Photosynthetic characteristics and protective mechanisms against oxidative stress during chilling and subsequent recovery in two maize varieties differing in chilling sensitivity
Photosynthetic characteristics and protective mechanisms against oxidative stress during chilling and subsequent recovery in two maize varieties differing in chilling sensitivity
复制标题
DOI：
10.1016/s0168-9452(01)00460-5
复制
发表时间：
2001-09-01
期刊：
影响因子：
5.2
通讯作者：
Sánchez-Diaz, M
中科院分区：
文献类型：
--
作者：
Aroca, R;Irigoyen, JJ;Sánchez-Diaz, M
对两个不同冷敏感性的玉米品种（Z7，耐受性和Penjalinan，敏感性）的植株进行5天的5 ℃、300 μ mol m（-2）s（-1）PPFD和12小时光周期处理，并在相同的光照条件下于25 ℃恢复3天。气体交换和叶绿素荧光分析表明，两个品种在低温期的光抑制程度相同。而叶绿素荧光分析表明，能量耗散过程中增加，主要是在Z7叶片。此外，Z7叶片表现出更高的类胡萝卜素/总叶绿素比Penjalinan，另一方面，Z7叶片表现出显着增加的抗氧化酶活性（超氧化物歧化酶，SOD，抗坏血酸过氧化物酶，APX，谷胱甘肽还原酶，GR），而Penjalinan降低细胞质和叶绿体CuZn和Fe SOD活性和增加APX和GR活性在较小程度上比Z7。这种抗氧化酶的行为可能是负责超氧阴离子（O-2（-））在Penjalinan低温期间造成的叶绿体损伤。当植物恢复到25 ℃时，Z7叶片迅速恢复光合活性，从而降低了活性氧产生的潜在能力。相反，Penjalinan叶片在25 ℃下3天后才恢复光合活性。冷恢复过程中，Penjalinan叶片SOD和GR活性升高，APX活性降低。因此，由于H2 O2积累的氧化损伤可能发生在Penjalinan叶片。(C)2001爱思唯尔科学爱尔兰有限公司保留所有权利。
Plants of two maize varieties differing in chilling sensitivity (Z7, tolerant and Penjalinan, sensitive) were subjected to 5 degreesC, 300 mu mol m(-2) s(-1) PPFD and 12-h photoperiod during 5 days and recovered during 3 days at 25 degreesC at the same light regime. Gas exchange and chlorophyll fluorescence analyses showed the same degree of photoinhibition during chilling period in both varieties. However, chlorophyll fluorescence analysis showed an increase in the process of energy dissipation mainly in Z7 leaves. Besides, Z7 leaves showed higher carotenoids/total chlorophyll ratio than Penjalinan, On the other hand, Z7 leaves showed a marked increase in antioxidant enzyme activities (superoxide dismutase, SOD; ascorbate peroxidase, APX; glutathione reductase, GR), while in Penjalinan decreased the cytoplasmatic and chloroplastic CuZn and Fe SODs activities and increased the APX and GR activities in less extent than in Z7. Such antioxidant enzyme behaviour could be responsible for chloroplast damage caused by superoxide anion (O-2(-)) during chilling in Penjalinan. When plants were returned to 25 degreesC, Z7 leaves quickly recovered photosynthetic activity thus diminishing the potential power for reactive oxygen species generation. On the contrary, Penjalinan leaves only recovered photosynthetic activity after 3 days at 25 degreesC. Moreover, during chilling recovery, Penjalinan leaves increased SOD and GR activity, while APX activity decreased. As a consequence, oxidation damage due to H2O2 accumulation could occur in Penjalinan leaves. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.