Tuber Calcium Accumulation in the Wild Potato Solanum Microdontum

Solanum microdontum (mcd) is a tuber-bearing relative of commercial potato. Although wild, it has many attractive traits for breeding. Previous research has shown it has exceptional ability to sequester calcium in its tubers, a trait associated with tuber disease resistance and tuber quality. We used a set of mcd from 50 populations in the US Potato Genebank (USPG) shown to encompass most of the genetic diversity in the species, two individuals from each population. Tubers were produced in pots in the USPG greenhouse in two years, and freeze dried samples tested for calcium content. Some exceptionally high Ca accumulators were identified (especially clone mcd40B1 from PI 473166). Because other minerals were measured in the same tests, the highest accumulators for K, Mg, Zn in mcd were also identified. All the stocks tested are available in vitro from USPG for additional research and breeding.