What do we really know on the harmfulness of Cryptoblabes gnidiella (Millière) to grapevine? From ecology to pest management

Though the honeydew moth Cryptoblabes gnidiella (HM) was never deemed an important pest of grapevine in the Mediterranean area, recent observations led to consider this species as a primary carpophagous moth, as always believed in South America. Larval feeding accounts for a progressive grape decay due to superficial erosion of rachis and berry peduncles, with vascular system breakdown and proliferation of pathogenic rotting agents and saprophagous insects. Recent observations carried out over a three-year period (2015–2017) in Apulian vineyards (Southern Italy) confirmed that this moth pest shows four main flight periods per year, with relatively low captures from the beginning of May to the end of July and their gradual but substantial increase from beginning of August onwards. The presence on the bunches of an extremely small preimaginal population of HM in May, June and July, suggests the existence of alternative hosts for oviposition and offspring development in this timeframe. Overall, herein we summarized current knowledge available on biology, ecology and control of HM, adding new information on the relationships existing between the moth and the grapevine as well. In the final section, current and perspective control strategies to manage HM are outlined.