a b s t r a c t
Currently there is a lack of effective seed treatments for bacterial pathogens, with Cu-based compounds (the only chemical treatments
permitted under organic farming standards) only providing
control. The aim of this study was to quantify the effect of alternative treatments for the control of bacterial canker (Clavibacter
michiganensis subsp. michiganensis), a major seed-borne
bacterial tomato. Treatments assessed were acidified nitrite (a treatment previously shown to control the seed-borne fungal disease Didymella lycopersici), antagonistic strains of Bacillus spp. and compost extracts, which were not previously evaluated as treatments for seed-borne diseases. Efficacy of treatments was determined in a
seed disinfection assay. Ten-minute immersion of seed in
300 mmol l−1acidified nitrite resulted in 98% being pathogen free. Copper hydroxide, certain strains of Bacillus spp. and all compost extracts resulted in100%pathogen free disease seed.partial in