Silene uniflora Extracts for Strawberry Postharvest Protection

Halophytes are gaining considerable attention due to their applications in saline agriculture, phytoremediation, medicine, and secondary metabolite production. This study investigated the bioactive components present in Silene uniflora (sea campion) hydromethanolic extract, and their antimicrobial activity was evaluated both in vitro and ex situ against two strawberry phytopathogens, namely Botrytis cinerea (grey mold) and Colletotrichum nymphaeae (anthracnose fruit rot). The main identified phytochemicals were mome inositol, saturated fatty acid esters, and cyclotetracosane. In vitro tests demonstrated complete inhibition of the growth of B. cinerea and C. nymphaeae at extract concentrations of 1000 and 1500 mu g.mL(-1), respectively, with an activity comparable to that of fosetyl-Al and substantially higher than that of azoxystrobin. This activity was improved upon conjugation with chitosan oligomers (COS), yielding inhibition values of 750 and 1000 mu g.mL(-1). The COS-S. uniflora conjugate complexes were then tested as protective treatments for postharvest storage of strawberry fruit, resulting in high protection against artificially inoculated B. cinerea and C. nymphaeae at doses of 3750 and 5000 mu g.mL(-1), respectively. The reported results open the door to the valorization of this halophyte as a source of biorationals for strawberry protection.

Automated summary

Halophytes, such as Silene uniflora, have various applications in agriculture, phytoremediation, medicine, and secondary metabolite production. This study identified bioactive components in the hydromethanolic extract of S. uniflora and evaluated their antimicrobial activity against strawberry pathogens. The extract exhibited complete inhibition of the growth of the pathogens, surpassing the activity of common fungicides.