濒危华石斛种子活力测定方法研究

摘要

Dendrobium sinense is an endangered orchid species,which has an important ornamental and medicinal value.The seed is tiny and with an undifferentiated embryo,which making it difficult to store and loss its vitality rapidly.Therefore screening of a fast,accurate methods for detecting seed viability is an important prerequisite to explore the effective preservation method of orchid seeds.An experiment using 2,3,5-triphenyltetrazolium chloride (TTC) and ultraviolet spectrophotometer (UVS) was studied through determined the staining rate and absorbance.The results show that:In the preservation of 1 d to 30 d,the seed viability determined using TTC had an average germination rate of 0.6％ higher than the control,with a change range less than 0.4％,but the operation is complicated.However,the seed viability using UVS had an average germination rate of 0.04％ higher than the control,with a large change range as high as 3.09％,but the experimental operation is simple.Conclusion:The method of TTC could accurately measure the seed viability of D.sinense,but time-consuming,and the method of UVS is simple and rapid,while the accuracy was slightly lower than that of TTC.%华石斛(Dendrobium sinense)为濒危附生兰,具有重要的观赏和药用价值.因其种子细小,仅具未分化的原胚,造成种子难以保存,活力丧失较快.因此,筛选出快速、准确的种子活力检测方法,是兰科种子有效保存方法探讨的重要前提.本试验通过文献查询筛选后,采用四氮(石坐)法(TTC)和紫外分光光度计法(UVS)进行研究,通过测定染色率以及吸光值来反映种子活力,比较其检测方法的可靠性、准确性及操作难易度.结果表明:TTC法测定保存1～30 d的种子活力比实际萌发率高0.60％,变化幅度小,最高仅为0.4％,可信度大,但实验操作较繁琐;UVS法测定的种子活力比实际萌发率高0.04％,但变动幅度相对较大,高达3.09％,精确度相对TTC法较低,但实验操作简单.