植物数量抗病基因克隆及其抗性机理的研究进展

培育广谱、持久抗病的作物品种，不仅需要深入研究质量抗病性，而且需要更深入地洞悉数量抗病性的可能作用机理。而目前，人们对数量抗病基因的可能特征和数量抗病性的机理的认识还相当模糊，这在很大程度上限制了数量抗病基因在育种实践中的应用。本文首先综述数量性状座位（quantitative trait loci，QTL）的克隆策略和精确获取数量抗病性状值的方法；其次根据数量抗性座位（quantitative resistance loci。QRL）的相关研究进展，对QRL的可能特征进行一定的综述，认为部分QRL的抗性机理直接对应于R基因、抗病基因类似物（resistance geneanalogs，RGA）、防卫基因、防卫反应途径中的相关基因等在植物抗病性上的作用机理；最后，作者推测存在4种抗性特征的QRL，即小种特异性或非特异性QRL和“病原菌”特异性或广谱性QRL，并认为数量抗性持久性的遗传基础与这些不同特征的QRL间有着密切的联系。该综述将对QRL的候选基因分析和克隆、数量抗病机理研究和QRL的育种应用提供有益的参考。

Progress on Cloning of Quantitative Disease Resistance Gene in Plant and Studying its Possible Resistance Mechanism

In order to breed cultivars with broad-spectrum and durable disease resistance, we should know the mechanism of qualitative resistance as well as quantitative resistance. However, it is still a challenge for us to understand the character of quantitative resistance gene and the mechanism of quantitative disease resistance, which limits the practical breeding use of quantitative resistance gene to a great extent. In the present paper, we firstly discussed the strategy in cloning quantitative trait locus (QTL) and the method to acquire accurate phenotype value for identifying quantitative resistance locus (QRL); secondly, we discussed that the mechanisms of some QRL are corresponded to that of R-gene, resistance gene analogs (RGA), defense gene and the genes involved in defense response pathways in plant, respectively; thirdly, we addressed that the QRL could be classified into four types based on their resistance characters, race specific, race non-specific, pathogen specific and broad spectrum; and we thought that the genetic basis of durable quantitative disease resistance is closely connected with these different types of QRL. All these discussions would not only be helpful in cloning and breeding use of QRL, but also provide insights into the mechanism of quantitative disease resistance.