盐肤木虫瘿的结构和发育

STRUCTURE AND DEVELOPMENT OF THE INSECT-GALL OF Rhus chinensis

This paper deals withthe structure and development of insect-gall of Rhus chinensis and changes taken place in the blade tissue in formation of the insect-gall. Our observations suggest that insectgalls be some tumour-like protrusions which developed unnormally because the blade tissue is stimulated by aphis' mouthparts mechani- cally or chemically. Changes which take place in the blade tissue are division and increase in volume of abaxial epidermis cells in formation of the insect-galls. The multiplication of abaxial epidermis cells occurs first in certain position of hollew of abaxial epidermis in immature insect-galls, then they spread wave upon wave. Therefore, all mature insect-galls possess the special abaxial epidermis within their hollow. At the same time, content of chloroplast in palisade and spongy parenchyma decreases obviously, and their intercellular spaces are increased because of lengthen of adaxial and abaxial epidermis cell. Our observations suggest that formation of the insect-galls on the blade of Rhus chinensis may be a series of unnormal development of tissue resulted from only once stimulation of aphis' mouthparts.