Evaluation of electrolysed water based solutions as a sustainable approach to control phytopathogenic fungi

• EW inhibited the spore germination of multiple fungi, including B. cinerea, A. solani, A. brassicicola, C. truncatum , and F. solani . • EW reduced the incidence and severity of diseases in broccoli and tomato seedlings infected by A. brassicicola and A. solani , respectively. • In greenhouse trials, EW treatments at 50 ppm showed disease severity reductions comparable to commercial fungicides. • EW did not cause phytotoxicity in plants at concentrations up to 500 ppm. • EW preparation implies less environmental impact and offers lower cost that conventional treatment. Phytopathogenic fungi and oomycetes pose significant threats to horticultural production. Usually, biocidal substances are used to control these pathogens despite their environmental impact and economic expenses. Electrolysed water (EW) products have emerged as a potential sustainable alternative for disinfection purposes. This study evaluated the effectiveness of 11 EW products (5 of them containing zeolite) with a pH of 4.5 and chlorine concentrations ranging from 50 to 500 ppm free available chlorine (FAC) as biocides against various fungi and oomycetes: Alternaria brassicicola, A. solani, Botrytis cinerea, colletotrichum truncatum, Fusarium solani, Pythium aphanidermatum, P. ultimum, Rhizoctonia solani and Sclerotinia sclerotiorum. In vitro tests demonstrated that EW inhibited the spore germination of fungi and was particularly effective against the mycelial growth of B. cinerea, P. aphanidermatum , and P. ultimum. In vivo tests on seedlings with EW of 100 ppm FAC offered a reduction in disease incidence and severity by approximately 70 % of A. brassicicola over B. oleracea (broccoli) and A. solani over S. lycopersicum (tomato). However, in greenhouse conditions, EW treatments at 50 ppm free available chlorine (FAC) provided only a limited reduction in disease severity, comparable to commercial fungicides such as difenoconazole. Life cycle analysis under the ReCiPe method revealed that the endpoint environmental impact of EW generation is nearly 20 times lower than that of conventional pesticides (51 times for global warming), if the reduction in diesel costs derived from application machinery is considered. Therefore, EW shows potential as a sustainable and profitable water based alternative for controlling fungi and oomycetes.