Emerging vegetable crop diseases and their management options

Vegetable crops are economically important throughout the world and they all share some common features, such as high value, globalisation of the seed market, continuous intensification and innovation of their production systems, the presence of a high number of crops and varieties, and a limited availability of chemical pesticides for their disease management. In this review, we focus on fungal plant pathogens, although several diseases caused by bacteria are becoming important. Many diseases caused by soilborne pathogens, such as Fusarium oxysporum (different formae speciales), Sclerotinia sclerotiorum, Rhizoctonia solani, Pythium spp. and Phytophthora spp., become more severe over the last few years. Many of these diseases can be considered the consequence of the profound changes that soil disinfestation has undergone since the use of methyl bromide was prohibited in 2005. In the meantime, new hosts have been detected for diseases caused by foliar pathogens (Alternaria spp., Stemphylium spp. Fusarium equiseti, Albifimbria verrucaria, Paramyrothecium roridum), often as a consequence of climate change. The phytopathological situations of vegetable crops is discussed hereafter, with special emphasis on Italy, which is one of the most important vegetable production countries in Europe (not worldwide). The evolution of some diseases as a possible consequence of the current limitations in the use of chemicals, of the globalisation of the markets and/or of climate change is critically discussed. The disease management options that are currently available (e.g. the use of healthy planting material, host resistance, soil health, soilless systems, biological control, and integrated pest management) are discussed.