Volatilome of the maize phytopathogenic fungus Fusarium verticillioides: potential applications in diagnosis and biocontrol

• Published in: Pest management science
• Main Authors: Achimón, Fernanda, Pizzolitto, Romina P
• Format: Journal Article
• Language: English
• Published: England 02-10-2024
• Subjects: volatilome; diagnosis; Fusarium verticillioides; biocontrol; fumonisin B1
• ISSN: 1526-498X; 1526-4998; 1526-4998
• DOI: 10.1002/ps.8439

Fusarium verticillioides is a maize fungal phytopathogen and a producer of volatile organic compounds (VOCs) and fumonisin B
(FB
). Our aim was to study the volatilome, conidial production, ergosterol and FB
biosynthesis in maize cultures over a 30-day incubation period (5, 10, 15, 20, 25, 30 days post inoculation [DPI]). The effect of pure VOCs on the same parameters was then evaluated to study their potential role as biocontrol agents.
In total, 91 VOCs were detected, with volatile profiles being more similar between 5 and 10 DPI compared with 15, 20, 25 and 30 DPI. Ergosterol content increased steadily with incubation time, and three growth stages were identified: a lag phase (0 to 15 DPI), an exponential phase (15 to 20 DPI) and a stationary phase (20 to 30 DPI). The maximum concentration of FB
was detected at 25 (0.030 μg FB
/μg ergosterol) and 30 DPI (0.037 μg FB
/μg ergosterol), whereas conidial production showed a maximum value at 15 DPI (4.3 ± 0.2 × 10
conidia/μg ergosterol). Regarding pure VOCs, minimal inhibitory concentration values ranged from 0.3 mm for 4-hexen-3-one to 7.4 mm for 2-undecanone. Pure VOCs reduced radial growth, conidial production and ergosterol and FB
biosynthesis.
The marked resemblance between VOC profiles at 5 and 10 DPI suggests that they could act as early indicators of fungal contamination, particularly 4-ethylguaiacol, 4-ethyl-2-methoxyanisole, heptanol and heptyl acetate. On the other hand, their role as inhibitors of fungal growth and FB
biosynthesis prove their great potential as safer alternatives to control phytopathogenic fungi. © 2024 Society of Chemical Industry.