【作者】 傅泓； 安建宇； 林程； 胡伟民； 胡晋； 关亚静；

【Author】 FU Hong;AN Jian-Yu;LIN Cheng;HU Wei-Min;HU Jin;GUAN Ya-Jing;Seed Science Center,Institute of Crops Science,College of Agriculture and Biotechnology,Zhejiang University;

【机构】 浙江大学农业与生物技术学院作物科学研究所种子科学中心；

【摘要】 以自然老化和人工老化的株两优06（ZLY06）和春优84（CY84）种子为材料,用不同活性氧（过氧化氢、Fenton和甲基紫精）溶液引发处理,发现相对于其他两种处理,Fenton引发可显著提高老化种子的活力,效果最佳。Fenton引发一方面促进老化种子吸胀过程中的α-淀粉酶活性,促进赤霉素（GA₃）合成与脱落酸（ABA）分解相关基因表达,提高GA₃含量,显著降低ABA含量及ABA/GA₃比值,促进种子萌发。另一方面,Fenton引发提高水稻幼苗过氧化物酶（POD）和超氧化歧化酶（SOD）活性,降低幼苗中过氧化氢的含量,大幅增加叶片叶绿素含量,促进幼苗生长。且Fenton引发对自然老化和人工老化种子有类似的促进效果。此外,研究表明,人工老化与自然老化后的种子在发芽结果上能够较好地吻合,但自然老化后的水稻种子旺-淀粉酶活性、幼苗POD和SOD活性显著低于人工老化。在在分子水平上,人工老化是通过抑制GA合成和ABA分解相关基因,同时促进GA分解和ABA合成相关基因,抑制种子萌发;而自然老化后种子中GA或ABA的合成和分解基因的表达同时提高或下降。由此表明,自然老化和人工老化的确存在一些本质上的不同。更多还原

【Abstract】 Natural and artificial aged seeds,from rice varieties Zhuliangyou 06（ZLY06） and Chunyou 84（CY84）,were primed with three reactive oxygen species（H₂ O₂,Fenton and methyl viologen）.The results showed that Fenton priming had the best effect to significantly improve the vigor of aged seeds as compared with H₂ O₂ and methyl viologen.On the one hand,Fenton triggered the promotion of a-amylase activity during imbibition of aged seeds,promoted the gibberellin（GA₃）synthesis and abscisic acid（ABA） decomposition related genes expressions,enhanced GA₃ content,significantly reduced ABA content and the ratio of ABA/GA₃,and accelerated seed germination.On the other hand,Fenton priming increased the peroxidase（POD） andsuperoxide dismutase（SOD）activitiesin rice seedling,decreased the hydrogen peroxide content,improvedobviously the chlorophyll content and promoted the seedling growth.Fenton priming had a similar promotion effect on natural and artificial aged seeds.In addition,the results showed that the germination of artificial aged seeds was consistent with that of natural aged ones,but the a-amylase in seed,POD and SOD activitiesin seedling treated by natural agingwere significantly lower than those treated by artificial aging.At the molecular level,artificial aging inhibited seed germination through suppression of GA synthesis and ABA decompositionrelated genes expressions and promotion of GA decomposition and ABA synthesis related genes expressions;while in the natural aged seeds,the expressions of GA or ABA synthesis and decomposition genes wereusually raised or decreased simultaneously.It suggested that there were some essential differences between natural aging and artificial aging.更多还原