β-Aminobutyric Acid and Powdery Mildew Infection Enhanced the Activation of Defense-Related Genes and Salicylic Acid in Cucumber ( Cucumis sativus L.)

• Published in: Genes Vol. 14; no. 11; p. 2087
• Main Authors: Kim, Ja-Yoon, Kang, Hee-Wan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01.11.2023
• Subjects: 3-Aminobutyric acid; Amino acids; Aminobutyrates - metabolism; Aminobutyrates - pharmacology; Antifungal agents; BABA; cucumber; Cucumbers; Cucumis sativus - microbiology; Defense; defense genes; Fungi; Gene expression; Genes; Genetic aspects; Genetic research; Genetic transcription; Health aspects; Infections; Pathogens; Phenols; Plant diseases; Plant Diseases - genetics; Plant Diseases - microbiology; Powdery mildew; Salicylic acid; Salicylic Acid - metabolism; Salicylic Acid - pharmacology; Signal transduction; Sphaerotheca fusca; Spore germination; Transcription activation; South Korea; United States > US; BABA; defense genes; Sphaerotheca fusca; cucumber
• ISSN: 2073-4425; 2073-4425
• DOI: 10.3390/genes14112087

Powdery mildew disease, caused by , is a major disease affecting cucumbers cultivated in greenhouses. This study was conducted to find defense genes induced by β-aminobutyric acid (BABA) and powdery mildew in cucumber. Disease severities of 25% and 5% were exhibited by the 2000 and 5000 mg/L BABA-treated cucumber, respectively. BABA did not affect the spore germination of the powdery mildew pathogen, showing that BABA is not an antifungal agent against the pathogen. In quantitative real-time PCR analysis, BABA-treated cucumber upregulated the transcriptional levels of the defense genes , , , , , Cs , , and in cucumber to maximum levels at 48 h, whereas reached maximum expression after 24 h, and further, salicylic acid (SA) levels were significantly increased in BABA-treated cucumber plants. In addition, the cucumber infected with powdery mildew underwent a 1.6- to 47.3-fold enhancement in the defense genes , , , , , , , and compared to heathy cucumber. These results suggest that the BABA-induced defense response is associated with SA signaling pathway-dependent systemic acquired resistance (SAR) in cucumber, which is involved in plant resistance mechanisms.