Genetic and Biochemical Characterization of Nectria haematococca Strains with Adhesive and Adhesion-Reduced Macroconidia

Abstract

A previous study reported the isolation of two mutants (LE1 and LE2) of the plant pathogenic fungus Nectria haematococca (anamorph, Fusarium solani f. sp. cucurbitae ) with macroconidia with reduced ability to adhere (Att - ) to zucchini fruits and polystyrene. The adhesion-reduced-phenotype in LE1 and LE2 macroconidia is temperature sensitive and dependent on the concentration of nutrients. Classical genetic analysis of progeny derived from LE1 identified a mutation in a genetic locus, named Att1 . The 90-kDa glycoprotein and macroconidial tip mucilage which were previously associated with the development of adhesion competence in Att + macroconidia are specifically associated with macroconidia; neither is produced on microconidia, which are relatively nonadherent. However, macroconidia of both Att + and Att - strains produce the 90-kDa glycoprotein and the macroconidial tip mucilage.