RESUMO
The genetic nature of polygenic resistance of common wheat to a causative agent of brown rust was studied. It was established, using ditelosomic lines (DT) of the cultivar Chinese Spring, that the majority of examined chromosome arms participate in differential interactions with the pathogen during formation of basic traits of polygenic resistance: the number of pustules (NP) per 1 cm2 of leaf area, the mean spore formation ability of pustule (MSFAP), the mean spore formation ability of fungus per unit of leaf area (MSFAULA). When parameters of spore formation were estimated in the pathogen, it was detected that DT lines 2BL and 5DL did not differentially interact with fungal genotypes carrying different virulence genes. Consequently, minor genes located on 2BS and 5DS arms carry a specific component ofpolygenic resistance. In this model experiment, we confirmed for the first time the hypothesis that polygenic (horizontal) resistance involves two components: a specific component, which is overcome by the pathogen, and a nonspecific component mediating the prolonged resistance.
Assuntos
Ascomicetos/genética , Doenças das Plantas/genética , Folhas de Planta/genética , Locos de Características Quantitativas/genética , Triticum/genética , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Doenças das Plantas/microbiologia , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Triticum/metabolismo , Triticum/microbiologiaRESUMO
Effective, perhaps new genes of resistance to brown rust and powdery mildew expressed in common wheat genome in plant ontogenesis were revealed on additive chromosomes of Aegilops searsii, Aegilops longissima, Secale montanum and Elytrigia elongata.
