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Background: The antimicrobial activity of allyl-isothiocyanate (AITC) on plant pathogens is well known and has already been demonstrated in the strawberry with respect to Botritis cinerea fungal infection using postharvest biofumigation. In the present study, vapours of 0.08 mg L -1 of Brassica meal-derived AITC were applied to strawberry to assess its effect on fruit nutraceutical and biochemical parameters after 2 days of storage at 20 °C and 90% relative humidity., Results: Allyl-isothiocyanate showed no detrimental effect on final strawberry quality, anti-oxidant properties or ascorbic acid content. By contrast, an increased amount of asparagine and a higher ascorbate and glutathione redox potential were registered in the fruit soon after treatment. A reversible glutathione depletion action of AITC was also observed. Finally, total AITC residues in treated strawberry were quantified and a relatively high amount of AITC-adducts was found in fruit tissues., Conclusion: The findings of the present study not only confirm the high potentiality of biofumigation with respect to extending the shelf-life of fruit, but also provide some insight regarding the mechanisms of action of AITC at the cellular level as a possible elicitor of fruit protective responses. Nevertheless, the nature of the AITC-adducts formed in fruit tissues needs further attention to enable a health and safety assessment of the final fruit. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)

Abstract: Biofumigation by Brassicaceae green manure or seed meal incorporation into soil is an ecological alternative to chemical fumigation against soil-borne pathogens, based on the release of glucosinolate-derived compounds. This study aimed at investigating the tolerance of the beneficial fungus Trichoderma to these compounds in view to combined utilization with Brassica carinata seed meal (BCSM). Forty isolates of Trichoderma spp. were tested in vitro for tolerance to toxic volatiles released by BCSM and in direct contact with the meal. They were found to be generally less sensitive than the assayed pathogens (Pythium ultimum, Rhizoctonia solani, Fusarium oxysporum), even if a fungistatic effect was observed at the highest dose (10μmole of sinigrin). Most of them also were able to grow on BCSM and over the pathogens tested. A preliminary experiment of integrating BCSM with Trichoderma in soil was carried out under controlled conditions with the patho-system P. ultimum—sugar beet. BCSM incorporation increased pathogen population, but reduced disease incidence, probably due to indirect mechanisms. The greatest effect was achieved when BCSM was applied in combination with Trichoderma, regardless of meal ability to release isothiocyanate. These findings suggest that disease control can be improved by this integrated approach. This study also highlighted that a reduction of allyl-isothiocyanate concentration in soil could occur due to the activity of some Trichoderma isolates. This effect could protect resident or introduced Trichoderma isolates from depressing effects due to the biocidal compounds, but, on the other hand, could reduce the efficacy of biofumigation against target pathogens. [Copyright &y& Elsevier]