Phytoparasitica (2017) 45, 85-93

Jesús Selfa, Carlo Polidori, Josep Daniel Asís, Luis De Pedro, Juli Pujade-Villar and José Tormos (2017)
Random pattern of parasitism and female-biased sex ratio in the egg parasitoid Neochrysocharis formosa attacking the pine sawfly Diprion pini in mountain forests of Spain
Phytoparasitica 45 (1), 85-93
Abstract: The most harmful hymenopteran pests of Pinus sylvestris L. are conifer sawflies from the family Diprionidae, including the widespread Diprion pini (L.). Natural enemies of this pest are still poorly known in many European areas where attacks occur. We studied the egg parasitoids of D. pini at four sites in two mountainous areas of Spain: the Sierra de Francia (western Spain) and the Sierra de Albarracín (eastern Spain). At all sites, the dominant egg parasitoid was Neochrysocharis formosa (Westwood) (Hymenoptera: Eulophidae), whereas other three chalcidoid species were rare. All these species were previously recorded in association with D. pini, but we report here their first record in Spain. Neochrysocharis formosa attacked up to 32.3% of egg clusters of D. pini in the Sierra de Albarracín and 18.5% in the Sierra de Francia. In the attacked egg clusters, this species parasitized up to 35% of eggs in the Sierra de Albarracín and 23.7% in the Sierra de Francia, with a marked female-biased sex ratio. Contrary to the clustered pattern of parasitism observed for N. formosa while attacking other gregarious diprionids, the oviposition in egg clusters of D. pini followed a random pattern, probably due to the froth roof (spumous coating) that covers its eggs and interferes with the egg-searching behavior of females. Indeed, other parasitoid species of D. pini have been reported to behave similarly.
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Link to article at publishers website
Database assignments for author(s): Jesús Selfa, José Tormos

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Diprion pini	Pine (Pinus)	Spain (continental)
Closterocerus formosus (parasitoid)	Diprion pini	Pine (Pinus)	Spain (continental)