M Perazzolli, E Bozza, C Moser, I Pertot
Strains of non-pathogenic microorganisms can reduce plant diseases through activation of a plant-mediated defence mechanism known as induced systemic resistance (ISR). Scarce knowledge is available on the mechanisms of activation of ISR. Our aim was to characterize the systemic resistance against downy mildew activated in grapevine by the biocontrol agent Trichoderma harzianum T39. T. harzianum T39 reduced symptoms severity similarly to a benzothiadiazole (BTH) treatment. Optimal disease control was obtained when T. harzianum T39 was applied more than once before pathogen inoculation, whereas a single application of BTH was sufficient. In both cases a stronger effect was observed on leaves directly treated with the agents, but an efficient systemic protection was observed as well on untreated leaves. Expression analysis revealed the absence of PR2 and PR4 induction after elicitation and absence of priming after pathogen challenge.
M Perazzolli, E Bozza, C Moser, I Pertot
Strains of non-pathogenic microorganisms can reduce plant diseases through activation of a plant-mediated defence mechanism known as induced systemic resistance (ISR). Scarce knowledge is available on the mechanisms of activation of ISR. Our aim was to characterize the systemic resistance against downy mildew activated in grapevine by the biocontrol agent Trichoderma harzianum T39. T. harzianum T39 reduced symptoms severity similarly to a benzothiadiazole (BTH) treatment. Optimal disease control was obtained when T. harzianum T39 was applied more than once before pathogen inoculation, whereas a single application of BTH was sufficient. In both cases a stronger effect was observed on leaves directly treated with the agents, but an efficient systemic protection was observed as well on untreated leaves. Expression analysis revealed the absence of PR2 and PR4 induction after elicitation and absence of priming after pathogen challenge.