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This study investigated the antifungal activity of a number of pomegranate genotypes. Since the main compound of pomegranate extract is punicalagin, an important substance involved in antifungal and antimicrobial activity, we analyzed the contents of punicalagin (α and β) in 21 different pomegranate genotypes. Ellagic acid content, total phenolic content, acidity and pH were also determined. This work allowed us to determine which genotypes of pomegranate can be used to obtain extracts with the highest content of punicalagin, with the goal of developing a green alternative to synthetic pesticides. To improve the extraction system from pomegranate peel fruits, several different solvents were tested. All the pomegranate genotypes tested showed antifungal activity; some genotypes were able to almost completely inhibit the fungus, while others had very low inhibitory activity. Research results also showed that the use of water as a solvent for extraction is very effective, especially when it is combined with ethanol. This is very important for the practical use of the extracts since water is economical and environmentally friendly. The research showed that among the genotypes there is also great variability regarding the chemical parameters. Genotypes with a high phenolic and punicalagin content were significantly correlated with antifungal activity. All the other chemical parameters (pH, titratable acidity and ellagic acid content) were not correlated with antifungal activity. The results obtained indicate that the fruits of some pomegranate genotypes could be used to obtain extracts very rich in punicalagins and that these substances could be used as an alternative to synthetic products to control plant disease and improve the quality of the plant products, avoiding the impact of synthetic chemicals on the environment.

The present paper describes the antifungal activity of some plant extracts on the development of Fusarium oxysporum f.sp. lycopersici. The best extracts were selected to be tested as a phytofungicide to control crop diseases, with the ultimate goal of developing a green alternative to synthetic fungicides. Using the conidia germination assay, of the 24 plant extracts tested, 15 reduced conidia germination and 6 completely inhibited germination. Extracts of Rivina humulis, Brassica carinata, Brunfelsia calyicina, Salvia guaranitica and Punica granatum showed good antifungal activity. The relationship between total phenolic content (TPC) in each plant extract tested and the percentage of mycelial growth inhibition showed a significant correlation (R2 = 0.69), while no correlation was found between total flavonoid content (TFC) and percentage mycelial growth inhibition. Among all extracts tested, Punica granatum and Salvia guaranitica showed the best inhibitory effect against Fusarium oxysporum f.sp. lycopersici . Our results indicate that plant extracts with a good antifungal activity generally had a high level of total polyphenolic content and titratable acidity, and low values of pH.

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In an attempt to reduce the use of synthetic fungicides, extensive investigations into the possible exploitation of plant compounds as natural commercial products were performed. The present paper describes the antifungal activity of botanic extracts on the development of <i>Fusarium oxysporum</i>, f.s.p. <i>lycopersici</i>. The tests <i>in vitro</i> were carried out in a multi-well plate assay. The tested plants were classified based on the optical density reached by germinating conidia 24, 48 and 72 hours after inoculation. Among 500 plant species tested, about 84% did not exert significant inhibition, 7.6% showed low inhibition, 5.2% had an intermediate level of antifungal activity, and only 3% inhibited fungal germination completely. These findings suggest that some botanic extracts tested possess antifungal activities against <i>Fusarium oxysporum</i> and could be used as potential antifungal agents for the control of fungal plant diseases