Secondary Metabolites of Pseudomonas aeruginosa LV Strain Decrease Asian Soybean Rust Severity in Experimentally Infected Plants

• Published in: Plants (Basel) Vol. 10; no. 8; p. 1495
• Main Authors: dos Santos, Igor Matheus Oliveira, Abe, Valéria Yukari, de Carvalho, Kenia, Barazetti, André Riedi, Simionato, Ane Stéfano, de Almeida Pega, Guilherme E., Matis, Sergio Henrique, Cano, Barbara Gionco, Cely, Martha Viviana Torres, Marcelino-Guimarães, Francismar Correa, Chryssafidis, Andreas Lazaros, Andrade, Galdino
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 21.07.2021; MDPI
• Subjects: Abiotic stress; Ammonia; Antiinfectives and antibacterials; ASR; bioactive compounds; Biosynthesis; Defense mechanisms; elicitors; Enzymes; Experiments; Flavonoids; Flowers & plants; Fungicides; Gene expression; Genes; Genetic engineering; Germination; glycine max; Infections; Lesions; Lignin; Metabolites; Methyltransferase; Pathogenesis; Pathogens; Phakopsora pachyrhizi; Phenylalanine; Plant bacterial diseases; Plant resistance; Proteins; Pseudomonas aeruginosa; rust control; Secondary metabolites; Soybeans; Spore germination
• ISSN: 2223-7747; 2223-7747
• DOI: 10.3390/plants10081495

Asian Soybean Rust (ASR), a disease caused by Phakopsora pachyrhizi, causing yield losses up to 90%. The control is based on the fungicides which may generate resistant fungi. The activation of the plant defense system, should help on ASR control. In this study, secondary metabolites of Pseudomonas aeruginosa LV strain were applied on spore germination and the expression of defense genes in infected soybean plants. The F4A fraction and the pure metabolites were used. In vitro, 10 µg mL−1 of F4A reduced spore germination by 54%, while 100 µg mL−1 completely inhibited. Overexpression of phenylalanine ammonia lyase (PAL), O-methyltransferase (OMT) and pathogenesis related protein-2 (PR-2; glucanases) defense-related genes were detected 24 and 72 h after soybean sprouts were sprayed with an organocopper antimicrobial compound (OAC). Under greenhouse conditions, the best control was observed in plants treated with 60 µg mL−1 of PCA, which reduced ASR severity and lesion frequency by 75% and 43%, respectively. Plants sprayed with 2 and 20 µg mL−1 of F4A also decreased severity (41%) and lesion frequency (32%). The significant reduction in spore germination ASR in plant suggested that the strain of these metabolites are effective against P. pachyrhizi, and they can be used for ASR control.