Breeding is more than genetics: a non-genetic toolkit to improve hybrid potato breeding

Summary

For potato, diploid hybrid breeding is a novel technology that has recently been developed. The implementation of this technology in an efficient breeding programme raised new questions. Besides the genetic variation that is present in a breeding programme, breeders have to deal with environmental variation in all stages of the breeding process. Partly, this environmental variation can be used to assess genotypic variation under specific conditions. For another part, variation is a nuisance that needs to be dealt with, to limit its effect on the outcome of variety trials where the goal is to evaluate different genotypes and select for the best inherent performance. In this thesis, we applied environmental variation in breeding trials to enhance the breeding process. Moreover, we determined ways to deal with unwanted variation. We have shown that limiting variation in seedling tuber weight can decrease the variation in yield in cultivar trials. We also developed models that can be used to determine the required plot size for the
required degree of precision.