants were studied under scanning electron microscope (SEM). A combination of vitrification and droplet protocol was implemented with 3 weeks cold acclimation in an alternating temperature of 28°Cday/5°C night and 15% sucrose in the pre-culture medium. Survival in the form of shoot and swelling at the axil or at the near apex of original leaf bud was observed at 3 days after re-culture (rewarming). At 7 days after re-culture, development of new axillary shoot, elongation and enlargement of the surviving green structures as well as addition of new tissues to the previously developed callus at terminal bud were observed. Shoot differentiation from green structures was observed at 16 days after re-culture.