title: Biochar-amended potting medium reduces the susceptibility of rice to root-knot nematode infections.
abstract: BACKGROUND
  Biochar is a solid coproduct of biomass pyrolysis, and soil amended with biochar has been shown to enhance the productivity of various crops and induce systemic plant resistance to fungal pathogens. The aim of this study was to explore the ability of wood biochar to induce resistance to the root-knot nematode (RKN) Meloidogyne graminicola in rice (Oryza sativa cv. Nipponbare) and examine its histochemical and molecular impact on plant defense mechanisms.
  
  
  RESULTS
  A 1.2 % concentration of biochar added to the potting medium of rice was found to be the most effective at reducing nematode development in rice roots, whereas direct toxic effects of biochar exudates on nematode viability, infectivity or development were not observed. The increased plant resistance was associated with biochar-primed H2O2 accumulation as well as with the transcriptional enhancement of genes involved in the ethylene (ET) signaling pathway. The increased susceptibility of the Ein2b-RNAi line, which is deficient in ET signaling, further confirmed that biochar-induced priming acts at least partly through ET signaling.
  
  
  CONCLUSIONS
  These results suggest that biochar amendments protect rice plants challenged by nematodes. This priming effect partially depends on the ET signaling pathway and enhanced H2O2 accumulation.
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium. wkhuang2002@163.com.|State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, 100193, Beijing, P. R. China. wkhuang2002@163.com.
authors.forename: Wen-kun
authors.initials: WK
authors.lastname: Huang
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium. ji.hongli@ugent.be.|Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Jingjusi Road 20, 610066, Chengdu, P. R. China. ji.hongli@ugent.be.
authors.forename: Hong-li
authors.initials: HL
authors.lastname: Ji
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium. godelieve.gheysen@ugent.be.
authors.forename: Godelieve
authors.initials: G
authors.lastname: Gheysen
authors.affiliation: Plant Sciences Unit - Plant Protection, Institute for Agricultural and Fisheries Research (ILVO), Burg. van Gansberghelaan 96, 9820, Merelbeke, Belgium. jane.debode@ilvo.vlaanderen.be.
authors.forename: Jane
authors.initials: J
authors.lastname: Debode
authors.affiliation: Department of Molecular Biotechnology, Ghent University, Coupure Links 653, B-9000, Ghent, Belgium. Tina.kyndt@ugent.be.
authors.forename: Tina
authors.initials: T
authors.lastname: Kyndt
mesh_terms: D000818:Animals; D002606:Charcoal / Q000494:pharmacology*; D012275:Oryza / Q000254:growth & development / Q000276:immunology / Q000469:parasitology*; D010935:Plant Diseases / Q000469:parasitology / Q000517:prevention & control*; D012987:Soil / Q000469:parasitology*; D014431:Tylenchoidea / Q000187:drug effects* / Q000502:physiology
chemical_list: D012987:Soil; C540010:biochar; D002606:Charcoal