[The structural characteristics and symplastic transport function of the Ectodesmata-like of root cap tissue in Zea mays].

The ultrastructure and symplastic transport function of Ectodesmata-like (ED-like) of the root cap cells of Zea mays, during the detaching stage, were reported by using fluorescence and electron microscopy. It was described the process that plasmodesmata (PD) were gradually stretched and changed into ED-like. It was discovered that the diameter of appressed endoplasmic reticulum (AER) in PD became thinner while the ED-like still remained some structures of PD. By using fluorescence probe incubating, 457Da Lucifer Yellow (LYCH) which was impermeable to the membrane, could enter the root cap cells through ED-like. The results proved that ED-like still retained physiological activity and kept the symplastic transport function during a period time. When the root tissues were pre-treated by cytochalasin D (CD), Phalloidin and 2,3-butanedione, 2-monoxime (BDM) and then combined with fluorescence probe detecting, the results showed that F-actin and myosin might take part in the regulation of the substance translocation of the ED-like.