How Did Host Domestication Modify Life History Traits of Its Pathogens?

Abstract

Understanding evolutionary dynamics of pathogens during domestication of their hosts and rise of agro-ecosystems is essential for durable disease management. Here, we investigated changes in life-history traits of the fungal pathogen Venturia inaequalis during domestication of the apple. Life traits linked to fungal dispersal were compared between 60 strains that were sampled in domestic and wild habitats in Kazakhstan, the center of origin of both host and pathogen. Our two main findings are that transition from wild to agro-ecosystems was associated with an increase of both spore size and sporulation capacity; and that distribution of quantitative traits of the domestic population mostly overlapped with those of the wild population. Our results suggest that apple domestication had a considerable impact on fungal characters linked to its dispersal through selection from standing phenotypic diversity. We showed that pestification of V. inaequalis in orchards led to an enhanced allocation in colonization ability from standing variation in the wild area. This study emphasizes the potential threat that pathogenic fungal populations living in wild environments represent for durability of resistance in agro-ecosystems.

A Trade-Off Between Sporangia Size and Number Exists in the Potato Late Blight Pathogen Phytophthora infestans, and Is Not Altered by Biotic and Abiotic Factors

“…Interestingly, we also showed a clear effect of potato cultivars on SS, with smaller sporangia on Robijn – especially compared to Bintje. A similar observation was reported in P. viticola (Delmotte et al, 2014) and Venturia inaequalis (De Gracia et al, 2015), suggesting a possible selection by host on this trait among sporulating plant pathogens. Regarding temperature, the thermal optimum for P. infestans development is around 18–20°C (Mizubuti and Fry, 1998; Mariette et al, 2016), and spore production quickly decreases beyond this.…”

“…Conversely, small spores might have higher aerial dispersal abilities and could therefore tend to deposit further to the source than larger ones (Norros et al, 2014). Nevertheless, owing to the lack of empirical evidences, the link between asexual spore size and such fitness aspects remain uncertain (De Gracia et al, 2015). Further research efforts on this topic are thus needed and it would be particularly crucial to study the impact of offspring size on virulence or disease lesion development in fungal plant pathogens.…”

Plant Pathogen Life-History Traits and Adaptation to Environmental Constraints

“…Interestingly, we also showed a clear effect of potato cultivars on SS, with smaller sporangia on Robijnespecially compared to Bintje. A similar observation was reported in P. viticola (Delmotte et al, 2014) and Venturia inaequalis (De Gracia et al, 2015), suggesting a possible selection by host on this trait among sporulating plant pathogens. Regarding temperature, the thermal optimum for P. infestans development is around 18-20 • C (Mizubuti and Fry, 1998;, and spore production quickly decreases beyond this.…”

Quantitative interactions driveBotrytis cinereadisease outcome across the plant kingdom

“…(Whitehead et al, 2017). Domestication was also shown to affect interaction with specialist pathogens (Karasov et al, 2014, Whitehead et al, 2017, Stukenbrock and McDonald, 2008, De Gracia et al, 2015. When infected with Botrytis, only tomato and lettuce showed the expected decreased resistance in high improvement genotypes (Fig.…”