The effect of climatic conditions on the seasonality of pest insect populations in eucalyptus plantations in the neotropics

Abstract

Eucalyptus (Eucalyptus spp., Mirtaceae) stands out for its remarkable regeneration capacity, making it a valuable tool for recovering degraded areas and for reforestation. Despite its Australian origins, eucalyptus has shown remarkable adaptation to the Brazilian tropical climate, contributing to the wood productivity of the country. However, the extensive monoculture of eucalyptus can increase pest incidence, thus being a significant challenge for the forestry sector, which suffers production losses of up to 30%. We analyzed the occurrence of 11 pest insect species in 450 eucalyptus stands over 9 years in the southeastern region of Brazil in our study. We related pest occurrences to specific year periods and climatic variations using circular uniformity analysis and zero-inflated models. We found that the species generally had isolated peaks of occurrence during the year and that the increase in the occurrence of at least five species was related to temperature or precipitation. The results highlight the sensitivity of pests to climatic conditions, showing the importance of management strategies to ensure the sustainability and productivity of eucalyptus plantations. We can develop more effective management strategies by understanding how these variables interact with insect populations, contributing to the sustainability and productivity of eucalyptus plantations with less aggressive environmental practices.