Role of reactive oxygen species in the response of barley to necrotrophic pathogens
Role of reactive oxygen species in the response of barley to necrotrophic pathogens
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DOI：
10.1007/s00709-002-0064-1
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发表时间：
2003-01-01
期刊：
影响因子：
2.9
通讯作者：
Able, AJ
中科院分区：
文献类型：
--
作者：
Able, AJ
在离体叶系统中研究了大麦（Hordeum vulgare）和两种真菌坏死营养菌（Rhynchosporium secalis 和 Pyrenophora teres（大麦叶烫伤和网斑病的致病因子））之间的相互作用。在对黑根霉的敏感和抗性反应中都观察到了表皮细胞特异性的早期氧化爆发。随后，观察到第二次易感人群特异性爆发。第一次和第二次爆发的时间点分别与病原体接触质膜和随后的细胞死亡密切相关。相比之下，对圆叶轮菌的抗性和敏感反应中的HO2./O-2(-)水平有限。在后期阶段，仅在紧邻酚类褐变和敏感反应期间观察到的细胞死亡的2至3个表皮细胞中检测到HO2./O-2(-)。然而，在与所观察到的由圆叶轮虫引起的病变相邻的大多数叶肉细胞中检测到了 H2O2。与用 R. secalis 攻击期间的观察结果相反。在活性氧产生部位，P teres 和质膜之间没有明显的直接接触。在用任一病原体攻击之前用抗氧化剂预渗透叶子对抗性反应没有影响，但确实限制了病原体的生长并抑制了易感反应期间细胞死亡的程度。这些结果表明，在用坏死营养真菌叶病原体攻击易感植物细胞期间，活性氧在诱导细胞死亡中可能发挥作用。
The interactions between Hordeum vulgare (barley) and two fungal necrotrophs, Rhynchosporium secalis and Pyrenophora teres (causal agents of barley leaf scald and net blotch), were investigated in a detached-leaf system. An early oxidative burst specific to epidermal cells was observed in both the susceptible and resistant responses to R. secalis. and later on, a second susceptible-specific burst was observed. Time points of the first and the second burst correlated closely with pathogen contact to the plasma membrane and subsequent cell death, respectively. HO2./O-2(-) levels in resistant and susceptible responses to P. teres were limited in comparison. During later stages, HO2./O-2(-) was only detected in 2 to 3 epidermal cells immediately adjacent to phenolic browning and cell death observed during the susceptible response. However, H2O2 was detected in the majority of mesophyll cells adjacent to the observed lesion caused by P teres. In contrast to observations during challenge with R. secalis. no direct contact between P teres and the plasma membrane at sites of reactive oxygen species production was evident. Preinfiltration of leaves with antioxidants prior to challenge with either pathogen had no effect on resistance responses but did limit the growth of the pathogens and inhibit the extent of cell death during susceptible responses. These results suggest a possible role for reactive oxygen species in the induction of cell death during the challenge of a susceptible plant cell with a necrotrophic fungal leaf pathogen.