Light-dependent oxidative stress determines physiological leaf spot formation in barley.
Light-dependent oxidative stress determines physiological leaf spot formation in barley.
复制标题
光依赖性氧化应激决定大麦生理叶斑的形成。
DOI：
10.1094/phyto.2004.94.6.584
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发表时间：
2004
期刊：
影响因子：
3.2
通讯作者：
A. von Tiedemann
中科院分区：
文献类型：
--
作者：
Yue;A. von Tiedemann
摘要我们以前报道过，在田间条件下，冬、春大麦生理性叶斑病（PLS）的形成依赖于与基因型相关的氧化胁迫。在本研究中，我们寻找因素诱导PLS症状在温室中观察到的领域相似，并调查其关系到活性氧（ROS）代谢。我们发现，在温室中，氧化胁迫诱导春大麦品种。提取物，这是敏感的PLS，以表达症状类似于那些在外地观察到的。受PLS严重影响的叶片表现出显着降低的Halliwell-Asada循环中的关键酶，如抗坏血酸过氧化物酶，谷胱甘肽还原酶，脱氢抗坏血酸还原酶，和单脱氢抗坏血酸还原酶的活性。感病品种的总超氧化物歧化酶（SOD）和Cu/Zn-SOD活性低于不感病品种，而叶绿体特异性Fe-SOD活性高于不感病品种。因此，在叶绿体中不平衡的ROS代谢可能会触发PLS发病率在敏感品种，这是在现场和温室条件下的PLS表达的诱导光是必不可少的事实。因此，在温室条件下，连续光胁迫（7天），而不是光冲击处理，诱导PLS相似的敏感品种田间条件。提取物，但不是在抗性品种。斯嘉丽在蓝色波长光谱（350至560 nm）中具有高比例能量的光比具有明显红色（光合有效辐射）光谱（580至650 nm）的光显著更具有PLS诱导性。暴露于臭氧中不会产生PLS样症状。此外，类似于早期的观察领域，PLS症状的表达与积累的超氧化物（O（2）（-））检测生化和组织化学测定密切相关。综上所述，这些数据表明，PLS在大麦中是基因型依赖的，但它的表达似乎是由某些环境胁迫因子诱导的，其中光合活性辐射起着主要作用。
ABSTRACT We reported previously that physiological leaf spot (PLS) formation in winter and spring barley is dependent on genotype-related oxidative stress under field conditions. In the present study, we searched for factors inducing PLS symptoms in the greenhouse similar to those observed in the field and investigated its relationship to reactive oxygen species (ROS) metabolism. We found that in the greenhouse, oxidative stress induced spring barley cv. Extract, which is sensitive to PLS, to express symptoms similar to those observed in the field. Leaves severely affected by PLS showed significantly lower activities of key enzymes in the Halliwell-Asada cycle such as ascorbate peroxidase, glutathione reductase, dehy-droascorbate reductase, and monodehydroascorbate reductase. The sensitive cultivar also showed lower levels of total superoxide dismutase (SOD) and Cu/Zn-SOD activity but a higher level of chloroplast-specific Fe-SOD activity than that of the insensitive cultivar. Thus, an unbalanced ROS metabolism in chloroplasts may trigger PLS incidence in sensitive cultivars, which is in agreement with the fact that light is essential for the induction of PLS expression under both field and greenhouse conditions. Accordingly, under greenhouse conditions, continuous light stress (7 days), but not light shock treatments, induced PLS similar to that of field conditions in sensitive cv. Extract, but not in resistant cv. Scarlett. Light with a high proportion of energy in the blue wavelength spectrum (350 to 560 nm) was significantly more PLS inductive than light with a pronounced red (photosynthetically active radiation) spectrum (580 to 650 nm). Exposure to ozone did not produce PLS-like symptoms. Furthermore, similar to earlier observations in the field, PLS symptom expression was closely correlated with the accumulation of superoxide (O(2) (-)) detected by both biochemical and histochemical assays. Taken together, these data suggest that PLS in barley is genotype-dependent but its expression appears to be induced by certain environmental stress factors, among which photosyn-thetically active radiation plays a major role.