Copper sensitivity of Italian Pseudomonas syringae pv actinidiae strains

Pseudomonas syringae pv. actinidiae (Psa) is the agent of the bacterial canker of green and yellow-fleshed kiwifruit (respectively Actinidia deliciosa and A. chinensis). It is the cause of severe economic losses in Japan (Takikawa et al., 1989), South Korea (Koh et al., 1994) and Iran (Mazarei and Mostofipour, 1994). This pathogen was reported on A. deliciosa in Italy for the first time in 1994 (Scortichini, 1994) without yield losses up to 2008 when the disease infected most part of orchards located in Latium region. Psa is currently a worldwide pandemic disease, threatening the kiwifruit producing countries, particularly Italy, France, New Zealand and Chile. The current chemical control of Psa in the field is reliant on spraying of copper-based compounds (Koh et al., 1996; Nakajima et al., 2002; Vanneste et al., 2011). Unfortunately, copper may lead many bacteria to develop different strategies to overcome its toxicity (Nies, 1999). This study was undertaken to establish the copper sensitivity of many strains of Psa coming from North of Italy isolated during 2009-2013 years...............................