玉米木栓质抵抗禾谷镰刀菌侵染的生理机制

Physiological Mechanism of Resistance of Maize Suberin against Fusarium graminearum Infection

木栓质是植物体内的一种以甘油酯-酚类为基本单元的生物聚酯。木栓质作为一种保护性屏障,能有效抵御病原菌的入侵。相较于一般植物的单木栓质层,玉米的双木栓质结构对于抵御外界病原菌入侵的作用尚不明确。研究建立玉米—禾谷镰孢互作体系,在此基础上进行玉米根部木栓质差异响应禾谷镰孢侵染的基因型筛选,进而进行玉米根部的组织观察及不同基因型玉米根部的禾谷镰孢定量分析。结果表明,禾谷镰孢对不同基因型玉米的根部木栓质差异与禾谷镰孢的侵染水平呈反比。玉米根部木栓质含量越高,抑制禾谷镰孢侵染的能力越强。研究表明玉米根部的双木栓质结构具备有效抵抗外界病原入侵的能力。

Suberin is a kind of biological polyester in plants with glycerides-phenols as the basic unit.It serves as a protective barrier against the invasion of pathogenic fungi.Unlike the single-layered suberin of general plants,the influence of the double-suberin structure of maize on the invasion of external pathogens is still unclear.In this study,a maize F.graminearum interaction system was established,and on this basis,the genotype screening of the difference in suberin in maize roots in response to F.graminearum infection was carried out.Then the tissue obser⁃vation of maize roots and the quantitative analysis of F.graminearum biomass in different genotypes of maize roots were carried out to compare the infectivity differences of F.graminearum on different genotypes of maize.The re⁃sults indicated that the infection level of F.graminearum on different genotypes of maize was inversely proportional to the suberin contents in the root.The higher the suberin content in the maize roots,the stronger the ability to inhib⁃it F.graminearum infection.This study suggests that the dual suberin layers in the maize roots can effectively de⁃fense against the invasion of pathogens.