Metabolic changes in rice seedlings with different submergence tolerance after desubmergence
Metabolic changes in rice seedlings with different submergence tolerance after desubmergence
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DOI：
10.1016/s0098-8472(01)00126-5
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发表时间：
2002-05-01
影响因子：
5.7
通讯作者：
Tanaka, K
中科院分区：
文献类型：
--
作者：
Kawano, N;Ella, E;Tanaka, K
当不耐山洪的水稻品种被淹没时，它们比耐山洪品种表现出更大的形态变化，例如伸长和失绿。这些形态反应是由淹没过程中产生的乙烯引起的，然而，不耐受品种的可见损伤是在脱离淹没后而不是淹没过程中明显发生的，这可能是由于氧化损伤。我们研究了浸没过程中产生的乙烯对抗氧化剂含量和浸没后氧化损伤的影响。当水稻 (Oryza sativa) 浸水 8 天时，耐性品种 (BKNFR) 和不耐性品种 (Mashuri 和 IR42) 在浸水过程中抗坏血酸浓度均下降。沉水3天后，耐性品种的总抗坏血酸和抗坏血酸恢复较快，而不耐性品种则恢复缓慢，丙二醛生成量增加，且成活率较低（约30%）。然而，对不耐受的品种施用200mg·l(-1)的AgNO3作为乙烯拮抗剂，抑制了沉水后抗坏血酸的减少和丙二醛形成的增加，并将成活率提高至约60%。通过在光照下孵育 24 小时，从浸没的 IR42 向叶盘供应抗坏血酸抑制了丙二醛形成的增加。此外，丙二醛形成与抗坏血酸浓度（r = - 0.93）和存活百分比（r = -0.98）之间观察到强烈的负相关性。我们的研究结果表明，淹水过程中积累的乙烯对不耐水稻品种淹水后的抗氧化机制产生不利影响，而抗坏血酸是淹水稻苗恢复的体内重要抗氧化剂。 (C) 2002 Elsevier Science B.V. 保留所有权利。
When flash flood intolerant rice cultivars are submerged, they show greater morphological changes such as elongation and chlorosis than tolerant cultivars. These morphological responses are caused by ethylene produced during submergence, however, a visible damage of intolerant cultivars is markedly developing after desubmergence rather than during submergence, which is probably due to oxidative damage. We studied the effect of ethylene produced during submergence on antioxidant content and oxidative damage after desubmergence. When rice (Oryza sativa) was submerged for 8 days, both tolerant cultivar (BKNFR) and intolerant cultivars (Mashuri and IR42) showed a decrease in ascorbate concentration during submergence. After 3 days of desubmergence, the tolerant cultivar showed a rapid recovery of total ascorbate and ascorbic acid, whereas intolerant cultivars showed a slow recovery of them, an increase in malondialdehyde formation, and low survival rate (about 30%). However, applying 200 mg l(-1) of AgNO3 as an ethylene antagonist to intolerant cultivars suppressed the decrease in ascorbate and the increase in malondialdehyde formation after desubmergence, and improved survival rate to about 60%. Ascorbic acid supply to leaf discs from submerged IR42 suppressed increase in malondialdehyde formation by incubation under the light for 24 h. In addition, strong negative correlations were observed between malondialdehyde formation with ascorbate concentration (r = - 0.93) and with percentage of survival (r = -0.98). Our results indicate that the accumulated ethylene during submergence adversely affected antioxidant mechanism in intolerant rice cultivars after desubmergence, and ascorbic acid was an important antioxidant in vivo for the recovery of submerged rice seedlings. (C) 2002 Elsevier Science B.V. All rights reserved.