Diagrammatical scale to quantify herbivory severity on feijoa leaf caused by Paraulaca dives (Coleoptera: Chrysomelidae)

Abstract

The aims of this work were to characterize the damage caused by Paraulaca dives in feijoa (Acca sellowiana) and develop a diagrammatic scale to evaluate the severity of herbivory. The evaluations were carried out in a feijoa progenies orchard with eight-year-old. The beetles caused damage mainly on leaves, from October to December (spring season). The distribution of beetles in the orchard occurred randomly, not following a defined pattern of incidence. The diagrammatic scale of herbivory severity was represented by seven levels (1%, 3%, 5%, 7%, 15%, 32%, and 55% of the leaf area consumed). The use of this diagrammatic scale significantly increased the precision and accuracy of severity estimates by inexperienced evaluators. This can help in strategies to control this pest to expand the cultivation of feijoa in Brazil.