D.officinale protocorm possessed a great ability of selenium accumulation.The biotransformation of inorganic selenium was terribly high-efficient, and the average was 95.74 percent.

• 铁皮石斛原球茎对硒具有较强的富集作用，其体内硒含量与培养基中无机硒浓度呈显著的正相关，且无机硒的生物转化效率极高，平均达到 95.；74%25。