小麦抗腐生型真菌病害的分子机制与广谱抗病育种策略OA

Necrotrophic fungi represent a major class of devastating pathogens threatening wheat production,inducing host cell death to absorb nutrients through the secretion of toxins and cell wall-degrading enzymes.Unlike biotrophic pathogens,the unique"kill-before-feeding"pathogenic strategy of these fungi makes the classic"gene-for-gene"resistance model insufficient to fully elucidate their defense mechanisms.A systematic review of the pathogenic strategies of necrotrophic fungi and wheat defense mechanisms is of significant value for accelerating the genetic improvement of disease resistance in wheat.This article clarifies the pathogenic strategies of necrotrophic or heminecrotrophic pathogens;summarizes a general defense model dominated by cell wall reinforcement,mitogen-activated protein kinase(MAPK)cascades,and jasmonic acid(JA)/ethylene(ET)signaling,as well as specific defense mechanisms primarily involving detoxification by toxin-degrading enzymes,loss-of-function of susceptibility factors,and the alleviation of negative immune regulators.On this basis,a"general-specific"layered synergistic defense model for wheat against necrotrophic fungi is constructed,highlighting the core role of the general defense model in limiting early pathogen colonization and exploring how specific resistance loci enhance basal immunity through signal feedback to form a spatiotemporally integrated defense network.Finally,targeting the pathogenic commonalities of necrotrophic fungi,broad-spectrum disease resistance breeding strategies based on the integration of general defense and specific resistance are proposed,aiming to provide a theoretical basis for breeding new wheat varieties with durable resistance.