Diseases

Pear Septoria Leaf Spot

Pyrus communis L.

A fungal disease of pear caused by Septoria piricola Desm. (teleomorph Mycosphaerella sentina), manifested as white spots with a dark border and black pycnidia on leaves and fruits.

In the reference 9 varieties crop European pear, where this is mentioned in the description.

The pathogen develops in two stages: the conidial stage Septoria piricola and the ascomycete stage Mycosphaerella sentina. The first symptoms of infection appear shortly after flowering, reaching their peak in midsummer. Round light-gray or whitish spots with a dark-brown border form on the leaves, with black dots—pycnidia—developing in their centers over time. Severe infection leads to premature leaf drop, which reduces the tree's winter hardiness, and dark sunken areas may occur on the fruits.

Three main variations of spotting are distinguished, with sizes ranging from 0.5 to 7 mm, depending on the cultivar and the virulence of local pathogen populations. Genetic resistance of the crop is often polygenic in nature, without clearly identified major genes. Representatives of East Asian species, such as Pyrus ussuriensis, which are used in breeding as sources of donor traits for developing new varieties, often possess high resistance.

General information about the subject — on the page Septoria leaf blotch.

Sources8

Varieties of European pear mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.