Mycosphaerella cucumis (Didymella bryoniae)

Gummy stem blight


Mycosphaerella cucumis (Didymella bryoniae) is a fungal plant pathogen that causes gummy stem blight.

Life cycle and appearance of Gummy stem blight

Mycosphaerella cucumis survives in crop debris and produces the sexual ascospores and asexual conida simultaneously. The spores germinate when free water is present on the plant, at high relative humidity (RH) and on wounds. Leaves can be infected directly, through wounds, hydathodes (the end of leaf veins) or the hair bases. Stems are infected through wounds and by the infected leaves through the petioles. Fruits are infected through the flowers. The newly produced ascospores are dispersed by air and the conidiospores by water drops, tools and hands of workers. The ascospores are the main source of dispersal of disease upwards in the crop and the conidia for spread of the disease downwards.

How to prevent Gummy stem blight