The dual nature of Lambertella corni-maris as an apple fruit pathogen and antagonist of Monilinia spp

Abstract

Lambertella corni-maris was isolated from a dark brown lesion on apple fruit cv. Golden Delicious collected from an orchard, and from stored apple fruit cv. Idared previously colonized with Monilia polystroma. The contrasting origin of the isolates led us to hypothesize that this fungus behaves differently in various contexts, which triggered the investigation of L. corni-maris as a pathogen and antagonist. Following identification based on cultural and molecular characteristics, isolates of different origin were characterized and their cultural, ecological, pathogenic, and antagonistic features were compared. This study has shown that L. corni-maris, originally isolated as an apple fruit pathogen and one as an antagonist of M. polystroma, have similar features in vitro and in vivo. The isolates vary widely in growth rate, cultural morphology, crystal production, intensity of dark zone and co-antagonism with two Monilinia species but can also function as apple fruit pathogens and inhibit and replace different Monilinia spp. on apple fruit. These findings reinforce their dual nature in different host-pathogen interactions. The data from this study are biologically intriguing and practically relevant, and have translative potential to exploit L. corni-maris as a model system for developing strategies to block brown rot of apple and to pinpoint virulence factors in the fungus for yellow rot management.