GENETIC ANALYSIS OF RESISTANCE TO PUCCINIA STRIIFORMIS IN THE WHEAT DIFFERENTIAL CULTIVARS HEINES VII, HEINES PEKO AND STRUBES DICKKOPF

摘要

One major gene for resistance to isolate WYR 85-22 of race 6EO of Puccinia struformis was identified by genetic analysis of the differential cultivars Heines Peko, Strubes Dickkopf and Heines VII. This gene was different from Yr2 and Yr6 already identified in Heines Peko (Yr2, Yr6) and Heines VII (Yr2), was allelic in the three cultivars and also to a gene expressed in the other differentials Reichersberg 42 (Yr7) and Clement (Yr9). In Heines Peko, Strubes Dickkopf and Heines VII, a minor gene was also postulated, which, it is proposed, gave only a low level of resistance by itself but strengthened the expression of the major gene when the latter was homozygous or heterozygous. The genetics of the resistance was analysed using six resistance classes and applying multidimensional analyses. The number of resistance genes was hypothesized using data from F3 families from crosses between the three differentials and the cultivar Heines Kolben, which is susceptible to this race.