Emergence of new diseases in pip fruit in Belgium
Abstract: The past decades global warming and climate changes resulted in higher temperaturesin spring and summer, more extreme weather conditions and rise in carbon dioxide and ozonelevels. The temperature rise in the central and northern part of Europe has brought about a shift ofsome diseases from the southern part of Europe upwards to the more northern regions. Moreover,these climate changes can bring about changes in plants that will affect their interactions withpathogens. Changes in plant architecture, for example, may influence the microclimate and assuch the risk of infection. Furthermore, abiotic stress such as heat or drought may also contributeto plant susceptibility. The past years some upcoming diseases, which may be linked to globalwarming or climate changes are noticed in Belgium. For pear, some emerging diseases inBelgium are Stemphylium vesicarium in the orchard and Phacidiopycnis (stem end rot),Neofabraea or bull’s eye rot, Phialophora side rot and Coprinus snow mold during storage.Symptoms of these last three decay fungi are quite similar in an early stage and needs furtherdetection methods for exact determination. During spring 2011, powdery mildew was for the firsttime observed on Conference and Durondeau pears in Belgium, which resulted in strongrusseting symptoms. On apple, black rot (Sphaeropsis malorum) is an upcoming problem whichstarted in organic Elstar orchards. Besides that secondary diseases can become more dominant asa consequence of the changed availability in fungicides.