Cordero C D A, Baldwin J G
J Nematol. 1990 Jul;22(3):356-61.
Fine structure of the body wall cuticle of Heterodera schachtii is compared with respect to age and body region of the female. The cuticle is more complex than previously reported. In newly molted females only layers A, B, and C are present, but 4 weeks after the final molt a thin D layer is present between the midbody and base of the cone. This D layer is absent in the cone of H. schachtii, regardless of age. As females age, an additional layer E is produced and includes zones E and E. Zone El apparently is unique to H. schachtii, whereas E is likely to be homologous with a similar layer in Atalodera. In the cone of old females (ca. 8 weeks after the final molt) of H. schachtii, the two zones become irregular in shape and comprise bullae. The presence of a thin D layer in Heterodera strengthens the previous hypothesis of a single ancestor of cyst nematodes.
对甜菜孢囊线虫雌虫体壁角质层的精细结构按年龄和身体部位进行了比较。角质层比之前报道的更为复杂。刚蜕皮的雌虫仅存在A、B和C层，但在最后一次蜕皮4周后，在虫体中部和尾锥基部之间出现了一层薄的D层。无论年龄大小，甜菜孢囊线虫的尾锥中均不存在这一D层。随着雌虫年龄增长，会产生额外的E层，包括E1区和E2区。显然，E1区是甜菜孢囊线虫所特有的，而E2区可能与阿托孢囊线虫的类似层同源。在甜菜孢囊线虫老龄雌虫（最后一次蜕皮约8周后）的尾锥中，这两个区域形状变得不规则并形成大疱。甜菜孢囊线虫中存在薄D层强化了之前关于孢囊线虫有单一祖先的假说。
