肉桂芽茎中黏液细胞与油细胞空间分布与分化发育OA

In order to investigate spatial distributions and developmental processes of mucilage cells and oil cells in Cinnamomum cassia,as well as their morphological characteristics and secretory product accumulations at different developmental stages,young shoot stems from three-year-old to four-year-old C.cassia plants were used as experimental materials.Multiple histochemical staining methods combined with light microscopy were employed to analyze spatial distributions and developmental processes of two kinds of cells,and image analysis software was used for quantitative analysis on cell density,cell area and integrated optical density(IOD).Re-sults showed that mucilage cells initiated differentiation in regions of first leaf primordium and first bud primor-dium near growth points,and oil cells initiated differentiation in region of second leaf primordium.From pith to inner edge of cortex,number of mucilage cells gradually decreased,while their areas gradually increased and became mature.From phloem to pith,number of oil cells gradually decreased,while their areas gradually in-creased and became mature.Two secretory cells underwent initial stage,early vacuolization stage,middle vacu-olization stage,late vacuolization stage and mature stage.Oil cells exhibited disintegration stage and ultimately formed typical oil sac structures.Mucilage cells mainly stored polysaccharides,and oil cells primarily stored es-sential oils.Polysaccharides secretion in mucilage cells began at initial stage and accumulation peaked at late vacuolization stage.Essential oils in oil cells accumulated rapidly during middle and late vacuolization stages,which accumulation peaked at mature stage.Quantitative analysis on cell area and IOD were consistent with mi-croscopic observations of tissue sections.