Adaptation of a plant pathogen to partial host resistance: selection for greater aggressiveness in grapevine downy mildew
Idioma
en
Article de revue
Este ítem está publicado en
Evolutionary Applications. 2016, vol. 9, n° 5, p. 709-725
Blackwell
Resumen en inglés
An understanding of the evolution of pathogen quantitative traits in response to host selective pressures is essential for the development of durable management strategies for resistant crops. However, we still lack ...Leer más >
An understanding of the evolution of pathogen quantitative traits in response to host selective pressures is essential for the development of durable management strategies for resistant crops. However, we still lack experimental data on the effects of partial host resistance on multiple phenotypic traits (aggressiveness) and evolutionary strategies in pathogens. We performed a cross-inoculation experiment with four grapevine hosts and 103 isolates of grapevine downy mildew (Plasmopara viticola) sampled from susceptible and partially resistant grapevine varieties. We analysed the neutral and adaptive genetic differentiation of five quantitative traits relating to pathogen transmission. Isolates from resistant hosts were more aggressive than isolates from susceptible hosts, as they had a shorter latency period and higher levels of spore production. This pattern of adaptation contrasted with the lack of neutral genetic differentiation, providing evidence for directional selection. No specificity for a particular host variety was detected. Adapted isolates had traits that were advantageous on all resistant varieties. There was no fitness cost associated with this genetic adaptation, but several trade-offs between pathogen traits were observed. These results should improve the accuracy of prediction of fitness trajectories for this biotrophic pathogen, an essential element for the modelling of durable deployment strategies for resistant varieties.< Leer menos
Palabras clave
erosion
quantitative resistance
Palabras clave en inglés
evolvability
fitness cost
host specificity
obligate plant pathogen
virulence
Vitis vinifera
Orígen
Importado de HalCentros de investigación