Phyllosticta solitaria is a plant pathogen that infects apple, pears, thornapples (cultivated and wild). P. solitaria causes apple blotch. Pathogen occurs in North America. It was reported only once in Europe in the mid-20th century in Denmark. Recently published reports from the USA suggest that losses caused by Phyllosticta solitaria has been decreasing in the last few years.

Pathogen prefers high temperature and humidity. Given the above, climatic conditions in PRA area are adverse for Phyllosticta solitaria. Fungus still could potentially pose a risk for apple orchards, because of lack of pathogens with the same ecological niche.

In case of climatic change Phyllosticta solitaria may cause serious losses in apple and pear crops.