WHEAT POWDERY MILDEW PSEUDORESISTANCE PRODUCED BY BLUMERIA GRAMINIS F. SP. TRITICI THROUGH PREEXISTENT AND POSTINFECTION STRUCTURAL MECHANISM PUBLISHEDGheorghe Popescu, Otilia Cotuna, Floarea Adam None
Biotrophic fungus Blumeria graminis in wheat can produce quantitative and qualitative loses. In these condition prevention and control of this parasite fungus can be realised through the application of the modern concept of plant protection “Integrated plant protection”. This complex system provides constant qualitative and quantitative yields, and the non pollutant subsystem that is also economically is “genetic control”, respectively the genetic resistance of the wheat plants. Wheat varieties are avoiding the incidence of powdery mildew, or are diminishing the fungus aggressiveness and virulence through structural and genetic mechanisms. Structural mechanisms are imprinting a false resistance of a pseudoresistance, or non-specific that is provided by the presence in wheat varieties by pre-existent structures as is the cuticula, epidermal cells membrane and his impregnation of it with different organic substances, ectoderm and pilosity and “de novo” postinfectional structures as are apresoria – MA and haustorial MAT-EH. In fact the glycoproteins are produced by the wheat varieties genes. These structures are determined by pseudoresistance being in fact the defending responses of the wheat varieties (Dor, Falnic, Gruia, Gloria and Bercsy studied during 2003-2005) to the action of evolutionary and conservative genome of the fungus – PAMPs, and also by the activity of resistance genes Pm (powdery mildew).
powdery mildew; wheat; pseudoresistance; genes; preexistent and postinfection structures