Kiwifruit Bacterial Canker: A Recent Disease for Modern Plant Pathologists

Abstract In the last century, the kiwi industry developed rapidly and starting from the 1950s, the kiwifruit plant began to be planted throughout the world, almost undisturbed and encouraged by the higher profitability in comparison with other traditional crops until the emergence of the bacterial canker disease caused by Pseudomonas syringae pv actinidiae (Psa) in the 1980s. The first strain was isolated in Japan, where it caused important damage, while later in Italy, a similar strain was not considered a serious threat. Psa has become a major threat since 2008, when a highly virulent strain was found in Italy. The occurrence of this strain in orchards was accompanied by severe symptoms, which turned into huge yield losses and even plant death. This strain spread rapidly all over the world, threatening local kiwifruit production, particularly in New Zealand, where it had numerous social consequences besides the economic impact. With an important scientific effort, the pathogen population and the principal virulence factors have been described, despite these are not fully understood. Due to the recent development of kiwifruit industry and pathogen emergence, the host-microbe interaction is an almost unique case to investigate pathogen evolution and adaptation to new hosts and environments. Information © The Author 2024