Interspecific Hybrids Between × and Species From Section Reveal Biparental Plastid Inheritance and Multi-Locus Cyto-Nuclear Incompatibility.

The genetics underlying Cyto-Nuclear Incompatibility (CNI) was studied in interspecific hybrids. We created hybrids of 12 closely related crop wild relatives (CWR) with the ornamental × . Ten of the resulting 12 (F) interspecific hybrids segregate for chlorosis suggesting biparental plastid inheritance. The segregation ratios of the interspecific F populations show nuclear interactions of one, two, or three nuclear genes regulating plastid function dependent on the parents. We further validated that biparental inheritance of plastids is common in section , using diagnostic PCR primers. Our results pave the way for using the diverse species from section , each with its own set of characteristics, as novel sources of desired breeding traits for × cultivars.