Data from: Evolution of pathogenicity traits in the apple scab fungal pathogen in response to the domestication of its host

Understanding how pathogens emerge is essential to bring disease-causing agents under durable human control. Here, we used cross-pathogenicity tests to investigate changes in life history traits of the fungal pathogen Venturia inaequalis associated with host-tracking during the domestication of apple and subsequent host range expansion on the wild European crabapple (Malus sylvestris). Pathogenicity of 40 isolates collected in wild and domesticated ecosystems were assessed on the domesticated apple, its central Asian main progenitor (M. sieversii) and M. sylvestris. Isolates from wild habitats in the centre of origin of the crop were not pathogenic on the domesticated apple and less aggressive than other isolates on their host of origin. Isolates from the agro-ecosystem in central Asia infected a higher proportion of plants with higher aggressiveness, on both the domesticated host and its progenitor. Isolates from the European crabapple were still able to cause disease on other species but were less aggressive and less frequently virulent on these hosts than their endemic populations. Our results suggest that the domestication of apple was associated with the acquisition of virulences in the pathogen following host-tracking. The spread of the disease in the agro-ecosystem would also have been accompanied by an increase in overall pathogenicity.

阐明病原物的起源机制，是实现对致病原实施持久人类防控的核心前提。本研究通过交叉致病性试验，探究了苹果驯化过程中伴随宿主追踪的真菌病原物苹果黑星病菌（Venturia inaequalis）的生活史性状变化，以及该病原在欧洲野苹果（Malus sylvestris）上后续的宿主范围扩张情况。我们针对采集自野生与驯化生态系统的40株病原分离株，分别在栽培苹果、其中亚原生祖先种新疆野苹果（M. sieversii）以及欧洲野苹果上开展致病性测定。采自作物起源中心野生生境的分离株，无法侵染栽培苹果，且在其原生宿主上的致病力弱于其他分离株。采自中亚农业生态系统的分离株，在栽培宿主及其原生祖先种上均能侵染更高比例的植株，且致病力更强。采自欧洲野苹果的分离株仍可侵染其他物种，但相较于其本地种群，在这些宿主上的致病力更弱、致病频率更低。本研究结果表明，苹果驯化过程中伴随宿主追踪的同时，病原物也获得了相关毒力；而病害在农业生态系统中的传播，也伴随了整体致病性的提升。