Abstract

DHAHRI, S. et al. Presence of Glycaspis brimblecombei and its Parasitoid Psyllaephagus bliteus in Tunisia and Portugal. Silva Lus. [online]. 2014, vol.22, n.1, pp.99-105. ISSN 0870-6352.

We report here for the first time the presence of Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) and its parasitoid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) in Tunisia, as well as the first record of the presence of P. bliteus in Portugal. Data regarding their geographical distribution, host plants and parasitism rates in Tunisia and Portugal, were collected. G. brimblecombei was observed for the first time in Tunisia in 2010 in the North coastal regions where it was found only on Eucalyptus camaldulensis Dehnh. Main host species in Portugal were E. camaldulensis, E. tereticornis Sm., E. rudis Endl. and E. ovata Labill.. Nine other species, including E. globulus Labill. were found to be resistant. In Tunisia, infestation levels were higher on the West regions (80.5%±4.0) compared to those on the East (8.8% ±4.4). Overall, parasitism rates were found to be low, on average 6.5%±0.8. In Portugal infestation levels varied from 5 to 75% but no geographical pattern emerged. Parasitism rates varied seasonally, from 1% in May to 35% in October, corresponding to the period of build-up and collapse of G. brimblecombei population. A density-dependence pattern is suggested by three weeks delay on the parasitized nymphs in relation to the total nymphs of G. brimblecombei. Further work will be needed to evaluate the efficacy of the parasitoid in controlling this psyllid.

Keywords : Eucalyptus; biological control; biological invasions; Red Gum Lerp; Psyllid.

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