Inhibitors of Asexual Reproduction of the Plant Pathogen Phytophthora from Tomato Juice: Structure-Activity Relationships and Transcriptome Analysis

J Agric Food Chem. 2022 Oct 12;70(40):12878-12884. doi: 10.1021/acs.jafc.2c05556. Epub 2022 Oct 3.

Abstract

Phytophthora is a genus of fungus-like microorganisms that damages important crops, such as potatoes and tomatoes. Its asexual reproduction, which results in the production of numerous motile zoospores, is the cause of quick and severe outbreaks and crop damage. The search for substances that selectively inhibit the asexual reproduction of Phytophthora led to the isolation of the known natural products naringenin and flazin from tomato juice. They inhibit the sporangia formation of Phytophthora capsici at IC50 values of 8.8 and 7.2 μM. The study of the structure-activity relationship of 11 flavonoids, including naringenin, demonstrated that genistein was the most active (IC50 = 4.6 μM) and flavonols/flavanonols possessing the 3-hydroxy function showed little activity (IC50 = from 100 to >1000 μM). To demonstrate the mechanism of asexual reproduction inhibition by genistein, transcriptome analysis was carried out, which revealed the downregulation of some genes related to cell differentiation. The results suggest that certain flavonoids are environmentally benign agents that could be used to protect agricultural products from Phytophthora pathogens.

Keywords: RNA-seq; flazin; genistein; plant pathogen; sporangia.

MeSH terms

  • Biological Products*
  • Flavonols
  • Gene Expression Profiling
  • Genistein
  • Lycopersicon esculentum* / genetics
  • Phytophthora* / physiology
  • Plant Diseases
  • Reproduction, Asexual
  • Structure-Activity Relationship

Substances

  • Biological Products
  • Flavonols
  • Genistein