钙与叶锈菌侵染诱导小麦防卫反应的关系

采用活体注射法将不同浓度的钙信使阻断及激活药物注入小麦叶片,其中阻断药物注射后立即接种叶锈菌,研究了钙信使与小麦受叶锈菌侵染诱导的防卫反应的关系。结果表明,用Ca2 螯合剂EGTA除去或降低胞外Ca2 浓度,用Ca2 通道阻断剂Verapamil或La3 阻断胞外Ca2 进入胞质,都能部分地抑制叶锈菌诱导的防卫反应,即PAL,POD的活性升高和过敏性反应(HR)的发生。抑制程度随药物浓度升高而增高。注射Ca2 载体A23187能部分模拟叶锈菌侵染诱导的这3种防卫反应。说明叶锈菌侵染诱导的PAL,POD活性升高和HR的发生,需要胞外Ca2 进入胞内,Ca2 参与了叶锈菌侵染激活防卫反应的信号转导过程。

The Effects of Ca2+ on the Induction of Defence Responses by Wheat Leaf Rusts

Ca(2 )chelator(EGTA),Ca(2 ) channel blocker(La(3 )or verapmil) and Ca(2 ) ionophore A23187 were separately injected into the primary seedling leaves of wheat(Triticum aestivum cv.Lovrin 10) immediately before the leaves were inoculated with an incompatible race 366 of leaf rust(Puccinia recondite f.sp.tritici) in order to study their effects on the activities of PAL, POD and HR,which are important defense responses of host cells in the interaction of wheat-leaf rust.The results showed that the calcium inhibition reagents could partly inhibite the three defense responses.The higher the concentration,the stronger the inhibition.The Ca(2 ) ionophore A23187 could induce the three defense responses as leaf rusts.These suggested that the influx of extracellular Ca(2 )is essential conditions for the induction of defense response by leaf rust infection.In other words,Ca(2 )may be involved in the signal transduction of the induction of defense response by leaf rust fungus.This thesis supplied the pharmic evidences.