中文摘要：

许多真菌的植物病菌能分泌草酸酸(OA ) ，它是关键病原的决定因素并且在感染过程期间在病原体的致病力和毒力起重要作用。然而，植物怎么对 OA 应力作出回应，仍然需要进一步的描述。在这研究，我们观察了 Arabidopsis thaliana 的生理、分子的回答到 OA 应力。6-wk-old A 的叶子。 thaliana 与 OA 被喷洒并且分别地提取了水，并且 0 ， 2 ， 4 ， 8 ， 12 ，和 24 h 以后，叶子被收集并且 MDA ， H2O2 ，和 GSH 的内容，和猫的活动，草皮，并且邮政部门被决定， PR1 和 PDF1.2 的表情也被学习。在 30 mmol L 的压力下面 ? 1 OA，草皮活动首先被提高减少 O2 的累积 ? 。但是立即，邮政部门，猫，和 GSH 都极其减少了导致 H2O2，和 MDA 内容的累积以后增加了 24 h。在 OA 使用了以后， GSH 活动在 24 h 显著地被提高。然而， H2O2 同时消除了，建议邮政部门和猫力量的活动抑制是在 OA 下面引起了 Arabidopsis 房间的缺陷的原因强调。RT-PCR 结果显示了那 PDF1.2，发信号的 JA/ET 的标记基因显著地被导致；PR1，在 SA 发信号的指示物基因， slighlty 在 OA 应力以后从 8 ～ 12 h 被导致。在结论， Arabidopsis 可以招募反应的氧的新陈代谢，表明小径对 OA 作出回应的 JA/ET 和 SA 强调。这些结果将便于我们进一步理解对 OA 和 OA 依赖的真菌的感染的植物反应的机制。

英文摘要：

Many fungal phytopathogens can secrete oxalic acid （OA）, which is the crucial pathogenic determinant and plays important roles in pathogenicity and virulence of pathogen during infection process. However, how plants respond to OA stress still needs further characterization. In this study, we observed the physiological and molecular responses of Arabidopsis thaliana to OA stress. The leaves of 6-wk-old A. thaliana were sprayed with OA and distilled water respectively, and 0, 2, 4, 8, 12, and 24 h later, the leaves were collected and the contents of MDA, H2O2, and GSH, and the activities of CAT, SOD, and POD were determined and the expressions of PR1 and PDF1.2 were also studied. Under the stress of 30 mmol L-1 OA, SOD activity was first enhanced to reduce the accumulation of O2.-. But immediately, POD, CAT, and GSH all decreased extremely resulting in the accumulation of H2O2, and the MDA content increased 24 h later. GSH activity was enhanced significantly at 24 h after OA used. However, H2O2 wasn＇t eliminated at the same time, suggesting that the activity inhibitions of POD and CAT might be the reasons that caused Arabidopsis cells＇ impairment under OA stress. RT-PCR results indicated that PDF1.2, a marker gene of the JA/ET signaling was significantly induced; PR1, an indicator gene in SA signaling, was slighlty induced from 8 to 12 h after OA stress. In conclusion, Arabidopsis may recruit metabolism of reactive oxygen, both JA/ET and SA signaling pathways to respond to OA stress. These results will facilitate our further understanding the mechanisms of plant response to OA and OA-dependent fungal infection.