Somatic hybrids have been obtained between potato and Solanum bulbocastanum
PI 245310, a Mexican diploid (2n=2x=24) species. Through restriction fragm
ent length polymorphism (RFLP) and randomly amplified polymorphic DNA (RAPD
) analyses it was found that the somatic hybrids contain each chromosome of
the diploid parent and that the synteny of RFLP markers noted with tomato,
potato and S. brevidens is largely maintained in S. bulbocastanum. RFLP an
alyses of BC I progeny of two different hybrids indicated that a substantia
l number of markers were either lost or were heterozygous, in marked contra
st with results previously noted with S. brevidens. A RAPD map for all 12 c
hromosomes of S. bulbocastanum was prepared and marker transmission was fol
lowed in three BC2 populations. Results with chromosomes 3, 8 and 10 from t
hese populations are compared.