title: Hydrogen peroxide induced phenylpropanoids pathway eliciting a defensive response in plants micropropagated in Temporary Immersion Bioreactors (TIBs).
abstract: The relation between the oxidative burst and phenylpropanoid pathways has been studied using the sugarcane cultivar C86-56, which does not release phenolics in agar-base micropropagation systems. In stationary liquid culture, a significant production of phenolic compounds and plant survival were determined in sugarcane plants treated with 5mM H(2)O(2). The spectrophotometer determinations and the gene expression analysis corroborated that releasing of phenolics and soluble θ-quinones was induced during the first 24h of treatment. In comparison with the control treatments, sugarcane plants treated with H(2)O(2) demonstrated differences in the micropropagation-related variables when multiplied in Temporary Immersion Bioreactors (TIBs) supplemented with polyethyleneglycol (PEG 20%). Expression of selected genes related to photosynthesis, ethylene, auxins, oxidative burst, and defense pathways were confirmed during the entire PEG 20% stress in the plants coming from the 5mM H(2)O(2) treatment; whereas, much more heterogeneous expression patterns were evidenced in plants stressed with PEG but not previously treated with H(2)O(2). RT-PCR expression analysis supports the hypothesis that while H(2)O(2) induces the oxidative burst, the phenylpropanoids pathways elicit and maintain the defensive response mechanism in micropropagated sugarcane plants.
authors.affiliation: National Institute for Sugarcane Research, CUJAE Road km 2½, Boyeros 19390, Havana, Cuba. arieldarencibia@gmail.com
authors.forename: Ariel D
authors.initials: AD
authors.lastname: Arencibia
authors.forename: Aydiloide
authors.initials: A
authors.lastname: Bernal
authors.forename: Carlos
authors.initials: C
authors.lastname: Zayas
authors.forename: Elva
authors.initials: E
authors.lastname: Carmona
authors.forename: Cecilia
authors.initials: C
authors.lastname: Cordero
authors.forename: Gloria
authors.initials: G
authors.lastname: González
authors.forename: Rolando
authors.initials: R
authors.lastname: García
authors.forename: Ignacio
authors.initials: I
authors.lastname: Santana
mesh_terms: D019149:Bioreactors; D015870:Gene Expression; D017343:Genes, Plant; D006861:Hydrogen Peroxide / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D009995:Osmosis; D010084:Oxidation-Reduction; D010636:Phenols / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000494:pharmacology*; D016897:Respiratory Burst; D031786:Saccharum / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction; D013312:Stress, Physiological / Q000235:genetics*
chemical_list: D010636:Phenols; D011092:Polyethylene Glycols; D006861:Hydrogen Peroxide