Identification of Paramyrothecium foliicola causing crater rot in eggplant and its potential hosts under controlled conditions

Fruit diseases are among the major problems that negatively affect eggplants (Solanum melongena L.). With climate change, new pathogens may potentially emerge and threaten the yield and profitability of eggplant production. This study elucidates the causal agent of a crater rot in eggplant fruit. The disease appears as shallow to deep and crater-shaped lesions on infected fruits. Olive-coloured sporodochia and dark exudates appeared around the centre of the lesion. The fungal pathogen associated with the crater rot was identified as Paramyrothecium foliicola L. Lombard & Crous. The fungus was pathogenic to eggplant in two independent, detached fruit assays. The fungus also induced crater rot on wounded tomato and pepper fruits. The same fungus was consistently re-isolated from the inoculated fruits satisfying Koch's postulates. In an attempt to determine the potential host range of this fungal pathogen, 45 plant species from 21 plant families were assessed for pathogenicity under detached fruit or leaf assays. A wide range of plant species was susceptible to P. foliicola MBEPFR05 in either wounded or unwounded inoculations. This is the first report of P. foliicola causing crater rot in eggplant. This study also demonstrates the ability of the fungus to infect other economically important plants. Crater rot may become a problem in vegetable production and thus entails that more research would be needed considering little information on crater rot epidemiology and its management.