High virulence of a plant-pathogenic virus (Cowpea mild mottle virus, Betaflexiviridae) leads to reduced performance of its insect vector (Bemisia tabaci, Hemiptera: Aleyrodidae)

• Ano de defesa: 2016
• Autor(a) principal: Trindade, Tiago Amaral
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Universidade Federal de Viçosa
• Palavras-chave em Português: Cowpea mild mottle virus; Bemisia tabaci; Vírus de plantas; Interações planta-patógeno; Virulência; Entomologia Agrícola
• Link de acesso: https://locus.ufv.br//handle/123456789/26691

Viral infection induces changes in host plants that can then affect performance of the vector of the virus. Here we assess the effects of the infection of soybean plants by two strains and a variant of CPMMV (Cowpea mild mottle virus) on survival and development of the whitefly (Bemisia tabaci MEAM1). We wished to know how the virulence of this pathogen would affect the insect vector. Thus, we used a mild isolate of strain CPMMV-BR1 and a virulent isolate of strain CPMMV-BR2. We hypothesized that the mild CPMMV-BR1 (referred to as the ‘mosaic strain’) has a positive effect on the performance of the whitefly, whereas the virulent CPMMV-BR2 (referred to as the ‘necrotic strain’) has a negative effect on the performance of the whitefly. Additionally, we tested the effects of a mild variant of the CPMMV-BR2 (the same isolate of the CPMMV- BR2, but after losing the capacity to cause necrosis symptoms) on survival and development of the vector. We also hypothesized that a loss of virulence has a positive effect on the performance of the whitefly. In agreement with our hypothesis, survival of whitefly nymphs was significantly reduced on plants infected with the necrotic strain, but survival and development on plants infected with the mosaic strain and plants infected with the mild variant were not affected. Therefore, high virulence of the CPMMV-BR2 strain in soybean plants has a negative effect not only on the performance of the vector but also on viral fitness since the virus depends on adult whiteflies for dispersal.