Inheritance of resistance to Puccinia coronata var. avenae in six selections of Avena sterilis

Summary Six selections of Avena sterilis, introduced from Israel as sources of resistance to oat crown rust, were crossed with susceptible A. byzantina Frazier. The number of genes conditioning resistance to culture H-14 of race 326 of Puccinia coronata var. avenae in each of the six selections was determined from studies of F₁, F₂ and F₃ populations from the crosses. P.I. 287211, P.I. 295919 and P.I. 296244 each appeared to have a single dominant gene for resistance, and P.I. 296265 and P.I. 296266 each two dominant ones. C.I. 8295 had a single partially dominant gene for resistance. Crosses among the A. sterilis parents indicated that at least four different genes conditioned resistance to culture H-14.Association between F₂ reaction to crown rust and morphological characters of the spikelet was determined with the % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGak0dh9WrFfpC0xh9vqqj-hEeeu0xXdbba9frFj0-OqFf% ea0dXdd9vqaq-JfrVkFHe9pgea0dXdar-Jb9hs0dXdbPYxe9vr0-vr% 0-vqpWqaaeaabaGaaiaacaqabeaadaqaaqaaaOqaaiabeE8aJnaaCa% aaleqabaGaaGOmaaaaaaa!39FC!\\chi ^2 \] test for independence. In four crosses, all spikelet characters appeared to be independent of rust reaction. In Frazier x P.I. 296244, basal pubescence of the lemma on the secondary floret appeared to be associated with reaction to crown rust. Strong association between reaction to crown rust and lemma pubescence on the primary floret was evident in Frazier x P.I. 296265.