Volatile Organic Compound from Trichoderma asperelloides TSU1: Impact on Plant Pathogenic Fungi.

Kitsada Pitija,Putarak Chomnunti,Prisana Wonglom,Anurag Sunpapao,Narit Thaochan,Nakarin Suwannarach,On-Uma Ruangwong,Jaturong Kumla

doi:10.3390/jof7030187

Abstract

Soil microorganisms are well studied for their beneficial effects on plant growth and their impact on biocontrol agents. The production of volatile antifungal compounds emitted from soil fungi is considered to be an effective ability that can be applied in biofumigants in the control of plant diseases. A soil fungus, Trichoderma asperelloides TSU1, was isolated from flamingo flower cultivated soil and identified on the basis of the morphology and molecular analysis of the internal transcribed spacer (ITS), rpb2, and tef1-α genes. To test T. asperelloides TSU1-produced volatile organic compounds (VOCs) with antifungal activity, the sealed plate method was used. The VOCs of T. asperelloides TSU1 inhibited the mycelial growth of fungal pathogens that were recently reported as emerging diseases in Thailand, namely, Corynespora cassiicola, Fusarium incarnatum, Neopestalotiopsis clavispora, N. cubana, and Sclerotium rolfsii, with a percentage inhibition range of 38.88–68.33%. Solid-phase microextraction (SPME) was applied to trap VOCs from T. asperelloides TSU1 and tentatively identify them through gas chromatography–mass spectrometry (GC/MS). A total of 17 compounds were detected in the VOCs of T. asperelloides TSU1, and the dominant compounds were identified as fluoro(trinitro)methane (18.192% peak area) and 2-phenylethanol (9.803% peak area). Interestingly, the commercial 2-phenyethanol showed antifungal activity against fungal pathogens that were similar to the VOCs of T. asperelloides TSU1 by bioassay. On the basis of our study’s results, T. asperelloides TSU1 isolated from soil displayed antifungal abilities via the production of VOCs responsible for restricting pathogen growth.

Highlights

Soil is an important source of beneficial microorganisms
The results show that T. asperelloides TSU1 released volatile organic compounds (VOCs) with antifungal abilities for the inhibition of fungal pathogen growth (Figure 3)
We found 2-PE to be a major peak by Solid-phase microextraction (SPME)/gas chromatography–mass spectrometry (GC/MS) analysis (Figure 5), and it was reported as an antifungal compound [44]. 2-Phenylethanol is a primary alcohol that is ethanol-substituted by a phenyl group at position 2

Summary

Introduction

Multiple soil fungi participate in the decomposition of organic matter to deliver plant nutrients [1]. They play an important role in plant protection against pathogens as biocontrol agents that influence soil health [2]. Trichoderma is the most important genus of beneficial microorganisms in agricultural soil, and it has been widely used in crop-plant production [5]. It is used as a natural-decomposition agent [6], plant-growth promoter [7], and as a biocontrol agent of plant diseases [8,9] and bioremediation [10]

Methods

Discussion

Conclusion