CYTOPLASMIC MALE STERILITY IN INTERSPECIFIC HYBRIDS BETWEEN AMERICAN AND ASIAN CASTANEA SPECIES IS CORRELATED WITH THE AMERICAN D CHLOROPLAST HAPLOTYPE

Cytoplasmic male sterility (CMS) is present in progeny of interspecific crosses between American and Asian Castanea species.
F₁ progeny of C. dentate as female × C. mollissima as male are almost always male sterile, whereas F₁ progeny of the reciprocal cross are male fertile.
There are, however, exceptions to this general rule.
These exceptional C. dentata × C. mollissima trees are male fertile rather than male sterile.
Analysis of the trnV-ndhC region of chloroplast DNA (cpDNA) of both male sterile and male fertile F₁ hybrids of C. dentata × C. mollissima demonstrated that male sterility was correlated with the American chestnut D chloroplast haplotype while fertile hybrids of the same genotype had either the P or M chloroplast haplotype.
This variation in male fertility in hybrids of C. dentata × C. mollissima may be caused by the interaction of nuclear genes from C. mollissima with genes encoded in the mitochondria inherited from C. dentate, because in other species CMS has been found to be associated with variations in mtDNA. This assumes that the mitochondrial DNA (mtDNA) haplotype associated with D chloroplasts is different from the mitochondrial haplotype(s) associated with the P and M chloroplasts.
This is an example of the effect of cytoplasmic haplotype on a whole tree phenotype.

V International Chestnut Symposium

P.H. Sisco, T.C. Neel, F.V. Hebard, J.H. Craddock, J. Shaw

chloroplast DNA, cpDNA, mitochondrial DNA, mtDNA, cytoplasmic genotype

https://doi.org/10.17660/ActaHortic.2014.1019.32