The Developmental Anatomy of Two Kinds of Trichomes in Pogostemon cablin

There were flourishing trichomes on the epidermis of Pogostemon cablin's stem and leaf,and they also have distinct difference in shape and development stage.According to the shape of head,the glandular hairs were divided into capitate and peltate glandular hairs.They all occurred very early and their initial cells came from protoderm,which usually originated from the first and second primordium or 1-2 internode of stem.Their developmental process may be divided into four stages,i.e.primitive cell stage,basal cell stage,stalk cell stage and apical cell stage.The origination of non-glandular hairs was later than that of glandular hairs,but lasting origination time in the former was longer than that in the latter.Non-glandular hairs usually started to occur in the secondary immature leaf,and also continue to occur in mature leaves and stems.After initial cells formed,they began to periclinal division to develop into basal cell and head cell.Head cell also began to periclinal division(once or more) to develop into the composing cells of non-glandular hairs.