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Encyclop'Aphid : l'encyclopédie des pucerons


Dioecious holocyclic cycle (2)

In many dioecious holocyclic Aphididae, the oviparous, apterous females are born on the primary host by alate gynopara. The alate males formed on the secondary hosts join the apterous oviparous females.

In type 2 dioecious holocyclic species, the alate gynopara, formed in the summer on the secondary host, migrate to the primary hosts. There they give birth to oviparous females. The alate males, which belong to the same generation as the gynopara, arrive in their turn on the primary hosts to mate with oviparous females. The two sexual morphs are therefore a generation apart.
When the egg hatches, the fundatrix give birth to several generations of fundatrigenia which develop on the primary host in spring. Then alatemigrants leave to colonize the secondary hosts at the end of spring.

This is the case for:

  • The bird cherry oat aphid: Rhopalosiphum padi which alternates between Prunus padus (H I) and a range of Poaceae (HII) 
  • The black bean aphid: Aphis fabae which alternates between various primary hosts (fusain, viburnum, Philadelphus/mock orange) and many secondary hosts (such as Fabaceae, Chenopodiaceae, Solanaceae)
  • The rose-grain aphid: Metopolophium dirhodum which alternates between roses (HI) and diverse Poaceae (HII)
Cycle holocycle dioecique

Illustration with the cycle of Rhopalosiphum padi:

Alternance d'hôtes entre l'hôte primaire (HI) Prunus padus (merisier à grappes) et les hôtes secondaires (HII) graminées cultivées ou sauvages

Rhopalosiphum padi : accouplement
Rhopalosiphum padi : oeufs sur Prunus padus
Rhopalosiphum padi : fondatrice sur Prunus padus

Copulation on Prunus padus

Eggs on Prunus padus

Fundatrix onr Prunus padus

Rhopalosiphum padi : adulte aptère et larves sur blé
Rhopalosiphum padi : adulte ailé

Apterous virginopara and larvae on barley

Winged virginopara on wheat