Genetic Diversity of <i>Epicoccum nigrum</i> and its Effects on <i>Fusarium graminearum</i>

Abstract

<i>Epicoccum nigrum</i> is a saprophytic or endophytic fungus that is found worldwide. Because of the antagonist effects of <i>E. nigrum</i> on many plant pathogens, current studies on <i>E. nigrum</i> have focused on the development of biological control agents and the utilization of its various metabolites. In this study, <i>E. nigrum</i> was collected from a wheat field, and its genetic diversity was analyzed. Phylogenetic analyses identified 63 isolates of <i>E. nigrum</i> divided into seven groups, indicating a wide genetic diversity. Isolates antagonized the wheat pathogen <i>Fusarium graminearum</i>, and reduced disease symptoms caused by <i>F. graminearum</i> in wheat coleoptiles. Moreover, pretreatment of wheat coleoptiles with <i>E. nigrum</i> induced the upregulation of pathogen-related (PR) genes, PR1, PR2, PR3, PR5, PR9, and PR10 in wheat coleoptiles responding to <i>F. graminearum</i> invasion. Overall, this study indicates that <i>E. nigrum</i> isolates can be used as biological pathogen inhibitors applied in wheat fields.