title: Volatiles Emitted from Maize Ears Simultaneously Infected with TwoFusariumSpecies Mirror the Most Competitive Fungal Pathogen.
abstract: Along with barley and rice, maize provides staple food for more than half of the world population. Maize ears are regularly infected with fungal pathogens of theFusariumgenus, which, besides reducing yield, also taint grains with toxic metabolites. In an earlier work, we have shown that maize ears infection with singleFusariumstrains was detectable through volatile sensing. In nature, infection most commonly occurs with more than a single fungal strain; hence we tested how the interactions of two strains would modulate volatile emission from infected ears. For this purpose, ears of a hybrid and a dwarf maize variety were simultaneously infected with different strains ofFusarium graminearumandF. verticillioidesand, the resulting volatile profiles were compared to the ones of ears infected with single strains. Disease severity, fungal biomass, and the concentration of the oxylipin 9-hydroxy octadecadienoic acid, a signaling molecule involved in plant defense, were monitored and correlated to volatile profiles. Our results demonstrate that in simultaneous infections of hybrid and dwarf maize, the most competitive fungal strains had the largest influence on the volatile profile of infected ears. In both concurrent and single inoculations, volatile profiles reflected disease severity. Additionally, the data further indicate that dwarf maize and hybrid maize might emit common (i.e., sesquiterpenoids) and specific markers upon fungal infection. Overall this suggests that volatile profiles might be a good proxy for disease severity regardless of the fungal competition taking place in maize ears. With the appropriate sensitivity and reliability, volatile sensing thus appears as a promising tool for detecting fungal infection of maize ears under field conditions.
authors.affiliation: Molecular Phytopathology and Mycotoxin Research, University of GöttingenGöttingen, Germany; Integrative Fungal Research ClusterFrankfurt, Germany; Institute for Molecular Biosciences, University of FrankfurtFrankfurt am Main, Germany.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Sherif
authors.affiliation: Molecular Phytopathology and Mycotoxin Research, University of Göttingen Göttingen, Germany.
authors.forename: Eva-Maria
authors.initials: EM
authors.lastname: Becker
authors.affiliation: Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen Göttingen, Germany.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Herrfurth
authors.affiliation: Department of Plant Biochemistry, Albrecht-von-Haller-Institute for Plant Sciences, University of Göttingen Göttingen, Germany.
authors.forename: Ivo
authors.initials: I
authors.lastname: Feussner
authors.affiliation: Molecular Phytopathology and Mycotoxin Research, University of Göttingen Göttingen, Germany.
authors.forename: Petr
authors.initials: P
authors.lastname: Karlovsky
authors.affiliation: Integrative Fungal Research ClusterFrankfurt, Germany; Institute for Molecular Biosciences, University of FrankfurtFrankfurt am Main, Germany.
authors.forename: Richard
authors.initials: R
authors.lastname: Splivallo
keywords: Fusarium spp.; Zea mays; fungal pathogens; maize; oxylipins; sesquiterpenoids; volatile organic compounds