Filamentous fungus (Ascochyta pisi), SEM

Coloured scanning electron micrograph (SEM) of the branched, filamentous fungus (Ascochyta pisi). Ascochyta pisi is a plant pathogen that causes ascochyta blight on the pea plant (lesions occur on stems, leaves and pods). It is a phytopathogenic fungus responsible for pea anthracnose. Ascochyta produces toxic metabolites, the main phytotoxin called ascosalitoxin. The same disease symptoms can also be caused by Ascochyta pinodes - the two fungi are not easily distinguishable. The genus Ascochyta belongs to the Ascomycota, a major division of Fungi. Ascomycota species are commonly known as the Sac Fungi. When reproducing sexually, they produce spores (ascospores) in a distinctive cell called an ascus. Some of the members of the Ascomycota do not reproduce sexually and do not form asci or ascospores. Magnification: x300 when shortest axis printed at 25 millimetres.