INHERITANCE OF RESISTANCE TO FUSARIUM SPP IN TUBER PROGENIES OF POTATO

Glasshouse-grown seedling tubers of 22 progenies from parents differin g in resistance to Fusarium coeruleum and F. sulphureum (Gibberella cy anogena) were wound-inoculated with a cornmeal + sand culture of one o r other of these dry rot pathogens. With F. coeruleum, differences bet ween progenies were due entirely to differences in the general combini ng abilities (gca) of the parents. Parental and gca values were highly correlated, as were the mean resistance of a progeny and that of its parents. With G. cyanogena the agreement between replicates was poor a nd differences between progenies were less clear. It is suggested that different resistance mechanisms operate against these two pathogens.