Abstract:

The effects of abscisic acid (ABA) on the development of morphology and dormancy of bulblets in vitro of Oriental hybrids‘Siberia’were investigated. The results showed that the primordium was developed into scales only in the dark. While Fluridone, an inhibitor of ABA-synthesis, was applied during in vitro culture, the primordium was developed into scales or leaves. While exogenous ABA applied simultaneously with Fluridone, the effect of Fluridone was nullified. It indicated that the exogenous ABA can inhibite the formation of scal-leaves while endogenous ABA-synthesis was inhibited. Fluridone can reduce the levels of dormancy, and the function can be reversed while adding exogenous ABA. It
suggested that the exogenous ABA can promote the development of dormancy. The dormancy levels of in vitro bulblets cultured at 15, 20 and 25 ℃ will be raised , but the low concentration exogenous ABA had no effect on the bulblets at 15, 20 and 25 ℃ with a low level of dormancy. It speculates that the effect of temperature on the dormancy maybe not play by ABA, an unknown factor , in addition to ABA, still played a key role in dormancy development. There is no relation between the morphology development
and the dormancy levels.

Key words: lily, abscisic acid, fluridone, bulblets in vitro, dormancy development