Characterization of Crossability in the Crosses between Solanum demissum and S. tuberosum, and the F1 and BC1 Progenies

Abstract

The Endosperm Balance Number (EBN) assigned to each species can foresee success or failure of a given interspecific cross in potatoes, although the underlying molecular basis is poorly studied. We found that the cross of Solanum demissum as female with a breeding line Saikai 35 constantly produced larger seeds (0.94 mg) than those from the reciprocal cross (0.39 mg), suggesting a slightly lower EBN in S. demissum. Crossing behaviors, measured by berry-setting rates, seeds/berry and seed size, in the reciprocal F1 and BC1 progenies suggest at least three genetic factors involved in normal seed development: 1) a cytoplasmic factor, and nuclear genome-encoded factors functioned 2) in female gametophyte and 3) in pollen. Thus, these materials are useful in exploring the molecular mechanism of EBN, because the degree of imbalanced EBN could be measured as quantitative traits.