Abstract: Protocorm2like2bodies of ( PLBs) Dendrobium candidum were desiccated to different water contents by an air-drying method. Samples at different water contents were cryoperserved , and the heat-stable proteins of samples were immunological detected by anti-dehydrin antibody. Water content was based on dry mass , its linear equation was expressed as y = - 0.1208 x + 9.9636. The optimal water content for cryopreservation seemed to be at the range of 0.1 g/ g DM to 0.5 g/ g DM. The amount of heat-stable proteins increased significantly when water content decreased to 1.0 g/ g DM. Results from immunological detection showed that two bands of the heat-stable proteins with respective molecular masses of 28.7 and 34.3 kD were dehydrins , which appeared when water content dropped to 1.0 g/ g DM. Our work revealed that water content might be a key factor for successful cryopreservation as well as for accumulation of dehydrins.

Key words: Dendrobium candidum, Protocorm-like-bodies, Dehydrin, Water content, Cryopreservation