Hop polyphenols in relation to Verticillium wilt resistance and their antifungal activity

Berne, Sabina (author), Kovačević, Nataša (author), Kastelec, Damijana (author), Javornik, Branka (author), Radišek, Sebastjan (author)

(1) Background: Verticillium wilt (VW) of hop is a devastating disease caused by the soil-borne fungi Verticillium nonalfalfae and Verticillium dahliae. As suggested by quantitative trait locus (QTL) mapping and RNA-Seq analyses, the underlying molecular mechanisms of resistance in hop are complex, consisting of preformed and induced defense responses, including the synthesis of various phenolic compounds. (2) Methods: We determined the total polyphenolic content at two phenological stages in roots and stems of 14 hop varieties differing in VW resistance, examined the changes in the total polyphenols of VW resistant variety Wye Target (WT) and susceptible Celeia (CE) on infection with V. nonalfalfae, and assessed the antifungal activity of six commercial phenolic compounds and total polyphenolic extracts from roots and stems of VW resistant WT and susceptible CE on the growth of two different V. nonalfalfae hop pathotypes. (3) Results: Generally, total polyphenols were higher in roots than stems and increased with maturation of the hop. Before flowering, the majority of VW resistant varieties had a significantly higher content of total polyphenols in stems than susceptible varieties. At the symptomatic stage of VW disease, total polyphenols decreased in VW resistant WT and susceptible CE plants in both roots and stems. The antifungal activity of total polyphenolic extracts against V. nonalfalfae was higher in hop extracts from stems than those from roots. Among the tested phenolic compounds, only p-coumaric acid and tyrosol markedly restricted fungal growth. (4) Conclusions: Although the correlation between VW resistance and total polyphenols content is not straightforward, higher levels of total polyphenols in the stems of the majority of VW resistant hop varieties at early phenological stages probably contribute to fast and efficient activation of signaling pathways, leading to successful defense against V. nonalfalfae infection.

• Language: English
• Keywords: Humulus lupulus, hop extract, plant disease resistance, antifungal, p-coumaric acid, tyrosol
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 21 str.
• Numbering: Vol. 9, iss. 10, art. 1318
• PID: 20.500.12556/RUL-134467
• UDC: 577.2
• ISSN on article: 2223-7747
• DOI: 10.3390/plants9101318
• COBISS.SI-ID: 31470595
• Publication date in RUL: 17.01.2022

Record is a part of a journal

• Title: Plants
• Shortened title: Plants
• Publisher: MDPI
• ISSN: 2223-7747
• COBISS.SI-ID: 523345433

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 06.10.2020

Secondary language

• Language: Slovenian
• Keywords: Humulus lupulus, hmelj, Verticillium nonalfalfae, Verticillium dahliae, verticilijska uvelost, fenolne spojine, interakcija rastlina-patogen, kumarna kislina, odpornost rastlin, odpornost na bolezni

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0077
• Name: Kmetijske rastline - genetika in sodobne tehnologije