Two distinct diseases can be caused by Colletotrichum spp.on apple (Malusdomestica): Apple bitter rot (ABR) and Glomerella leaf spot (GLS).ABR is an old fruit disease occurring in most countries where apple is commercially cultivated.In contrast, GLS was first observed in the USA in 1970, and since then, it has been reported as an emerging leaf disease in different countries, such as Brazil in 1988 and China in 2012.