Extracts of Ulva lactuca Induce Responses against Penicillium digitatum on Oranges

Penicillium digitatum causes severe damage to postharvest and stored citrus fruits, making it necessary seek acceptable solutions limiting environmental sanitary impacts. The seaweed liquid extracts (SLEs) obtained from the green macroalgae Ulva lactuca have previously shown anti-fungal activities towards mold due P. digitatum. Moreover, treatment with aqueous ethanolic had an influence on disease incidence lesion severity wounded oranges “Valentia late”. Therefore, we studied abilities of U. chlorophyll a (as standard) activate defense mechanisms in oranges. analyses showed modifications protein concentrations β-1,3-glucanase peroxidase orange tissues, maximum activity level reached at 72 h after treatments. It appears that SLEs were able fight infections absence direct contact pathogen, reflecting induction host resistance is also probable mode action. fractions are rich a, polyphenols, organic acids ulvans, which might be key molecules involved mechanism oranges’ albedo. use these natural substances could alternative way control rot.