Inheritance and genetic mapping of tuber eye depth in cultivated diploid potatoes

Tuber eye depth of the potato (Solanum tuberosum L.) is an important trait for the processing quality and appearance of potatoes. In the present study, we used a cultivated diploid potato family (12601) of 107 plants to dissect the mode of inheritance and to map the gene(s) controlling the trait. The family segregated for both eye depth (deep vs shallow) and tuber shape (round vs long) traits. The deep eye (Eyd) phenotype was found to be associated with round tubers (Ro) in most progeny clones. Further evaluation of this population with molecular markers including simple sequence repeats, amplified fragment length polymorphism, and sequence-characterized amplified regions revealed that the primary locus for eye depth is located on chromosome 10. This map location was confirmed by evaluating a second diploid family (12586). The results of this study led to the following conclusions: (1) there is a major locus controlling the eye depth trait; (2) deep eye (Eyd) is dominant to shallow (eyd); (3) the Eyd/eyd locus is located on chromosome 10; and (4) the Eyd/eyd locus is closely linked with the major locus for tuber shape (Ro/ro), at a distance of about 4 cM.