Plant Growth Promotion by Two Volatile Organic Compounds Emitted From the Fungus Cladosporium halotolerans NGPF1

Abstract

Microbial volatiles have beneficial roles in the agricultural ecological system, enhancing plant growth and inducing systemic resistance against plant pathogens without being hazardous to the environment. The interactions of plant and fungal volatiles have been extensively studied, but there is limited research specifically elucidating the effects of distinct volatile organic compounds (VOCs) on plant growth promotion. The current study was conducted to investigate the impact of VOCs from Cladosporium halotolerans NGPF1 on plant growth, and to elucidate the mechanisms for the plant growth-promoting (PGP) activity of these VOCs. The VOCs from C. halotolerans NGPF1 significantly promoted plant growth compared with the control, and this PGP activity of the VOCs was culture medium-dependent. Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) identified two VOC structures with profiles that differed depending on the culture medium. The two compounds that were only produced in potato dextrose (PD) medium were identified as 2-methyl-butanal and 3-methyl-butanal, and both modulated plant growth promotion and root system development. The PGP effects of the identified synthetic compounds were analyzed individually and in blends using N. benthamiana plants. A blend of the two VOCs enhanced growth promotion and root system development compared with the individual compounds. Furthermore, real-time PCR revealed markedly increased expression of genes involved in auxin, expansin, and gibberellin biosynthesis and metabolism in plant leaves exposed to the two volatile blends, while cytokinin and ethylene expression levels were decreased or similar in comparison with the control. These findings demonstrate that naturally occurring fungal VOCs can induce plant growth promotion and provide new insights into the mechanism of PGP activity. The application of stimulatory volatiles for growth enhancement could be used in the agricultural industry to increase crop yield.

Antifungal effects of volatile organic compounds produced by Trichoderma koningiopsis T2 against Verticillium dahliae

“…Fungal VOCs are a large group of carbon-based chemicals with low molecular weights, low polarities, low boiling points, and high vapor pressure ( Jiang et al, 2021 ). These characteristics provide VOCs with advantages over other secondary metabolites of a microbial nature, and these advantages include the abilities to travel long distances, to mediate interactions between organisms that are not in direct contact and to be perceived at low concentrations ( Yusnawan et al, 2021 ).…”

Physical and chemical characteristics of walnut (Juglans regia L.) kernels with different skin lightness

“…It was not clear how butanal, 2‐methyl and butanal, 3‐methyl are produced in plants. Several studies suggested that they were produced by fungi to promote plant growth (Jiang et al., 2021) or released during the heating of protein and fat (Bhatti et al., 2014). The higher concentration of pentanal in the Howard and Tulare dark kernels, compared to their respective light kernels, and butanal, 2‐methyl and butanal, 3‐methyl in all the dark kernels, indicated oxidation of lipid and possibly protein as well.…”

Antipathogenic Activities of Volatile Organic Compounds Produced by Bacillus velezensis LT1 against Sclerotium rolfsii LC1, the Pathogen of Southern Blight in Coptis chinensis

“…35 In recent years, more and more studies have shown that VOCs produced by beneficial microorganisms can not only inhibit the growth of plant pathogens but also promote plant growth. 36 B. velezensis has a strong rhizosphere colonization ability, and it has been reported to have a strong ability to inhibit pathogens and a broad-spectrum plant growth-promoting activities in multiple studies. 37 In this study, we report for the first time the inhibitory effect of B. velezensis against S. rolfsii.…”

“…The volatile organic compounds (VOCs) produced by microorganisms have desirable characteristics such as small molecular weight, low boiling point, low polarity, and lipophilicity, which enable VOCs to spread over long distances at very low concentrations, making them important media for the interaction between microorganisms and plants and animals . In recent years, more and more studies have shown that VOCs produced by beneficial microorganisms can not only inhibit the growth of plant pathogens but also promote plant growth B.…”