title: Mechanical wounding-induced laticifer differentiation in rubber tree: An indicative role of dehydration, hydrogen peroxide, and jasmonates.
abstract: The secondary laticifer in the secondary phloem of rubber tree are a specific tissue differentiating from vascular cambia. The number of the secondary laticifers is closely related to the rubber productivity of Hevea. Factors involved in the mechanical wounding-induced laticifer differentiation were analyzed by using paraffin section, gas chromatography-mass spectrometry (GC-MS), and Northern-blot techniques. Dehydration of the wounded bark tissues triggered a burst of hydrogen peroxide, abscisic acid, and jasmonates and up-regulated the expression of HbAOSa, which was associated with the secondary laticifer differentiation strictly limited to the wounded area. Application of exogenous hydrogen peroxide, methyl jasmonate, and polyethylene glycol 6000 (PEG6000) could induce the secondary laticifer differentiation, respectively. Moreover, 6-Benzylaminopurine, a synthetic cytokinin, enhanced the methyl jasmonate-induced secondary laticifer differentiation. However, the dehydration-induced secondary laticifer differentiation was inhibited by exogenous abscisic acid. Diphenyleneiodonium chloride (DPI), a specific inhibitor of NADPH oxidase, was effective in inhibiting the accumulation of hydrogen peroxide as well as of jasmonates upon dehydration. It blocked the dehydration-induced but not the methyl jasmonate-induced secondary laticifer differentiation. The results suggested a stress signal pathway mediating the wound-induced secondary laticifer differentiation in rubber tree.
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, 571737, PR China. Electronic address: wmtian@163.com.
authors.forename: Wei-Min
authors.initials: WM
authors.lastname: Tian
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, 571737, PR China.
authors.forename: Shu-Guang
authors.initials: SG
authors.lastname: Yang
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, 571737, PR China.
authors.forename: Min-Jing
authors.initials: MJ
authors.lastname: Shi
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, 571737, PR China.
authors.forename: Shi-Xin
authors.initials: SX
authors.lastname: Zhang
authors.affiliation: Ministry of Agriculture Key Laboratory of Biology and Genetic Resources of Rubber Tree/State Key Laboratory Breeding Base of Cultivation and Physiology for Tropical Crops, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan, 571737, PR China.
authors.forename: Ji-Lin
authors.initials: JL
authors.lastname: Wu
mesh_terms: D000085:Acetates / Q000494:pharmacology; D002454:Cell Differentiation; D003517:Cyclopentanes / Q000494:pharmacology; D008401:Gas Chromatography-Mass Spectrometry; D018506:Gene Expression Regulation, Plant; D028482:Hevea / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D040542:Mechanotransduction, Cellular; D054883:Oxylipins / Q000494:pharmacology; D052585:Phloem / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D011092:Polyethylene Glycols / Q000494:pharmacology; D015398:Signal Transduction; D013312:Stress, Physiological
chemical_list: D000085:Acetates; D003517:Cyclopentanes; D054883:Oxylipins; C000595215:Polyethylene Glycol 6000; D011092:Polyethylene Glycols; C072239:methyl jasmonate; D006861:Hydrogen Peroxide
keywords: Dehydration; Hevea brasiliensis Muell. Arg.; Hydrogen peroxide; Jasmonates; Laticifer differentiation; Vascular cambia