Major and Emerging Fungal Diseases of Citrus in the Mediterranean Region

This chapter deals with major endemic and emerging fungal diseases of citrus as well as with exotic fungal pathogens potentially harmful for citrus industry in the Mediterranean region, with particular emphasis on diseases reported in Italy and Maghreb countries. The aim is to provide an update of both the taxonomy of the causal agents and their ecology based on a molecular approach, as a preliminary step towards developing or upgrading integrated and sustainable disease management strategies. Potential or actual problems related to the intensification of new plantings, introduction of new citrus cultivars and substitution of sour orange with other rootstocks, globalization of commerce and climate changes are discussed. Fungal pathogens causing vascular, foliar, fruit, trunk and root diseases in commercial citrus orchards are reported, including Plenodomus tracheiphilus, Colletotrichum spp., Alternaria spp., Mycosphaerellaceae, Botryosphaeriaceae, Guignardia citricarpa and lignicolous basidiomycetes. Diseases caused by Phytophthora spp. (oomycetes) are also included as these pathogens have many biological, ecological and epidemiological features in common with the true fungi (eumycetes).