Gr. Hodge et al., A COMPARISON OF GENETIC INFORMATION FROM OPEN-POLLINATED AND CONTROL-POLLINATED PROGENY TESTS IN 2 EUCALYPT SPECIES, Theoretical and Applied Genetics, 92(1), 1996, pp. 53-63
Genetic-parameter estimates and parental breeding-value predictions we
re compared from open-pollinated and control-pollinated progeny popula
tions of Eucalyptus globulus and two populations of E. nitens. For E.
globulus there were two types of open-pollinated populations (native s
tand open-pollinated and seed orchard open-pollinated) and two types o
f control-pollinated populations (intra-provenance and inter-provenanc
e full-sib families). For E. nitens there were two populations, a seed
orchard open-pollinated population and intra-provenance full-sib fami
lies. Progeny tests were established across multiple sites and 2-year
height and diameter were measured and volume calculated. Genetic param
eters from native stand open-pollinated E. globulus were unlike the pa
rameters from the other three E. globulus populations; heritability es
timates were severely inflated, presumably due to high levels, and pos
sibly differential levels, of inbreeding depression relative to the ot
her populations. Estimates of dominance variance in the E. globulus fu
ll-sib populations were high, but were zero in the E. nitens populatio
n. Correlations among parental breeding values, predicted using data f
rom the different populations, were generally low and non-significant,
with two exceptions: predictions from the two E. globulus full-sib po
pulations were significantly correlated (r=0.54, P=0.001), as were pre
dictions from the E. nitens seed orchard OP and full-sib population (r
=0.61, P=0.08). There was some indication that superior parents of E.
globulus native stand open-pollinated families also tended to have abo
ve-average breeding values based on the performance of intra-provenanc
e full-sib offspring. The consequences of these results for exploitati
on of base-population collections from native stands are discussed.