Effects of Neutral Electrolysed Water on tomato seeds artificially contaminated with Fusarium and Aspergillus

Abstract

Tomato is a globally important vegetable crop that is commonly infected by fungal pathogens. Current treatments to protect seeds can be unsafe to people and to the environment. Our aim was to investigate the effect of Neutral Electrolysed Water (NEW) on tomato seeds inoculated with isolates of Fusarium oxysporum, F. verticillioides, Aspergillus flavus or A. parasiticus. Seeds were exposed to a suspension of 2-2.5 x 10(6) conidia mL(-1) and then treated with NEW at 10, 40 and 60 mg L-1 of available chlorine content (ACC) for 5, 10, 15 and 20 minutes. Seeds were incubated for three days (Aspergillus isolates) and seven days (Fusarium isolates), after which total conidia were counted. NEW had a cytotoxic effect on conidia. The number of conidia of the four isolates was significantly reduced (P < 0.001) for the four NEW exposure times at 60 mg L-1 ACC compared with the control, with a trend of reduced conidia counts and viability as ACC increased. Seed germination and seed proximate compositions were not affected by NEW treatment. NEW is a feasible strategy to manage fungal infections in tomato seeds.