Effect of two liquid formulations based on Brassica carinata co-products in containing powdery mildew on melon

•Two entirely bio-based liquid formulations were tested against powdery mildew.•Brassica carinata seed based products foil powdery mildew on melon.•The power of a bio-based product was akin to a rife chemical commercially available.•Both formulations are interesting as alternatives to agrochemicals.

Two liquid bio-based formulations were characterized and evaluated for powdery mildew (Podosphaera xanthii) control on melon. The new products were based on oil and defatted seed meals of Brassica carinata at different concentrations, formulated according to the patented procedure PCT WO 2006/136933. The abilities of innovative emulsions to release the bioactive molecule allyl-isothiocyanate and to contain its dispersal in the air were evaluated in lab conditions. In the years 2012 and 2013, trials on plants naturally infected with P. xanthii were performed at Monsampolo del Tronto (Ascoli Piceno, Italy) in open field. Both formulations showed disease control properties. In particular, the formulation with the higher concentration of oil and defatted seed meal gave results statistically not different from Topas 10 EC, a chemical pesticide widely applied for melon defence both in greenhouse and open field, that was inserted as control. Two weeks after the first treatment no leaves were presenting lesions covering more than 60% of their surface and the attack index, which takes into account both the area covered by lesions and the number of infected leaves, was halved if compared to the untreated control. The new bio-based formulations could thus be considered of great interest both for conventional and organic farming in the control of powdery mildew on melon.