Broad-spectrum antimicrobial activity of volatile organic compounds from endophytic Pseudomonas putida BP25 against diverse plant pathogens

• Published in: Biocontrol science and technology Vol. 29; no. 11; pp. 1069 - 1089
• Main Authors: Agisha, Valiya Nadakkakath, Kumar, Aundy, Eapen, Santhosh Joseph, Sheoran, Neelam, Suseelabhai, Rajamma
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 02.11.2019; Taylor & Francis Ltd
• Subjects: Agricultural management; Antiinfectives and antibacterials; Antimicrobial activity; Antimicrobial agents; dimethyl trisulphide; Disease control; Endophyte; Endophytes; Fungi; Nematodes; Organic chemistry; Organic compounds; Parasitic diseases; Pathogens; Plant diseases; Pseudomonas putida; Pyrazine; Pyrazines; VOCs; Volatile compounds; Volatile organic compounds; Volatiles
• ISSN: 0958-3157; 1360-0478
• DOI: 10.1080/09583157.2019.1657067

Black pepper endophytic Pseudomonas putida BP25 produced diverse antimicrobial volatile organic compounds having potential for plant disease management. Chemically synthesised volatiles such as 2, 5-dimethyl pyrazine; 2-methyl pyrazine; dimethyl trisulphide; 2-ethyl 5-methyl pyrazine; and 2-ethyl 3, 6-dimethyl pyrazine showed inhibitory activity against oomycete pathogens, Phytophthora capsici & Pythium myriotylum; fungal pathogens, Rhizoctonia solani, Colletotrichum gloeosporioides, Athelia rolfsii, Gibberella moniliformis & Magnaporthe oryzae; bacterial pathogen, Ralstonia pseudosolanacearum and plant parasitic nematode, Radopholus similis. Among them, dimethyl trisulphide completely inhibited oomycete and fungal pathogens as well as R. similis at a concentration of 2.65 µg cm −3 under in vitro conditions. Pyrazines suppressed Phytophthora lesions on shoot cuttings of black pepper upon in planta volatile treatment. Dimethyl trisulphide was the only compound that exhibited soil fumigant activity against P. capsici, R. solani and A. rolfsii (6.25 µg cm −3 ), C. gloeosporioides and G. moniliformis (12.5 µg cm −3 ), and R. similis (50 µg cm −3 ). Altogether, endophytic Pseudomonas putida BP25 and its volatile organic compounds offer an alternative strategy for eco-friendly disease management in agriculture.