Gl. Sun et al., Microsatellite and RAPD polymorphisms in Ontario corn hybrids are related to the commercial sources and maturity ratings, MOL BREED, 7(1), 2001, pp. 13-24
Random-amplified polymorphic DNA (RAPD) and microsatellite markers were use
d to estimate the genetic relationships among 37 Ontario corn hybrids. Almo
st all (95%) of the 160 RAPD fragments and all of the 79 microsatellite all
eles were polymorphic across the 37 hybrids. Similarity values among the hy
brids ranged from 31% to 86% when based on the RAPD data. The similarities
based on microsatellite markers ranged from 12% to 77%. The genetic diversi
ty revealed by microsatellite marker analysis was higher than that obtained
fro RAPD analysis. The similarity matrices for the microsatellite data and
the RAPD data were moderately correlated (0.43). Cluster analyses based on
either type of marker showed that most oaf the hybrids from the same compa
ny were closely related to each other. Both dendrograms clustered similar p
airs or groups of hybrids. A principal component analysis, based on the com
bined RAPD and microsatellite data, yielded a good separation of the hybrid
s with Ontario Corn Heat Unit (OCHU) values <2800 from those with OCHU valu
es >2800. Seventeen RAPD markers and 5 microsatellite markers were signific
antly associated with the OCHU ratings of the hybrids.