title: EndophyticTrichoderma gamsiiYIM PH30019: a promising biocontrol agent with hyperosmolar, mycoparasitism, and antagonistic activities of induced volatile organic compounds on root-rot pathogenic fungi ofPanax notoginseng.
abstract: BACKGROUND
  Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems.Trichodermaspecies have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus,Trichoderma gamsiiYIM PH30019, from healthyPanax notoginsengroot was investigated for its biocontrol potential.
  
  
  METHODS
  In vitrodetached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy ofT. gamsiiYIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations.
  
  
  RESULTS
  The results indicated thatT. gamsiiYIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%.T. gamsiiYIM PH30019 displayed antagonistic activities against the pathogenic fungi ofP.notoginsengvia production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity.T. gamsiiYIM PH30019 was able to improve the seedlings' emergence and protectP. notoginsengplants from soil-borne disease in the continuous cropping field tests.
  
  
  CONCLUSIONS
  The results suggest that the endophytic fungusT. gamsiiYIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions betweenTrichodermaand phytopathogens.
authors.affiliation: School of Energy and Environment Science, Yunnan Normal University, Kunming, China; Key Laboratory of Microbial Diversity in South West China of Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, China.
authors.forename: Jin-Lian
authors.initials: JL
authors.lastname: Chen
authors.affiliation: School of Energy and Environment Science, Yunnan Normal University, Kunming, China.
authors.forename: Shi-Zhong
authors.initials: SZ
authors.lastname: Sun
authors.affiliation: Key Laboratory of Microbial Diversity in South West China of Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, China.
authors.forename: Cui-Ping
authors.initials: CP
authors.lastname: Miao
authors.affiliation: School of Energy and Environment Science, Yunnan Normal University, Kunming, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Wu
authors.affiliation: Key Laboratory of Microbial Diversity in South West China of Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, China.
authors.forename: You-Wei
authors.initials: YW
authors.lastname: Chen
authors.affiliation: Key Laboratory of Microbial Diversity in South West China of Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, China.
authors.forename: Li-Hua
authors.initials: LH
authors.lastname: Xu
authors.affiliation: School of Energy and Environment Science, Yunnan Normal University, Kunming, China.
authors.forename: Hui-Lin
authors.initials: HL
authors.lastname: Guan
authors.affiliation: Key Laboratory of Microbial Diversity in South West China of Ministry of Education and Laboratory for Conservation and Utilization of Bio-Resources, Yunnan Institute of Microbiology, Yunnan University, Kunming, China.
authors.forename: Li-Xing
authors.initials: LX
authors.lastname: Zhao
keywords: Panax notoginseng; Trichoderma gamsii; antagonistic activity; biocontrol agents; mycoparasitism