Temporal variations of lepidoptera collected in an Eucalyptus plantation in the State of Goias, Brazil

Lepidopterans are considered an important group of Eucalyptus pests in Braz il due to severe losses in wood production arising from defoliation. Biweek ly collections were made in the State of Goias, Brazil as part of a study o f the population dynamics and the effects of temperature and rainfall on Le pidoptera pests of Eucalyptus. Lepidoptera were collected with five light t raps installed at two meters high with black light and powered by a 12 volt battery. These insects were divided into groups according to their importa nce as pests of Eucalyptus: group 1: 11 primary pests; group 2: 10 secondar y pests; group 3: 64 species without defined importance to Eucalyptus; and group 4: non-identified species. Among the primary pests, Thyrinteina arnob ia (Geometridae), Eupseudosoma aberrans (Arctiidae) and Sarsina violascens (Lymantriidae) were the most frequent, the last two being constant (> 50% o f collections) and the first one accessory (25-50%). Idalus admirabilis (Ar ctiidae) and Eacles imperialis magnifica (Saturniidae) were the most freque nt secondary pests, the first being constant and the second accessory. Most of the Lepidoptera species were collected during the coldest and driest mo nths, which indicates that these conditions could favour the occurrence of Lepidoptera outbreaks in plantations of Eucalyptus in this region of Brazil . For this reason, population monitoring of these species should be intensi fied during these periods.