Data from: Genetic parameters in subtropical pine F1 hybrids: heritabilities, between-trait correlations and genotype-by-environment interactions

Growth and stem straightness traits of 29 Pinus caribaea var.
hondurensis × Pinus tecunumanii (PCH × PTEC) and 26 P. caribaea var.
hondurensis × Pinus oocarpa (PCH × POOC) hybrid pair-crosses plus a total
of 16 intraspecific families were assessed at ages 5, 8 and 15 years from
planting at two sites. The PCH × PTEC hybrid was the most productive,
yielding 37 % more than a Pinus elliottii local control and was 21 %
superior to either parental species in DBH growth. PCH × POOC hybrid was,
on average, 16 % superior to either parental species for DBH. Narrow-sense
heritability estimates were low to moderate for growth traits (average of
0.27) and stem straightness (0.16). The estimated additive genetic
correlations between growth traits and ages within traits were high
(>0.8) and positive, providing confidence in early selection based
on diameter at breast height. The high proportion of estimated additive
genetic variance compared to dominance variance in the F1 pine hybrids
suggests that breeding strategies that maximize the use of additive
genetic variance may be effective. The ranking of the 11 PCH parents based
on general hybridizing ability predictions (estimated breeding values as
hybrids) was somewhat inconsistent between PTEC and POOC hybrid crosses
for all traits (r 9 d.f. = 0.38–0.45; p ∼0.15–0.25). There was no evidence
of practically important G × E interaction for the hybrids except for
PCH × PTEC height growth. This study suggests that a single, multi-hybrid
breeding population seems appropriate in Zimbabwe if the trial sites are
representative of the planting target zone.