Dioecious holocyclic (1)

Dioecious holocyclic cycle (1)

In some species dioecious holocyclic, it is the alate sexupara which effect the migration from the secondary hosts to the primary ones in the summer. When they arrive on the primary hosts, they give birth to sexual morphs, oviparous females and males.

In type 1 dioecious holocyclic species, the alate sexuparae accomplish the return migration to the primary hosts where they give birth to males and oviparous females. The two sexual morphs therefore belong to the same generation. In the case of Pemphigus bursarius illustrated below, which alternates between poplars (primary host) and Asteraceae (on roots) (secondary host), only one generation of fundatrigenia allows an early spring migration towards the Asteraceae. Other species, like Anoecia corni which alternate between dogwood (Cornus) and roots of grasses (Poaceae), produce several generations of fundatrigenia before migration towards the secondary hosts.

Cycle holocycle dioecique