Potential impact of Entomophaga maimaiga Humber, Shimazu, and Soper (Entomophthorales Entomophthoraceae) on the lepidopteran fauna inhabiting cork forests in Sardinia (Italy).


Periodic outbreaks of forest defoliators like the gypsy moth cause severe impact to the forest ecosystem, which is normally counterbalanced by the action of their natural enemies, including predators, parasitoids, and entomopathogens. Among the latter, the host-specific fungus Entomophaga maimaiga can be very effective under favourable conditions. Whilst its close evolutionary relationship with gypsy moth, this entomopathogen has never been detected in certain forest areas where L. dispar is a common pest. The results of three years laboratory assays with two different strains of E. maimaiga from Bulgaria and Croatia against Lepidopteran species inhabiting cork oak forests in Sardinia are reported. Significant toxicity and virulence against gypsy moth larvae exposed to soil contaminated with resting spores of the fungus was detected for both strains, even if the strain from Bulgaria was significantly more effective. Significant lethal effects were observed also on M. neustria larvae, but a successful development and reproduction of the fungus within insect cadavers was detected only in the gypsy moth. No significant effects were observed on other Lepidopteran species.  Given a proper choice of candidate strains, the introduction of E. maimaiga in Sardinia, to manage the disruptive action of the gypsy moth would be desirable.


Lymantria dispar; Malacosoma neustria; entomopathogenic fungi; host specifity; bioinsecticide

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