Host-plant preference of Philaenus spumarius, the main European vector of Xylella fastidiosa, and their effect on the insect development

• Autor(a) principal: Ksouri, Nour
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10198/28633
• topic: The meadow spittlebug; Vector; Cover-ground vegetation; OQDS; Olfactometer; Gram-negative; Domínio/Área Científica::Ciências Agrárias::Biotecnologia Agrária e Alimentar

Philaenus spumarius (Linnaeus, 1758) (Hemiptera: Aphrophoridae), commonly known as the meadow spittlebug, has recovered scientists’ attention for decades and has been extensively studied for its biological and ecological interests. However, this species has been rarely associated with significant economic or agricultural damage until the detection of Xylella fastidiosa (Wells et al. 1987) (Xathomonadales: Xanthomonadaceae), a plant pathogenic bacterium, in Europe for the first time in Italy in 2013. Philaenus spumarius has been identified to have a key role in the pathogen's propagation, being its essential transmission vector in Europe. Since currently, there is no cure for X. fastidiosa, vector control is perceived as the main tool to limit the spread of this pathogen. Therefore, understanding the choice of host plants and how they affect vector insect development can be fundamental for implementing approaches to manipulate the behavior of the vector and implement sustainable control strategies. In this sense, this work aims to evaluate the selection of host plants by nymphs and adults of P. spumarius, and their effect on the development of the insect vector. For that, we studied, in field conditions, the effect of four host plants, namely C. myconis S. tenerrimus, C. arvensis, and C. segetum, in the development of P. spumarius. We assessed the olfactory response of nymphs, at different soil humidity (10%, 50%, and 70%), and adults of P. spumarius towards the four plants (and the olive tree, only for the adults). Additionally, the volatile profile of the plants was also assessed, and we developed models to predict the effect of the volatiles produced by these plants on insect behavior. The plant species generally does not significantly affect the insect's morphological parameters. The choice made by P. spumarius nymphs was significantly affected by the plant species and the soil's percentage of water content. Sonchus tenerrimus and C. myconis were the two most chosen plants by the nymphs. The olfactory response of the adults of P. spumarius revealed that the sex of the insects did not influence the choice of plants and that S. tenerrimus was the most preferred plant by females when compared to C. segetum, C. arvensis, and the control. The models suggested that the nymphs and adults of P. spumarius are repelled by D-Limonene. Understanding how these insects interact with their environment is crucial to create effective control strategies.