title: Arbuscular mycorrhizal fungal inoculation increases phenolic synthesis in clover roots via hydrogen peroxide, salicylic acid and nitric oxide signaling pathways.
abstract: Arbuscular mycorrhizal fungi can increase the host resistance to pathogens via promoted phenolic synthesis, however, the signaling pathway responsible for it still remains unclear. In this study, in order to reveal the signaling molecules involved in this process, we inoculated Trifolium repense L. with an arbuscular mycorrhizal fungus (AMF), Glomus mosseae, and monitored the contents of phenolics and signaling molecules (hydrogen peroxide (H(2)O(2)), salicylic acid (SA), and nitric oxide (NO)) in roots, measured the activities of l-phenylalanine ammonia-lyase (PAL) and nitric oxide synthase (NOS), and the expression of pal and chs genes. Results demonstrated that AMF colonization promoted the phenolic synthesis, in parallel with the increase in related enzyme activity and gene expression. Meanwhile, the accumulation of all three signaling molecules was also up-regulated by AMF. This study suggested that AMF increased the phenolic synthesis in roots probably via signaling pathways of H(2)O(2), SA and NO in a signaling cascade.
authors.affiliation: College of Horticulture, South China Agricultural University, Guangzhou, China.
authors.forename: Rui-Qin
authors.initials: RQ
authors.lastname: Zhang
authors.forename: Hong-Hui
authors.initials: HH
authors.lastname: Zhu
authors.forename: Hai-Quan
authors.initials: HQ
authors.lastname: Zhao
authors.forename: Qing
authors.initials: Q
authors.lastname: Yao
mesh_terms: D018533:Biomass; D018506:Gene Expression Regulation, Plant; D055137:Glomeromycota / Q000254:growth & development / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000032:analysis / Q000378:metabolism; D025301:Hyphae; D029902:Medicago / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D038821:Mycorrhizae / Q000254:growth & development / Q000502:physiology*; D009569:Nitric Oxide / Q000032:analysis / Q000378:metabolism; D019001:Nitric Oxide Synthase / Q000378:metabolism; D010636:Phenols / Q000032:analysis / Q000378:metabolism; D010650:Phenylalanine Ammonia-Lyase / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology; D018520:Plant Shoots / Q000235:genetics / Q000378:metabolism / Q000382:microbiology; D020156:Salicylic Acid / Q000032:analysis / Q000378:metabolism; D015398:Signal Transduction; D045868:Sorghum / Q000382:microbiology; D013172:Spores, Fungal; D013559:Symbiosis
chemical_list: D010636:Phenols; D010940:Plant Proteins; D009569:Nitric Oxide; D006861:Hydrogen Peroxide; D019001:Nitric Oxide Synthase; D010650:Phenylalanine Ammonia-Lyase; D020156:Salicylic Acid