Oxidative damage in pea plants exposed to water deficit or paraquat
Oxidative damage in pea plants exposed to water deficit or paraquat
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DOI：
10.1104/pp.116.1.173
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发表时间：
1998-01-01
期刊：
影响因子：
7.4
通讯作者：
Becana, M
中科院分区：
文献类型：
--
作者：
Iturbe-Ormaetxe, I;Escuredo, PR;Becana, M
中度水分亏缺(水势为-1.3 Mpa)对豌豆(Pisum Sativum L.cv Lin)叶片的光合作用有75%的抑制作用，玉米黄质、丙二醛、氧化蛋白、线粒体、细胞质和叶绿体超氧化物歧化酶活性增加。严重的水分亏缺(-1.9 Mpa)几乎完全抑制了光合作用，降低了叶绿素、β-胡萝卜素、新黄质和叶黄素，并导致紫黄质进一步转化为玉米黄质，这表明光合作用器官受到了损害。抗氧化剂和吡啶核苷酸持续减少，催化铁、丙二醛和氧化蛋白质积累。百草枯(PQ)处理导致光合作用、水分含量、蛋白质和大多数抗氧化剂的显著下降，并诱导玉米黄质和受损蛋白质的积累。PQ显著降低抗坏血酸、NADPH、抗坏血酸过氧化物酶和叶绿体Fe-超氧化物歧化酶活性，使氧化谷胱甘肽、NAD(+)、NADH和催化铁显著升高。结果表明，林肯叶片中催化铁含量的增加和抗氧化保护作用的降低可能与严重水分亏缺和PQ引起的氧化损伤有关，但与中度水分亏缺引起的初期胁迫无关。研究结果还表明，豆科牧草品种对水分胁迫氧化损伤的耐受性在很大程度上取决于品种。
The application of a moderate water deficit (water potential of -1.3 MPa) to pea (Pisum sativum L. cv Lincoln) leaves led to a 75% inhibition of photosynthesis and to increases in zeaxanthin, malondialdehyde, oxidized proteins, and mitochondrial, cytosolic, and chloroplastic superoxide dismutase activities. Severe water deficit (-1.9 MPa) almost completely inhibited photosynthesis, decreased chlorophylls, beta-carotene, neoxanthin, and lutein, and caused further conversion of violaxanthin to zeaxanthin, suggesting damage to the photosynthetic apparatus. There were consistent decreases in antioxidants and pyridine nucleotides, and accumulation of catalytic Fe, malondialdehyde, and oxidized proteins. Paraquat (PQ) treatment led to similar major decreases in photosynthesis, water content, proteins, and most antioxidants, and induced the accumulation of zeaxanthin and damaged proteins. PQ decreased markedly ascorbate, NADPH, ascorbate peroxidase, and chloroplastic Fe-superoxide dismutase activity, and caused major increases in oxidized glutathione, NAD(+), NADH, and catalytic Fe. It is concluded that, in cv Lincoln, the increase in catalytic Fe and the lowering of antioxidant protection may be involved in the oxidative damage caused by severe water deficit and PQ, but not necessarily in the incipient stress induced by moderate water deficit. Results also indicate that the tolerance to water deficit in terms of oxidative damage largely depends on the legume cultivar.