title: Host genotype is an important determinant of the cereal phyllosphere mycobiome.
abstract: The phyllosphere mycobiome in cereals is an important determinant of crop health. However, an understanding of the factors shaping this community is lacking. Fungal diversity in leaves from a range of cultivars of winter wheat (Triticum aestivum), winter and spring barley (Hordeum vulgare) and a smaller number of samples from oat (Avena sativa), rye (Secale cereale) and triticale (Triticum × Secale) was studied using next-generation sequencing. The effects of host genotype, fungicide treatment and location on fungal communities were explored. In total, 635 251 fungal internal transcribed spacer (ITS) reads were obtained from 210 leaf samples. Visual disease assessments and relative read abundance of Zymoseptoria tritici and Ramularia collo-cygni were strongly positively related. Crop genotype at the species level explained 43% of the variance in the total dataset, followed by fungicide treatment (13%) and location (4%). Indicator species, including plant pathogens, responding to factors such as crop species, location and treatment were identified. Host genotype at both the species and cultivar level is important in shaping phyllosphere fungal communities, whereas fungicide treatment and location have minor effects. We found many host-specific fungal pathogens, but also a large diversity of fungi that were relatively insensitive to host genetic background, indicating that host-specific pathogens live in a 'sea' of nonspecific fungi.
authors.affiliation: Department of Agroecology, Faculty of Science and Technology, Aarhus University, Forsøgsvej 1, DK4200, Slagelse, Denmark.
authors.forename: Rumakanta
authors.initials: R
authors.lastname: Sapkota
authors.affiliation: Department of Agroecology, Faculty of Science and Technology, Aarhus University, Forsøgsvej 1, DK4200, Slagelse, Denmark.
authors.forename: Kamilla
authors.initials: K
authors.lastname: Knorr
authors.affiliation: Department of Agroecology, Faculty of Science and Technology, Aarhus University, Forsøgsvej 1, DK4200, Slagelse, Denmark.
authors.forename: Lise Nistrup
authors.initials: LN
authors.lastname: Jørgensen
authors.affiliation: Slotsvaenget 11, 3400, Hillerød, Denmark.
authors.forename: Karen A
authors.initials: KA
authors.lastname: O'Hanlon
authors.affiliation: Department of Agroecology, Faculty of Science and Technology, Aarhus University, Forsøgsvej 1, DK4200, Slagelse, Denmark.
authors.forename: Mogens
authors.initials: M
authors.lastname: Nicolaisen
mesh_terms: D000935:Antifungal Agents / Q000494:pharmacology; D044822:Biodiversity; D002523:Edible Grain / Q000235:genetics* / Q000382:microbiology*; D005658:Fungi / Q000187:drug effects / Q000502:physiology*; D005838:Genotype; D064307:Microbiota / Q000187:drug effects; D025341:Principal Component Analysis; D013045:Species Specificity
chemical_list: D000935:Antifungal Agents
keywords: barley (Hordeum vulgare); cereals; fungal communities; fungicide; pathogen; pyrosequencing; wheat (Triticum aestivum)