Apple scab

Not to be confused with Applecrab.
Apple scab
The main symptom of apple scab in infected trees is the development of brown lesions on the foliage and fruits.
Causal agentsVenturia inaequalis
HostsApple
EPPO CodeVENTIN

Apple scab is a common disease of plants in the rose family (Rosaceae) that is caused by the ascomycete fungus Venturia inaequalis.[1] While this disease affects several plant genera, including Sorbus, Cotoneaster, and Pyrus, it is most commonly associated with the infection of Malus trees, including species of flowering crabapple, as well as cultivated apple.[2][3] The first symptoms of this disease are found in the foliage, blossoms, and developing fruits of affected trees, which develop dark, irregularly-shaped lesions upon infection.[4][5] Although apple scab rarely kills its host, infection typically leads to fruit deformation and premature leaf and fruit drop, which enhance the susceptibility of the host plant to abiotic stress and secondary infection.[6][5] The reduction of fruit quality and yield may result in crop losses of up to 70%, posing a significant threat to the profitability of apple producers.[6] To reduce scab-related yield losses, growers often combine preventive practices, including sanitation and resistance breeding, with reactive measures, such as targeted fungicide or biocontrol treatments, to prevent the incidence and spread of apple scab in their crops.[7]

Apple scab on crabapple, lesions are visible on the leaves.
  1. ^ "Apple Disease - Apple Scab". Penn State Extension. Retrieved 2020-02-18.
  2. ^ "Apple scab of apples and crabapples". extension.umn.edu. Retrieved 2020-03-09.
  3. ^ "Apple Scab". Center for Agriculture, Food and the Environment. 2015-03-06. Retrieved 2020-03-09.
  4. ^ Agriculture, Ministry of. "Apple Scab Management in British Columbia - Province of British Columbia". www2.gov.bc.ca. Retrieved 2020-02-02.
  5. ^ a b Gauthier, Nicole (2018). "Apple scab". American Phytopathological Society. Retrieved 2020-02-02.
  6. ^ a b Jha, G., Thakur, K., & Thakur, P. (2009). The Venturia Apple Pathosystem: Pathogenicity Mechanisms and Plant Defense Responses. Journal of Biomedicine and Biotechnology, 2009. doi:10.1155/2009/680160
  7. ^ Bowen, Joanna K.; Mesarich, Carl H.; Bus, Vincent G. M.; Beresford, Robert M.; Plummer, Kim M.; Templeton, Matthew D. (2011). "Venturia inaequalis: the causal agent of apple scab". Molecular Plant Pathology. 12 (2): 105–122. doi:10.1111/j.1364-3703.2010.00656.x. ISSN 1364-3703. PMC 6640350. PMID 21199562.