Insect-mediated vectoring of Pseudomonas syringae pv. actinidiae

From 2008, kiwifruit production and the total cultivated area decreased considerably, due to the pandemic spread of the bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa). This bacterium is able to infect host plants via natural openings or wounds, such as those caused by sucking insects. These insects are also known to be able to transmit other bacterial pathogens in different species. The present work aimed to investigate the role of Metcalfa pruinosa Say, 1830, one of the most common sucking insects to affect kiwifruit vines, in plant-to-plant transmission of Psa. The percentage of contaminated insects collected from infected orchards was evaluated to confirm the ecological relevance of M. pruinosa in the spread of bacterial canker of kiwifruit. This study demonstrated the survival of Psa in the M. pruinosa digestive trait, and the insect’s ability to vector the pathogen to healthy plants.