Potential of Salvia discolor Extract Against Common Agricultural Pathogens

Phytopathogenic fungi and bacteria pose a serious threat to global agriculture, leading to significant economic losses and potential health risks. Consequently, the search for natural alternatives to synthetic agrochemicals has garnered increasing scientific attention, with plant extracts emerging as promising environmentally friendly solutions. In this context, the surface extract of Salvia discolor, obtained using dichloromethane, was analyzed for its bioactive potential. Chemical profiling revealed a rich composition of terpenoids and flavonoids. The antimicrobial potential of the ground extract was evaluated against nine phytopathogenic fungi (Alternaria solani, Botrytis cinerea, Colletotrichum lindemuthianum, Fusarium solani, Fusarium oxysporum f. sp. lactucae race 1, Phoma betae, Phaeomoniella chlamydospora, Pythium dissotocum, and Stemphylium sp.), and two phytopathogenic bacteria (Clavibacter michiganesis subsp. michiganesis and Pectobacterium carotovorum subsp. carotovorum), selected from common pathogens of agricultural interest. Complete inhibition of P. chlamydospora at 1000 µg mL−1 and strong activity against P. dissotocum, F. solani and B. cinerea was observed, and low inhibition (<40%) against C. lindemuthianum and F. oxysporum f. sp. lactucae race 1. However, the extract showed promising results in the post-harvest protection of tomatoes against gray mold. Moderate antibacterial activity was seen against C. michiganensis subsp. michiganensis. These findings indicate that S. discolor extract has the potential to serve as an effective natural crop protection agent, though further optimization may be needed for broader application.