中文摘要：

拟南芥IQM2由AT3G13600编码,含有 1 个 IQ基序,是-个钙调素结合蛋白的突变体iqm2 -2及 其野生型Landsberg ereCte（Le〇在丁香假单胞菌番茄致病变种（Pst DC3000）的侵染下,均出现病斑,且程度未呈 现明显差异.光合作用对植物的生长发育和对环境的反应至关重要,荧光参数是衡量光合作用的重要指标.为 此,本研究测定了Pst DC3000侵染下iqm2 -2与 Ler的光系统II叶绿素荧光参数.结果表明,喷菌 7 d 后 Ler和iqm2-2的光量子产量均明显下降,不过 Ler的下降更快且差异显著;光化学猝灭系数和相对电子传递速率也呈 不同程度下降,最大量子产率变化不大.由此推断IQM2参与了植物对病菌的反应,且可能与其对光合作用的影 响有关,但其机制有待研究.

英文摘要：

The Arabidopsis IQM2,coded by AT3G13600,is a calmodulin-binding protein （CaMBP） containingan IQ motif. The leaves of the IQM 2 mutant iqm2-2 and its corresponding wild type Landsberg e re c ta （ h e r ） show the similar lesions after being infected by P s t DC3000. Photosynthesis is essential for plant growth and d e-velopment as well as responding to the environmental cue. Fluorescence parameter is an important indicator to judge photosynthesis. Thus, the fluorescence parameters are measured in iqm2-2 and h e r during infection of P s t DC3000. The resluts show that the quantum yield of h e r and iqm2-2 were significantly decreased after being treated with Ps t DC3000. And the decline rate quantum yield of h e r is more significant than iqm2-2. The photo-chemical quenching value and the electron transport rate also decrease to some extent. However, the maximum quantum yield keeps stable. It can be postulated that IQM2 is involved in the process of plant reaction to dis-ease. However, the mechanism remains to be studied.