Evaluation of yield and quality traits in Russet-Chipper and 4x-2x crosses in potato (Solanum tuberosum L.)

Genetic improvement of yield in potato has lagged behind that of other major crops over the past century, prompting the search for alternative breeding methods that may accelerate the development of improved cultivars. One proposed strategy has been to identify and use heterotic groups to increase the yield and consistency of clones produced by breeding programs. To investigate this approach, hybridizations were made between “Russet” and “Chipper” class elite long-day adapted potato clones, as well as between elite long-day adapted tetraploid clones and clones from an improved diploid population derived from Group Phureja and Group Stenotomum (4x-2x crosses). Field evaluation of random progeny derived from Russet-Chipper crosses had few notable benefits when compared to clones derived from crosses made within the Russet and Chipper groups. However, many of the clones derived from 4x-2x crosses out-yielded the highest yielding clones from crosses between elite long-day adapted tetraploid potato clones in initial evaluations. While every favorable quality trait measured was present in at least several clones derived from 4x-2x crosses, the frequency of many of these favorable quality traits was lower than in crosses between elite long-day adapted tetraploid potato clones. Our results suggest that Russet-Chipper crosses could be used to develop improved Chipper-type cultivars. However, continued selection of parental clones in 4x and 2x populations would likely be required before a high yielding clone with superior quality characteristics could be expected from these 4x-2x crosses.