Interactions between chestnut gall wasp and blight: a new criticality for chestnut

Abstract

The fast spread of Chinese gall wasp (Dryocosmus kuriphilus) represents a new constraint factor for chestnut stands and orchards in Italy. So far, the favourable effect of hypovirulence in Cryphonectria parasitica-Castanea sativa patho-system allowed the development of chestnut cultivation. This situation could be modified by the progressive weakening of the trees caused by intensive attacks of the new parasite. During recent surveys worrying blight damage recurrences were observed in different Italian chestnut areas (in Piemonte, Trentino and Toscana regions) which were highly infested by the Chinese wasp. While biological control treatments against the parasite are carried out, it is necessary to set up integrated protocols for the management of chestnut orchards to allow the survival of trees and their productivity.

Keywords

• Castanea sativa
• Dryocosmus kuriphilus
• Cryphonectria parasitica
• Biological invasion
• Interactions
• Plant decline
• Manuring