Abstract: The ultrastructural distribution of acid phosphatase (ACPase) alkaline phosphatase (ALPase) and the changes of their activities in the laminar hair cells of Bresenia shreberi Geml. were studied by means of lead phosphate preciptation method during their development. The ACPase activity became detactable at the stage of mucilage secretion of the head cell, which was located at endoplasmic reticulum (Er),cuticle (Cu) and tonoplast (Tp) of the head cell, and nuclear membrane (NM), plasmodesmata (P1) and wall ingrowths (WI) of the stalk cell, and WI and plasmolemma of basal cell. ALPase activity showed its first appearance at the mitochondria(Mi) of the basal cell at the stage of head cell formation. At the stage of head cell secretion, ALPase activity was located at Er, Cu, Mi of head cell, and NM, Go, Er, WI and P1 of stalk cell. ALPase activity at Mi of basal cell was most intensive. The results indicated that ACPase and ALPase possessed the function of promoting cell differentiation and material transfer in the process of hair cell development and that the material for synthesizing mucilage in head cell was provided by the basal cells and the parenchyma cells nearby.

Key words: Acid phosphatase, Alkaline phosphatase, Cytochemical electron microscopy , Glandular hair, Bresenia shreberi