Impact of Eucalyptus mosaics components on Glycaspis brimblecombei (Hemiptera: Aphalaridae) occurrence

The red gum lerp psyllid, Glycaspis brimblecombei, was introduced in Brazilian Eucalyptus plantations and now represents one of the main forest pests in the country. An integrated pest management strategy involves maximizing the use of environmental components, in order to restrain pests. Thus, this study aimed to investigate which components of a forest mosaic impact the occurrence of G. brimblecombei. The analyses included data for 502 mosaic plots with eucalypt plantation, in Sao Paulo State – Brazil, from 2019 to 2022 and recorded: diversity of plantation ages, diversity of genetic materials, proportion of area represented by each age, proportion of area represented by each clone, proportion of area with native vegetation and proportion of area with G. brimblecombei occurrence. As result, we found (i) there was no significant relationship between pest occurrence and the diversity of plantation ages or clones, (ii) there was a negative relationship between the pest presence and native vegetation, (iii) there was a positive relationship between pest occurrence and plantations with one and two years old, (iv) there was a positive relationship between pest presence and three genetic materials out of a total of thirteen materials. The results obtained in this study indicate the importance of maintaining portions of native vegetation and strategically allocating planting areas and critical clones as tools for the integrated management of G. brimblecombei in eucalyptus plantations.