Physalospora malorum

Physalospora malorum is a species of fungus in the family Botryosphaeriaceae. It is a plant pathogen that primarily affects apple trees, but can also infect other fruit trees such as pear and peach trees.

Taxonomy

The species was first described in 1889 by mycologist Pier Andrea Saccardo. The genus name Physalospora comes from the Greek words physa, meaning bladder, and spora, meaning seed. This refers to the characteristic shape of the spores. The species name malorum is derived from the Latin word malus, meaning apple, indicating the primary host of this fungus.

Description

Physalospora malorum is characterized by its dark, spherical fruiting bodies known as pycnidia. These structures contain numerous spores, which are released when the pycnidia rupture. The spores are hyaline, unicellular, and have a smooth surface.

Pathogenicity

Physalospora malorum is a significant pathogen of apple trees, causing a disease known as apple blotch. The fungus infects the leaves, fruit, and twigs of the tree, causing dark, sunken lesions. In severe infections, it can lead to significant yield loss. The fungus can also infect other fruit trees, including pear and peach trees.

Management

Management of Physalospora malorum involves a combination of cultural practices and chemical control. Cultural practices include pruning infected branches and removing fallen fruit, which can harbor the fungus. Chemical control typically involves the application of fungicides.

See also

• List of apple diseases
• List of pear diseases
• List of peach and nectarine diseases