EFFECT OF HOST ALLELIC DOSAGE ON TRITICUM-AESTIVUM PUCCINIA-RECONDITASPECIFIC INTERACTION

Allelic dosage changes in host-pathogen interactions (Triticum aestivu m-Puccinia recondita) explain different situations where resistance or susceptibility is observed. Remarkably, the prediction of an interact ion change (from compatible to incompatible) by increasing single host allelic dosage is confirmed. Cases of more lasting resistance could a lso be explained on the basis of these dosage effects. In addition a p arallel between specific and non-specific resistance is established po inting out their basic differences in expression with respect to allel ic dosage effects. These situations, together with new possibilities f or breeding arising from this knowledge, are discussed.