LAUSR

Abstract The efficacy of aerial parts’ organic extracts of diploid and mixoploid Trigonella foenum-graecum L. plants, harvested at three developmental stages (vegetative, flowering and fruiting) was evaluated for their antifungal activity against Fusarium oxysporum f. sp . radicis-lycopersici (FORL) and F. oxysporum f. sp . lycopersici (FOL). All tested extracts inhibited FORL and FOL mycelial growth. The organic extracts of diploid plants were found to be less toxic than mixoploid ones and this toxicity varied with the plant developmental stages. The diploids were most toxic, for the two strains, at the fruiting stage; however, mixoploids were more toxic at the vegetative stage for FOL and at flowering one for FORL. FOL was found to be more sensitive to fenugreek extracts when compared to FORL. LC–MS/MS analysis of methanolic extract of fenugreek aerial parts showed eleven different flavonol glycosides (quercetin, kaempferol and vitexin). Five novel components were identified, for the first time in fenugreek aerial parts, as kaempferol 3-O-β- d -glucopyranoside, kaempferol 7-O-glucoside, kaempferol 3-O-α- l -rhamnosyl (1→2) β- d -xyloside, kaempferol 7-O-β- d -glucopyranosyl (1–4) β- d -glucopyranoside and kaempferol 3-O-β-glucosyl (1→2) (6′-O-acetyl)-β- d -galactoside, along with other known compounds of this species. To operate with the maximum efficiency, the allelopathic potential of a given plant, our study showed that it would be advisable to identify the most productive developmental stage of allelochemicals. Similarly, it seems that mixoploidy would be a simple and effective biotechnology tool to improve (in quantity and quality) the allelochemicals’ production, since the extracts’ toxicity of diploid and mixoploid plants, was different.