國立臺灣大學農藝學系暨研究所高景輝2006-07-262018-07-112006-07-262018-07-112005-07-31http://ntur.lib.ntu.edu.tw//handle/246246/19849本研究主要探討脫落酸（ABA）所誘導的水 稻切離葉片老化是否經由H2O2 所啟動。 ABA 導致水稻切離葉片H2O2 含量增加，此 H2O2 含量之增加早於ABA 所引起之葉片老 化。H2O2 捕捉劑dimethylthiourea（DMTU） 可有效的抑制ABA 所引起之葉片老化， malondialdehyde (MDA) 含量之增加，抗氧 化酵素（ superoxide dismutase, ascorbate peroxidase, glutathione redutase 與catalase） 活性之增加。Diphenyleneiodonium chloride (DPI) 與imidazole (IMD) [NADPH oxidase 之抑制劑] 以及KCN 與NaN3 [peroxidase 之抑制劑] 亦可阻止ABA 所誘導H2O2 之含 量增加，顯示NADPH oxidase 與peroxidase 是負責ABA 引起形成H2O2 之主要酵素。 DPI、IMD、KCN 與NaN3 亦可抑制ABA 所 加速之葉片老化，MDA 含量之增加，抗氧 化酵素活性之增加以及抗氧化物含量之降 低。這些結果說明，H2O2 可做為ABA 所誘 導水稻葉片老化之訊息分子。The role of H2O2 in abscisic acid (ABA)- induced rice leaf senescence is investigated. ABA treatment resulted in H2O2 production in rice leaves, which preceded the occurrence of leaf senescence. Dimethylthiourea, a chemical trap for H2O2, was observed to be effective in inhibiting ABA-induced senescence, ABAinduced malondialdehyde (MDA) content, ABA-induced antioxidantive enzyme activities (superoxide dismutase, ascorbate peroxidase, glutathione reductase and catalase), and ABA-induced antioxidant content (ascorbic acid and reduced glutathione) in rice leaves. Diphenyleneiodonium chloride (DPI) and imidazole (IMD) [inhibitors of NADPH oxidase], and KCN and NaN3 [inhibitors of peroxidase] prevented ABApromoted senescence, ABA-increased MDA contents, ABA-increased antioxidative enzyme activities, and ABA-decreased antioxidant contents in rice leaves. These results suggest that H2O2 is involved in ABA-induced senescence of rice leaves.application/pdf393500 bytesapplication/pdfzh-TW國立臺灣大學農藝學系暨研究所脫落酸過氧化氫葉片老化水 稻Abscisic acidHydrogen peroxideLeaf senescenceRicereporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/19849/1/932313B002062.pdf