Breeding value of 2n pollen diploid from hybrids and Phureja in 4x-2x crosses in potatoes

Breeding value of 2n pollen from Phureja — haploid Group Tuberosum diploid hybrids (DHs) and Phureja was compared in crosses with tetraploid cultivars. Mean total yield for Phureja — derived (PT) hybrids significantly exceeded that for DH — derived (DHT) hybrids, and did not differ from that for cultivar parents. PT hybrids had the largest range for total yield, with 13% of the population between 4200 and 5750 gm/plant (0.8 and 4.6% for DHT hybrids and cultivars, respectively). Moreover, the tail of the frequency distribution of total yield for PT hybrids extended 920 gm/plant above that for cultivars. Mean marketable yield for PT hybrids significantly exceeded that for DHT hybrids, but was significantly below that for cultivars. However, the tail of the distribution of marketable yields for PT hybrids exceeded that of the cultivars by 820 gm/plant. Significant general combining ability among 2x and 4x parents for total and marketable yield indicates that the potential of specific crosses can be predicted by average performance of parents in test-crosses. Predictability of parental breeding value and exceptional yield potential of hybrids make 4x-2x breeding an attractive alternative to conventional approaches.