Objective To examine the effects of rare-earth elements on the seedling growth of Dendro-bium candidum. Methods The seedlings were tested as the explants and cultured on 1/2 MS culture medium with extract from banana at the concentration of 20% and different portions of three kinds of rare earth elements. Results Lanthanum (La), in the three rara-earth elements, has a remarkable effect on the seedlings including increment weight, chlorophyll b, total chlorophyll, and content of Dendrobium polysaccharide. Bu...