Developmental Anatomy Study On Vegetative Organs Of Codonopsis Pilosula

Codonopsis pilosula is a kind of traditional Chinese herbal medicines which is widely used in China. Modern pharmacological studies show that the active ingredient of codonopsis play a very important role in treatment of central nervous system, digestive system and blood system diseases, which also process anti-aging and anti-cancer effects. In this study, plant anatomy and histochemical methods have been used to study the structure and the developmental rule of plant, and to study the locations of medicinal ingredients and storage nutrition. The type and the developmental process of the secretory structure laticifers and the relationship between laticifers and medical components of codonopsis pilosula were studied. By clarifying these issues, scientific theory could be provided to identification of medicinal materials, increasing production, improving the content of active ingredients and picking fine varieties. The results of this study are as follows:1. The development and primary structure of codonopsis polosula are as same as other dicotyledons. The primary xylem of root is diarch, of which developmental process contains primary growth and secondary growth. Secondary growth mainly depends on the activity of the vascular cambium and cork cambium. In the root, abundance parenchyma is produced by self cell division and the vascular cambium. Parenchyma is very important to accumulation of medical continent and quality of medicine. The development of stems could be divided into four stages: promeristem, primary meristem, primary structure and secondary growth. The stems of codonopsis which have thin vascular tissue and broad pith are twist, thin and fade in winter, and the vascular cambium could be active just in a short time.2. Lots of laticifers exist in codonopsis, which contain plenty of white latex. The white latex would flow out when it has been cut off. The laticifers with thick cell wall are bigger than other cells around them. It's articulated branched by parts of the common wall become dissolved, and with breakdown of the lateral and transverse walls, the cells are united into a system of compound tubes. Laticifers of codonopsis have the same origin and locations as sieve tubes. It come from primary meristem with it's primary structure and vascular cambium with it's secondary structure. Just a litter Laticifers exist in parenchyma of flower.3. Starch granule accumulated in mature root as reserved substance, which most exist in secondary phloem. Terpene and steroid are the main medical component in codonopsis. In mature roots, terpene and steroid located in phellem cambium, phelloderm, secondary phloem and secondary xylem, and secondary phloem contains the most. In the stem, terpene and steroid also exist in phloem and cortex. The laticifers are considered as an important position of accumulation and transportation for medical components, because a lot of terpene and steroid exist in it. The quantity of laticifers can be used as a medicine quality standard.