[The influence of abscisic acid treatment on desiccation tolerance in Dendrobium candidum protocorm-like bodies].

Effect of ABA on desiccation tolerance in the protocorm-like bodies (PLBs) of D. candidum was studied. The best result was obtained while ABA precultured at 5 micromol/L for 24 h (Fig.2). PLBs vitality rate was 10 times of the control after 2 h desiccation (Table 1). Detection of cytoplasmic osmoticums showed that ABA preculture could not induce the accumulations of soluble sugar, proline, etc (Tables 3, 4 and 7). But the content of soluble polysaccharide rose conspicuously (Table 5). So we think that the accumulation of soluble polysaccharide may play an important role in desiccation tolerance induced by ABA preculture.