文档介绍：杜仲胶在杜仲叶发育过程中的含量变化研究摘要: 综合应用石蜡切片法和实验室提胶法研究了杜仲胶在杜仲叶生长发育过程中的变化规律, 探讨了杜仲叶结构发育与杜仲胶积累的关系。结果表明, 杜仲叶含胶细胞在一年中的形成积累具有一定的独立性。从叶片展开到叶片停止生长仅有1个月时间, 叶片大小在生长30 d以后基本保持恒定。随着叶片栅栏组织、海绵组织等叶肉细胞的分化发育,叶片内含胶细胞也在不断地形成积累; 叶片各结构生长停止后, 含胶细胞仍继续增加和生长, 叶片含胶率总体上呈增加的趋势。由于杜仲叶片内杜仲胶分泌、积累与叶片生命周期在 1 年中同步,使在将近黄落的11月份叶片含胶率较高, 1 %。关键词:杜仲;叶片发育;杜仲胶;含量 abstract : by means of paraffin sectioning and gutta-percha ru bber extracting method , the cha nge rule of gutta-percha durin g the development of mia u lmoides oliver and the correlatio n between gutta-percha accumul ation and anizational structure was investigated. th e results showed that the forma tion and accumulation of rubbe r cell in one year had certain in dependence. it was only one mon th from the leaf blade growing to the leaf blade stopping; the size of leaf blade maintained c onstant after growing for 30 d. the f ormation and accumulation of r ubber cell in leaf blade contin ued with the differentiation a nd development of palisade par enchyma and spongy parenchyma in leaf blade. however, the rub ber cell still increased and gr ew after the growth of various characters of leaf blade had st opped and the content of rubber in leaf blade presented an incr easing tendency as a whole. the content of gutta-percha reache d the highest( 1 %) in novembe r due to accumulation of a whole y ear. key words: mia ulmoides oliver ; leaf growth ; gutta-percha ; content 杜仲(mia ulmoides oliver )又名思仲、丝连皮、丝***、丝绵树、木绵树,是多年生落叶乔木, 自成 1属1科, 即杜仲科( miaceae ) 杜仲属(e ucommia oliver ) [1 ] ,杜仲树高可达15~20 m, 是地质史上第三纪冰川运动残留下来的古生物树种[ 2-4 ], 因其体内多个部位均含有胶状成分, 故折断面都有银白色的细丝出现[5 ] ,这是识别杜仲的最重要特征。杜仲是国家珍稀濒危二级保护植物,为中国特有的优良经济林树种[6 ] 。传统上杜仲以皮入药,中药里的杜仲指的就是杜仲皮[7 ] ,古代把杜仲视为中药的上品,具有许多医疗功效[8,9 ] ;现代科学研究证实了杜仲叶及杜仲皮具有补肝肾、强筋骨、安胎、降压等功效[ 10 , 11 ], 所以杜仲为名贵的中药材。研究表明, 在杜仲的叶、根、树皮、种子和果皮等部位中含有的胶状成分是一种白色的胶丝物质, 又称为杜仲胶, 这是一种野生的天然高分子资源, 其化学成分是反-1 , 4-聚异戊二烯; 物理性质方面, 其在室温时是皮革状的坚韧物质, 纯胶无色, 商品胶则带有各种颜色。纯胶在10 ℃时结晶, 40~50 ℃开始表现有弹性、易伸长,到100 ℃时软化,具有可塑性,冷却后可恢复原来的性质[12-14 ] 。因此可以用于开发热塑性功能材料、热弹性形状记忆材料, 特别是可以开发研制杜仲胶