利用叶表皮离析、扫描电镜以及常规石蜡切片法对烟台补血草[ Limonium franchetii( Debx.) Kuntze]叶片盐腺的分布和结构特征及其发育过程进行了观察.结果表明:烟台补血草叶片上、下表皮均有盐腺分布,上、下表皮的盐腺密度分别为7.57和8.09 mm-2,同一时期叶片上表皮盐腺密度略小于下表皮.烟台补血草的成熟盐腺是由20个细胞构成的复合结构,其中,中央有4个分泌细胞,每个分泌细胞外侧均伴有1个长方形的毗邻细胞,再向外依次包围着4个内杯状细胞和4个外杯状细胞,靠近叶肉细胞处还有4个收集细胞,收集细胞与盐腺的其他细胞同源；在4个分泌细胞顶端的角质层中央各有1个小孔,称为泌盐孔.烟台补血草盐腺发育过程依次经历原表皮细胞期、2细胞期、4细胞期、8细胞期、16细胞期和20细胞期6个阶段,由1个单独的原表皮细胞发育而成,发育过程中细胞均进行垂周分裂；另外,同一时期的叶片存在盐腺发育不同步的现象.根据观察结果推测烟台补血草主要通过泌盐孔L向外泌盐.%The distribution, structural features and development process of salt gland in leaf of Limonium franchetii ( Debx.) Kuntze were observed by leaf epidermis segregation, SEM and routine paraffin section method. The results show that there are salt glands on both of upper and lower epidermis in leaf of L. franchetii with the density of 7. 57 and 8. 09 mm'2, respectively, and the density of salt glands on upper epidermis is slightly smaller than that on lower epidermis at the same stage. Mature salt gland is a complex structure with twenty cells, in which, there are four secreting cells in the center, every secreting cell is accompanied with a rectangular adjacent cell in the lateral, and outward is bounded by four internal and four external goblet cells successively, and there are four collecting cells close to mesophyll cells. Collecting cells are homologous with other cells in salt glands. There is a small hole on cuticle center on top of all four secreting cells, which is namely salt-secreting hole. The development process of salt gland of L. franchetii successively experiences six development stages including protoderm cell stage, two-cell stage, four-cell stage, eight-cell stage, sixteen-cell stage and twenty-cell stage. The salt gland is developed from a single protoderm cell and cells are all anticlinal division during the development process. Moreover, there is an asynchronous phenomenon on development of salt gland in leaf at the same period. According to observation results, it is conjectured that L. franchetii secrets salt to outside mainly through salt-secreting hole.
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