翅果油树休眠芽和种子的试管萌发

Studies on germination of dormant bud and seed of Elaeagnus mollis under tisssue culturing

目的 为了扩大珍稀濒危植物翅果油树组织培养的取材范围和研究其种子休眠的原因。方法 以翅果油树一年生枝条的休眠芽 (分别于 10 ,11,12 ,1,2 ,3,月份取材 )和当年生种子为材料 ,采用 MS为基本培养基 ,附加 6 -BA、NAA、GA3 等外源激素进行试管苗萌发研究。结果 1.休眠芽的萌发率表现为从秋季到冬季逐渐下降和从冬季到春季逐渐提高的规律性变化。其中以 3月份取材最佳 ,休眠芽可萌发为小苗。2 .对种子进行试管内和试管外萌发研究 ,表明翅果油树种子休眠的原因有 :中果皮坚硬 ,种皮革质化 ,透水透气性差 ;中果皮和种皮内有抑制物质存在 ;种仁营养丰富 ,易引起土壤、空气中微生物的繁殖而烂种 ;此外 ,裸露的种仁在试管中的萌发率高达 70 % ,可发育为无菌苗。结论 3月份取材的休眠芽和种仁无菌萌发的实生苗可为组织培养提供新的材料来源。

Object To study the factors causing the dormancy of seed and to broaden the scope in the choice of explant for the tissue culture of the rare and near extinct plant Elaeagnus mollis Diels.Methods Dormant buds from one-year old branch collected each month from Autumn to next Spring, and seed of the very year were selected and cultured on basic media with the addition of 6-BA, NAA and GA 3 Results The germination rate of dormant bud follows the regular order of the months when it was taken. Those taken in Autumn declined every month until next Spring, and the nrevived monthly with those taken in March showing the most prosperous germination.The dormant bud can germinate into shoots. When seed was cultured, there are several factors leading to its dormancy: hardness of the mesocarp, keratinization of periderm, refractory to water permeation and the presence of certain inhibitory subtances. Seed kernal is rich in nutrition, but susceptible to bacterial infection leading to its decay. But the germination rate was well over 70% which can be cultured to give bacteria free shoots. Conclusion Both dormant buds obtained in March and bacteria free shoots germinated from naked kernal can be used as new sources for the tissue culture of E mollis .