P. Revilla et Wf. Tracy, HETEROTIC PATTERNS AMONG OPEN-POLLINATED SWEET CORN CULTIVARS, Journal of the American Society for Horticultural Science, 122(3), 1997, pp. 319-324
Heterotic patterns in sweet corn are weakly defined, Most sweet corn i
nbreds are descended from three open-pollinated cultivars: 'Golden Ban
tam', Stowell's Evergreen', and 'Country Gentleman'. Heterotic and phy
logenetic relationships among these three cultivars and others are not
clearly known, This investigation was designed to investigate the het
erotic patterns among some historically important open-pollinated swee
t corn cultivars: 'Country Gentleman', 'Golden Bantam','Lindsey Meyer
Blue','Stowell's Evergreen','Howling Mob', and 'Pease Crosby', The 15
possible hybrids from the diallel cross plus the 6 parents were grown
in midspring and late summer plantings. Heterosis and combining abilit
y effects were estimated for 13 traits, Hybrid x planting date interac
tions mere significant for most of the main traits, hence, planting da
tes were analyzed separately, Average midparent heterosis for grain yi
eld was 29.17% in the first planting date and 57.04% in the second pla
nting. Midparent heterosis for yield and plant height were highest for
hybrids with 'Country Gentleman' as a parent, 'Stowell's Evergreen' w
hen crossed to 'Pease Crosby', 'Lindsey Meyer, and 'Golden Bantam' exh
ibited high heterosis, The two late-maturity cultivars 'Country Gentle
man' and 'Stowell's Evergreen' had higher general combining ability th
an the four early-maturity cultivars for most traits, Specific combini
ng ability was seldom significant, Yield of 'Country Gentleman' hybrid
s averaged over all crosses and planting dates was the highest, These
data indicate a strong heterotic pattern-'Country Gentleman' x 'Pease
Crosby', 'Golden Bantam', and 'Lindsey Meyer Blue'-and a weaker one-'S
towell's Evergreen' x 'Pease Crosby','Golden Bantam', and 'Lindsey Mey
er Blue'.