ABSTRACT
Many comprehensive reviews and compendia dealing with citrus diseases have been published (Fawcett 1936; Klotz 1973, 1978; Wallace 1978; Timmer et al. 1999, 2000). However, specic references to diseases of bergamot (Citrus bergamia) are rarely found as cultivation of this citrus species is economically relevant only in very restricted areas. As far as the phytosanitary status of bergamot industry in Calabria (southern Italy), the major bergamot producing area in the world, is concerned, three reports are available in the scientic literature of the last 40 years. The rst two (Terranova and Cutuli 1975; Terranova et al. 1984) cite several virus and virus-like diseases, including exocortis, cachexia-xyloporosis, concave gum, cristacortis, and impietratura, that were diagnosed on the basis of visual symptoms on naturally infected trees and on articially inoculated indicator test plants, while the third one (Grasso and Polizzi 1988) is a scant list of fungal and bacterial diseases extrapolated from previously published papers concerning citrus diseases in general. Advances in our knowledge of citrus diseases have since occurred, and some diseases such as Alternaria brown spot had not yet
4.1 Introduction .................................................................................................... 37 4.2 Phytophthora Gummosis, Foot Rot, Root Rot, and Fruit Brown Rot ............. 38 4.3 Bergamot Gummosis ......................................................................................40 4.4 Mal Secco Disease .......................................................................................... 41 4.5 Fruit Diseases ................................................................................................. 41
4.5.1 Stylar-End Rot .................................................................................... 41 4.5.2 Septoria Spot ....................................................................................... 42 4.5.3 Alternaria Brown Spot ........................................................................ 42 4.5.4 Anthracnose ........................................................................................ 43 4.5.5 Sooty Mold ......................................................................................... 43
4.6 Citrus Tristeza Virus ....................................................................................... 43 4.7 Other Virus and Virus-Like Diseases ............................................................44 4.8 Diseases Caused by Prokaryotes ....................................................................44 References ................................................................................................................ 45
emerged at that time (Faedda et al. 2011), while others such as citrus tristeza virus have assumed much greater importance (Davino et al. 2011). Despite the lack of detailed information, it can be inferred that bergamot is susceptible to numerous diseases affecting other commercially important citrus species. Like other plant diseases, citrus diseases can be classied as infectious (biotic) or noninfectious (abiotic). Biotic diseases are caused by various agents including viroids, virus, phytoplasmas, bacteria, fungi and oomycetes (pseudofungi). Conversely, abiotic diseases are caused by adverse environmental conditions, injuries caused by improper application of chemicals, nutritional disorders, and genetic alterations. A third group includes diseases whose etiology has not been yet determined. In this chapter only major diseases of bergamot occurring in Calabria or threatening the bergamot industry in this region of southern Italy are reported, and management strategy is briey discussed.
