In vitro EFFICACY OF HERBAL PLANT EXTRACTS ON SOME PHYTOPATHOGENIC FUNGI

Crops are subject to yield losses caused by the presence of pests whose species and population diversity are changing with climate warming. The use of agrochemicals is still the most effective method of plant protection against diseases and pests. However, the intensive use of pesticides in some EU countries makes it necessary to search for alternative methods that can be applied in plant protection for consumer and envi-ronmental safety. The aim of the study was the laboratory evaluation of the fungistatic effect of extracts of herbal plants occurring in natural state in Poland: horseradish (Armoracia rusticana L.), yarrow (Achillea millefolium L.) and tansy (Tanacetum vulgare L.) on selected polyphagic phytopathogenic fungi (Alternaria alternata, Botrytis cinerea, Colletotrichum coccodes and Fusarium oxysporum). In this study, 5%, 10% and 20% concentrations of herbal water-extract extracts were applied to evaluate their effects on linear growth of fungi and inhibition of their growth relative to control. Total content of polyphenols and flavonoids was assessed in the extracts using spectrophotometry, and their antioxidant activity by applying the synthetic DPPH radical. The plant extracts of tansy and yarrow leaves were characterized by a higher content of poly -phenols and flavonoids compared to horseradish leaf extracts; they also had a higher antioxidant activity. Plant extracts inhibited the growth of fungi to a different extent, depending on the species of fungus, type of extract, its concentration and duration of action. The strongest fungistatic effect was recorded for tansy and yarrow extracts, while the weakest for the extract of horseradish leaves. Plant extracts showed the weakest effect against Botrytis cinerea, inhibiting the development of this fungus only during the first days of the experiment. The present research is a preliminary study that will be used in the further to develop a biological preparation for the protection of agricultural and horticultural plants against fungal pathogens.

Automated summary

With climate warming, the species and population diversity of pests affecting crops are changing, leading to yield losses. The excessive use of pesticides in some EU countries necessitates the search for alternative methods for plant protection. This study evaluated the fungistatic effect of herbal plant extracts (horseradish, yarrow, and tansy) on polyphagic phytopathogenic fungi. The results showed that tansy and yarrow extracts exhibited strong fungistatic effects, while horseradish leaf extracts had weaker effects. This preliminary research provides a basis for developing biological preparations to protect agricultural and horticultural plants against fungal pathogens.