R‐41, a sunflower restorer inbred line, carrying two genes for resistance against a highly virulent Spanish population of Orobanche cernua

The inheritance of resistance to a highly virulent population of sunflower broomrape (Orobanche cernua) has been studied in R‐41, a Spanish sunflower restorer inbred line. Using the cytoplasmic male‐sterile inbred line HA‐89 (cms; very susceptible to this population of broomrape) as a female parent, progenies of the cross with R‐41, i.e. Fl, F2 and BC1 to both parents, as well as the parental lines, were analysed for their reaction to the broomrape population EC‐94. The goodness of fit of the observed vs expected segregation ratios indicated that the inheritance of resistance to broomrape in line R‐41 is conferred by two independent dominant genes.