棉花响应UV-B辐射的信号初探

以3种棉花为供试材料,研究紫外线-B(UV-B)辐射及外源SNP、ABA叠加处理对棉花幼苗表观形态及内源H2O2与NO水平的影响。结果表明,UV-B辐射引起棉花幼苗叶片呈现锈色伤斑,离体叶片明显失水萎蔫。叶片外源涂抹SNP、ABA能减轻UV-B辐射引起的幼叶伤斑与萎蔫症状,缓解UV-B辐射所造成的伤害。DAB及DAF-2DA染色结果显示,UV-B辐射引起棉花内源H2O2与NO含量增加,而NO的释放通过减少H2O2积累减轻紫外辐射对棉花的伤害。ABA预处理可增强棉花对紫外伤害的耐受能力,且与H2O2与NO的释放密切相关。UV-B辐射对棉花生长造成伤害,H2O2、NO及ABA都参与棉花应答UV-B胁迫的信号转导过程。

Research on the Signals of Cotton in Response to UV-B Radiation

Phenotype and hydrogen peroxide and nitric oxide were studied in three kinds of cotton under ultraviolet-B(UV-B) radiation with or without SNP and ABA treatment.The results indicated that leaves of cotton seedlings showed obvious rust,and leaves in vitro dehydrate apparently suffering UV-B stress.Pretreatment with sudium nitroprusside(SNP) and abscisic acid(ABA) lightened rust and wilt symptom of the leaves due to UV-B radiation.Both hydrogen peroxide(H2O2) dyed with 3,3-diaminobenzidine(DAB) and nitric oxide(NO) labelled by 4,5-diaminofluorescein diacetate(DAF-2DA) were increased after UV-B radiation than untreated control.And the release of NO alleviated the damage from UV-B radiation by reducing the accumulation of H2O2.In additon,pretreatment with ABA significantly increased the tolerance of cotton,which is bound up with the production of H2O2 and NO.Therefore,UV-B radiation caused damage of cotton during the growth and development,and all of H2O2,NO and ABA are members of the signal transduction during the interaction between cotton and UV-B stress.