Isolation and molecular identification of Trichoderma species from wetland soil and their antagonistic activity against phytopathogens

• Published in: Physiological and molecular plant pathology Vol. 109; p. 101458
• Main Authors: Saravanakumar, Kandasamy, Wang, Myeong-Hyeon
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2020
• Subjects: antifungal properties; Biocontrol; biological control; Botrytis cinerea; ecosystems; energy; Enzymes; ethyl acetate; Fusarium graminearum; gas chromatography-mass spectrometry; hyperparasitism; Macrophomina phaseolina; metabolism; Metabolites; mycoparasites; nonribosomal peptides; Phytopathogens; plant pathogens; plant pathology; polyketide synthases; South Korea; Trichoderma; wetland soils; wetlands; South Korea; Trichoderma; Enzymes; Phytopathogens; Metabolites; Biocontrol
• ISSN: 0885-5765; 1096-1178
• DOI: 10.1016/j.pmpp.2020.101458

Trichoderma species are known to protect the plants from pathogen infections through multifunctions, such as secondary metabolism, mycoparasitism, hyperparasitism, nutrient competition, enzymes and induced systemic resistance (ISR). Herein, we isolated a total of 18 Trichoderma strains divided to nine species such as T. atroviride, T. virens, T. velutinum, T. harzianum, T. asperellum, T. koningiopsis, T. aureoviride, H. lixii, and T. koningii from the soils samples, collected from the wetland ecosystem of South Korea. These strains were screened against the pathogens- Macrophomina phaseolina (MP), Fusarium graminearum (FG), and Botrytis cinerea (BC) - by in vitro antagonistic assay. Amongst, T. aureoviride (SKCGW013) showed higher antagonistic activity against the targeted pathogens than other isolates did. The strain SKCGW013 was further used for extraction, purification and analysis of the metabolites by column chromatography (CC) and gas chromatography mass spectroscopy (GC-MS). The expression of secondary metabolites regulatory genes of non-ribosomal peptide synthetase (NRPS), polyketide synthase (PKS) were studied by RT-qPCR. The results showed the presence of eight dominant compounds in the ethyl acetate fraction of the strain SKCGW013 and these compound were then screened by molecular modeling method against phytopathogens. In addition, RT-qPCR study revealed the significant expression of metabolites related genes. Further molecular docking study showed that the compounds from strain SKCGW13 synergistically inhibited the targeted pathogens. Among the compounds - 2H-Pyran, 3-bromo-2-butoxytetrahydro-, cis - exhibited high docking inhibitory energy against the targeted proteins, FgSwi6 and Bcpmr1 from FG and BC respectively. Overall, this study concluded that T. aureoviride SKCGW013 was an excellent source for discovery of novel metabolites as bio-control agents as evident by its metabolite profile with antifungal activity. [Display omitted] •This work reported the potent biocontrol strain from wetland soil of Republic of Korea.•A total of nine Trichoderma species was isolated with potent biocontrol properties.•T. auroviride (SKCGW013) inhibited the growth of various phytopathogens.•Metabolites from the T. auroviride induced biocontrol activity synergistically.