关键词: 膜苞鸢尾, 种子萌发, 低温层积, 休眠

Abstract:

The dormancy mechanism and the germination characteristics of Iris scariosa were studied using different treatments such as germination inhibitor determination, embryo culture, low temperature stratification and gibberellin application. The results showed that both the endosperm and the testa of Iris scariosa had good water permeability. The optimum germination temperature was 15/25 (night/day) Celsius degree. Light had no effect on germination. The seed was a low dormancy seed, and the seed embryo had no dormancy characteristics. Both the testa and the endosperm at the micropylar end had mechanical constraint affecting seeds germination. Moreover, both the testa and the endosperm contained ethanol soluble materials inhibiting seed germination. The low temperature stratification can break the dormancy of Iris scariosa Willd.ex Link seed, and the optimization effect of stratification on germination was to store the seeds in sand for 40 days, The concentrations of NaOH had little effect on seed germination when it was less than 10%. Starting from 10%,the higher concentration of NaOH, the lower germination rate of the seeds was. There was no effect on seed germination with different concentration of gibberellin application.

Key words: Iris scariosa, Seeds germination, Low temperature stratification, Dormancy