Ressurgencia de uma antiga ameaça: Gorgulho-do-eucalipto Gonipterus platensis (Coleoptera: Curculionidae) (original) (raw)

The Eucalyptus plantations represent 72% of total area of forest plantations in Brazil with 5.56 million hectares. About his total, one million ha and 225,000 ha are in States of São Paulo and Paraná, respectively. The forest products represented 5.5 % of Brazilian GDP in 2014. Eucalyptus plantations, in special in these two States, are suffering with return of a old pest. The Eucalyptus Snout Beetle Gonipterus platensis (Coleoptera: Curculionidae), a Australian insect and present in countries of four Continents (Oceania, Africa, Americas and Europe). This pest has caused tip defoliation in trees of different ages. This damage leads trees multishooting and reduce the wood volume up to 29 %. The main management strategy to Eucalyptus snout beetle in biological control with egg parasitoid Anaphes nitens (Hymenoptera: Mymaridae). This parasitoid, of Australian origin, too, was introduced in South America by Argentina in 1928 and spread naturally to Uruguay and Brazil, where it was detected in 1950´s. The pest spread in Brazil in States of Rio Grande do Sul, Santa Catarina, Paraná, São Paulo and Espirito Santo and its specific parasitoid spread together, except in Espirito Santo, where was carried a Classical Biological program, with parasitoid introduction from Rio Grande do Sul. In all cases, the parasitoid presented high egg parasitism rates. But, G. platensis reappeared in South region of Sâo Paulo in December, 2012 and it has spreading to Central region of this State and to Northeastern of Paraná. In these States, the parasitism mean rate has varied between 30 to 60 % only, comparing with rates of 90 % in other places. A hypothesis of this reduced parasitism rate can be related with climatic changes in this region. Studies are ongoing to verify this hypothesis. Other control options are the introduction of new Anaphes species in Brazil, as Anaphes tasmaniae and A. inexpectatus (Hymenoptera: Mymaridae), evaluation of entomopathogenic fungi and nematodes, prospection of natural predators and tests with chemical insecticides.