A NEW SOLANUM FENDLERI MUTANT LACKING PURPLE PIGMENT

Authors: FERNANDEZ, C - UNIV OF WI MADISON; Bamberg, John

Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2004
Publication Date: 8/10/2004
Citation: Fernandez, C.J., Bamberg, J.B. 2005. A new Solanum fendleri mutant lacking purple pigment. American Journal of Potato Research. 82:69

Interpretive Summary:

Technical Abstract: A sample of S. fendleri (PI 620874) was collected by the authors from a previously unreported site in the mountains of southern Arizona in September 2001. When the original seed was grown at the Genebank, two of 25 seedlings produced white flowers, and upon closer inspection were found to be completely devoid of the purple pigmentation on the tubers, stems and underside of leaves characteristic of this species. Ploidy, crossability and all other aspects of plant appearance confirmed these to be true S. fendleri mutants, not mislabeled seedlings of another species. S. fendleri, like other species of Ser. Longipedicellata (LON) are disomic tetraploids, so a recessive mutant at the P locus would presumably make the genotype of these mutants pp pp, that is, 'P-less'. Crossing studies showed that P-less plants always breed true. F1 hybrids with normal (purple) plants from many populations encompassing all LON species produced only one P-less seedling among many thousands of purple progeny. BC1 segregation ratios were calculated to characterize how various natural LON species carry p on their two genomes. We envision that this recessive mutant could be a useful tool for several types of research: Tracking geneflow and dispersion in S. fendleri and other LON populations, studies of pollinator behavior in the wild, and gene expression interactions between homeologous genomes.