New Nematotoxic Indoloditerpenoid Produced by Gymnoascus reessii za-130.
Chemical investigation of the fungal strain Gymnoascus reessii za-130, which was previously isolated from the rhizosphere of tomato plants infected by the root-knot nematode Meloidogyne incognita, led to the isolation and identification of a new indoloditerpenoid metabolite designated gymnoascole acetate. Its structure was established by spectroscopic methods including 1D- and 2D-NMR and MS analyses. Gymnoascole acetate demonstrated strong adverse effects on M. incognita second-stage juvenile (J2) viability; exposure to 36 μg/mL for 24 h induced 100% paralysis of J2 (EC50= 47.5 μg/mL). Gymnoascole acetate suppressed M. incognita egg hatch relative to controls by >90% at 133 μg/mL after 7 days of exposure. The numbers of root galls and J2 in both soil and roots were significantly reduced (p = 0.05) by treatment with 2-200 μg/mL gymnoascole acetate/kg soil, compared to untreated control plants; nematode suppression increased with gymnoascole acetate concentration. This study demonstrated the nematotoxicity of gymnoascole acetate and indicates that it might be a potential biobased component in integrated management of M. incognita.
Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Science , Beijing 100097, China.
Ting
T
Liu
Mycology and Nematology Genetic Diversity and Biology Laboratory, Agricultural Research Service, U.S. Department of Agriculture , Building 010A, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States.
Susan L F
SLF
Meyer
Mycology and Nematology Genetic Diversity and Biology Laboratory, Agricultural Research Service, U.S. Department of Agriculture , Building 010A, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States.
David J
http://orcid.org/0000-0002-2440-1365
DJ
Chitwood
Invasive Insect Biocontrol and Behavior Laboratory, Agricultural Research Service, U.S. Department of Agriculture , Building 007, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States.
Kamlesh R
KR
Chauhan
Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Science , Beijing 100097, China.
Dan
D
Dong
Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Science , Beijing 100097, China.
TaoTao
T
Zhang
Modern Research Center for Traditional Chinese Medicine, Beijing University of Chinese Medicine , Beijing 100029, China.
Jun
http://orcid.org/0000-0001-8243-5267
J
Li
Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Science , Beijing 100097, China.
Wei-Cheng
WC
Liu
D000818:Animals; D000969:Antinematodal Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001203:Ascomycota / Q000737:chemistry*; D004224:Diterpenes / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D018551:Solanum lycopersicum / Q000469:parasitology; D010935:Plant Diseases / Q000469:parasitology; D018517:Plant Roots / Q000469:parasitology; D014431:Tylenchoidea / Q000187:drug effects* / Q000254:growth & development
D000969:Antinematodal Agents; D004224:Diterpenes
Gymnoascus reessii; Meloidogyne incognita; fungus; gymnoascole acetate; indoloditerpenoid; nematicide; nematode; nematotoxin; terpenoid