X-Spot of Apple

Apples August 22, 2011 Print Friendly and PDF

The names X-spot, X-rot, and Nigrospora spot have been applied to a small, circular, depressed, necrotic spot typically on the calyx end of apple fruit in the mid-Atlantic region (Fig. 1). Although uncommon, incidence of X-spot as high as 86% was reported on unprotected 'Golden Delicious' and 'Rome Beauty' fruit in 1950. Other susceptible cultivars include 'Jonathan', 'Stayman Winesap', and 'York Imperial'.

Figure 1. X-spot is likely a fungal disease, although the pathogen is undetermined at this time. Photo: A. B. Groves, Virginia Tech.
X-spot on apple

 A fungus has been associated with X-spot lesions, but the typical lesion symptom has not been duplicated by controlled inoculation, and the disease cycle has not been resolved.

Fungicides applied for summer diseases provide effective control of X-spot.

 

 

 

Web resource: http://www.caf.wvu.edu/kearneysville/disease_descriptions/omxspot.html


Original text prepared by K.S. Yoder. The original version of this article appeared in The Mid-Atlantic Orchard Monitoring Guide (NRAES-75) and is reproduced with permission from the Natural Resource, Agriculture, and Engineering Service, Cooperative Extension, 152 Riley-Robb Hall, Ithaca, New York 14853-5701, U.S.A. (607) 255-7654. It has been edited for presentation here by Alan R. Biggs, West Virginia University.

Connect with us

  • Facebook

Welcome

This is where you can find research-based information from America's land-grant universities enabled by eXtension.org

LOCATE

Resources

Apple Rootstocks

  • All about understanding and choosing the right rootstock

Apple Cultivars

  • Characteristics, descriptions, and how to choose the best to grow and eat

Establishing an Apple Orchard

  • Buying and planting trees

Managing Apple Trees and Orchards

  • Insects, diseases, wildlife and other challenges

Propagating Apple Rootstocks and Trees

  • Grafting, budding, tissue culture, and all about how rootstocks are developed

Regional Resources

  • Links to apple information specific to your area

USDA / NIFA

This work is supported by the USDA National Institute of Food and Agriculture, New Technologies for Ag Extension project.