蓖麻蚕和栗蚕的性染色体研究

STUDIES ON SEX CHROMOSOMES OF THE SILKWORMS,PHILOSAMIA CYNTHIA RICINI AND DICTYOPLOCA JAPONICA

根据在蓖麻蚕（ｐｈｉｌｏｓａｍｉａｃｙｎｔｈｉａｒｉｃｉｎｉ）（♀）和栗蚕（Ｄｉｃｔｙｏｐｌｏｃａｊａｐｏｎｉｃａ）（♀）减数分裂前期所观察到的ｘ（Ｚ）染色体的长度和在全套染色体中的序号以及栗蚕Ｘ染色体的异染色质区域等特征，认为蓖麻蚕的ＸＯ型可能是由ＸＹ型中的Ｙ染色体缺失所致，而栗蚕的Ｘ染色体则可能是由Ｘ和Ｙ染色体融d合为一条而成。

X Chromosomes during the prophase of the cell meiosis in the female sikworms ofPhilosamia cynthia ricini and Dictyoploca japonica were observed.The length,the ordi-nal number of X chromosome in the whole chromosome complement and the character ofheterochromatin region in Dictyoploca japonica's X chromosome suggested that the XOpattern,to female Philosamia cvnthia ricini,was in accord with the second view:whileto female Dictyoploca japonica,it might occur in Y chromosome mergihg into X chromo-Some.