Effect of juglone and other allelochemicals in walnut leaves on yield, quality and metabolites of snack cucumber (Cucumis sativus L.)

Medič, Aljaž (author), Zamljen, Tilen (author), Slatnar, Ana (author), Hudina, Metka (author), Grohar, Mariana Cecilia (author), Veberič, Robert (author)

The consumption of fresh vegetables has been consistently associated with numerous health benefits. However, several factors (such as allelochemicals) influence yield, quality, and metabolites, which inevitably affect the fruit quality and health benefits. The present study was conducted to investigate the yield, quality, metabolic responses, and potential toxicity of Cucumis sativus grown in juglone-containing soils. For the treatments, pure juglone (100 µM, 1 mM) and walnut leaf extracts (100 µM) in soil concentrations found in walnut orchards were used. A total of 36 phenolic compounds were identified and quantified in fruits, leaves, and roots using a mass spectrometer coupled with high-performance liquid chromatography. We concluded that juglone at a concentration of 100 µM or walnut leaf extract at the same juglone concentration does not affect the yield of C. sativus, while juglone at a concentration of 1 mM strongly affects it. In the case of juglone, juglone itself was found only in the roots of C. sativus, but not in the leaves or fruits, so C. sativus fruits are considered safe for cultivation in juglone-containing soils. However, this could prove problematic if the plants grown are tubers or root vegetables. The data suggest that juglone itself inhibits secondary metabolism in the plant, making it more susceptible to stress and pathogen attacks.

• Language: English
• Keywords: allelopathy, cucumber, naphthoquinones, juglone, 5-hydroxy-1, 4-naphthalenedione, phenolic compounds, toxic residue, HPLC, mass spectrometry, LC-MS, snack cucumber
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: BF - Biotechnical Faculty
• Publication status: Published
• Publication version: Version of Record
• Year: 2023
• Number of pages: 20 str.
• Numbering: Vol. 12, iss. 2, art. 371
• PID: 20.500.12556/RUL-143897
• UDC: 634.1/.7
• ISSN on article: 2304-8158
• DOI: 10.3390/foods12020371
• COBISS.SI-ID: 138199555
• Publication date in RUL: 18.01.2023

Record is a part of a journal

• Title: Foods
• Shortened title: Foods
• Publisher: MDPI
• ISSN: 2304-8158
• COBISS.SI-ID: 512252472

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.

Secondary language

• Language: Slovenian
• Keywords: alelopatija, kumare, juglon, fenolne spojine, masna spektrometrija

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P4-0013
• Name: Hortikultura