Parâmetros vibratórios para detecção de atividade alimentar do inseto Ceropsylla (Hemiptera: Psyllidae) em galhas foliares de Pouteria ramiflora (Sapotaceae)

Abstract

Galls are plant structures made through the manipulation of the plant by a galling insect, which provides protection and nutrition until its development and maturation. Because it is a closed structure, it is not possible to directly analyze the feeding behavior of the insects. Therefore, this study proposes a new methodology to analyze the feeding behavior of galling insects in order to not compromise the gall’s structure and disrupt the insect’s development. For this purpose, experiments were carried out with the insect Ceropsylla sp.(Hemiptera: Psyllidae), which induces galls in Pouteria ramiflora (Sapotaceae), through a non-invasive methodology using the laser vibrometer PDV-100 (Politec®), in order to analyze vibration patterns, and select the suitable parameters to describe its feeding. The analyses were made simulating both phloem continuous and interrupted flows, wherein these sucking insects feed on. The results showed that the vibration pattern analyses of Ceropsylla sp. are efficient in both high and low vibrometer sensitivity. The parameters of amplitude and frequency were discrepant in situations with or without flow in the phloem, being larger in continuous flow. Thus, these vibrations may indicate that the insect is feeding inside the larval chamber. The present study, therefore, inaugurates an important methodology for study of interactions between galling insects and host plants and makes it possible to investigate the feeding behavior of these insects without hindering its development.