Open AccessNiche differentiation within a cryptic pathogen complex: climatic drivers and hyperparasitism at multiple spatial scales
Author(s) -
Faticov Maria,
DesprezLoustau MarieLaure,
Kiss Levente,
Massot Marie,
d'Arcier Julie Faivre,
Mutz Jessie,
Németh Márk Z.,
Roslin Tomas,
Tack Ayco J. M.
Publication year - 2022
Publication title -
ecography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.973
H-Index - 128
eISSN - 1600-0587
pISSN - 0906-7590
DOI - 10.1111/ecog.06062
Subject(s) - powdery mildew , biology , ecological niche , ecology , niche , phenology , interspecific competition , species complex , habitat , botany , biochemistry , gene , phylogenetic tree
Pathogens are embedded in multi‐trophic food webs, which often include co‐occurring cryptic species within the same pathogen complex. Nonetheless, we still lack an understanding of what dimensions of the ecological niche might allow these cryptic species to coexist. We explored the role of climate, host characteristics (tree autumn phenology) and attack by the fungal hyperparasite Ampelomyces (a group of fungi attacking plant pathogens) in defining the niches of three powdery mildew species ( Erysiphe alphitoides , E. hypophylla and E. quercicola ) within a cryptic pathogen complex on the pedunculate oak Quercus robur at the continental (Europe), national (Sweden and France) and landscape scales (a 5 km 2 island in southwestern Finland). Previous studies have shown that climate separated the niches of three powdery mildew species ( E. alphitoides , E. hypophylla and E. quercicola ) in Europe and two species ( E. alphitoides and E. quercicola ) in France. In our study, we did not detect a significant relationship between temperature or precipitation and the distribution of E. alphitoides and E. hypophylla present in Sweden, while at the landscape scale, temperature, but not relative humidity, negatively affected disease incidence of E. alphitoides in an exceptionally warm year. Tree variation in autumn phenology did not influence disease incidence of powdery mildew species, and hyperparasite presence did not differ among powdery mildew species at the continental, national and landscape scale. Climate did not affect the distribution of the hyperparasite at the continental scale and at the national scale in Sweden. However, climate affected the hyperparasite distribution in France, with a negative relationship between non‐growing season temperature and presence of the hyperparasite. Overall, our findings, in combination with earlier evidence, suggest that climatic factors are more important than species interactions in defining the niches of cryptic species within a pathogen complex on oak.