Pseudomonas syringae pv. actinidiae: chemical control, resistance mechanisms and possible alternatives

Abstract

Pseudomonas syringae pv. actinidiae (Psa) is a Gram-negative bacterium that causes the bacterial canker of both green (Actinidia deliciosa) and yellow (Actinidia chinensis) fleshed kiwifruit. Since the emergence of an economically devastating Psa outbreak in Japan in the 1980s, the disease took a contagious turn causing severe economic loss to kiwifruit industries in Italy, South Korea, Spain, New Zealand and other countries. Research shows that the pathogenic strains isolated from different infected orchards vary in their virulence characteristics and have distinct genes coding for the production of different toxins. The global Psa outbreak has activated research around the world on developing efficient strategies to contain the pandemic and minimize loss to the kiwifruit industry. Chemical and biological control options, orchard management and breeding programmes are being employed in this global effort. Synergy between different disease control strategies has been recognized as important. Phytotoxicity, resistance development and regulatory measures in certain countries restrict the use of copper compounds and antibiotics, which are otherwise the mainstay chemicals against bacterial plant diseases. Therefore, because of the limitations of existing chemicals, it is important to develop novel chemical controls against Psa. Antimicrobial peptides, which are attractive alternatives to conventional antibiotics, have found promising applications in plant disease control and could contribute to expanding the chemical control tool box against Psa. This review summarizes all chemical compounds trialled so far against Psa and provides thoughts on the development of antimicrobial peptides as potential solutions for the future.

Efficacy of different chemical and biological products in the control of Pseudomonas syringae pv. actinidiae on kiwifruit

“…Hayward, by using chemical and biological products. Chemical control of bacterial diseases, and particularly of Psa, is highly dependent on spraying antibiotics, such as streptomycin, or copper formulations (Cameron and Sarojini 2014). In Europe the use of streptomycin for control of plant pathogens is not legal, so copper formulations remain the main management strategy for crop protection against bacterial diseases (Gullino and Brunelli 2012).…”

High-Throughput Chemical Screening Identifies Compounds that Inhibit Different Stages of the Phytophthora agathidicida and Phytophthora cinnamomi Life Cycles

“…For example, copper spraying has become a significant component of the kiwifruit industry’s spray program for providing protection against infection by Pseudomonas syringae pv. actinidiae (Cameron and Sarojini, 2014; Gould et al, 2015). Similarly, copper fungicides are widely used by the New Zealand forestry industry for control of dothistroma needle blight (Bulman et al, 2013) and they have recently been shown to be effective against Phytophthora pluvialis (Rolando et al, 2016).…”

Xanthomonas arboricola disease of hazelnut: current status and future perspectives for its management

“…Products such as harpins that activate plant defence and induce resistance, and polysaccharides such as chitosan (Dong et al, 1999;Reglinski et al, 2011) have been used to control different bacterial pathogens. In addition, terpenes (Ferrante & Scortichini, 2010) and antimicrobial peptides (Cameron & Sarojini, 2014) are reported to control phytopathogenic Pseudomonas syringae to some extent. Several other chemicals have been proposed and used for the control of bacterial diseases.…”