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

摘要：

膜苞鸢尾（Iris scariosa）种子存在休眠。通过萌发抑制物测定、胚培养、低温层积、赤霉素处理等方式对其休眠及萌发特性进行研究，结果表明：膜苞鸢尾种皮及胚乳均透水性良好，最适萌发温度为15/25℃，对光照要求不严；胚无休眠特性，种皮与珠孔端处胚乳对种子萌发有机械束缚；种皮与胚乳中分别含有水和醇溶性抑制物；低温层积能有效打破膜苞鸢尾种子休眠，沙藏40 d萌发效果最佳；NaOH处理浓度低于10%对种子萌发影响不大，但从10%开始随浓度增高萌发率明显降低，而不同浓度赤霉素处理对种子萌发无影响。

关键词: 膜苞鸢尾, 种子萌发, 低温层积, 休眠