Data from: Genotype by environment interaction for growth and Dothistroma resistance and clonal connectivity between environments in radiata pine in New Zealand and Australia

Twenty-eight clonal trials of radiata pine planted across Australia and
New Zealand were used to investigate genetic variation and genotype by
environment (G×E) interaction for diameter-at-breast-height (DBH), height
and Dothistroma resistance (DO_R). The average narrow-sense heritabilities
were 0.11, 0.21 and 0.30 while the average broad-sense heritabilities were
0.27, 0.34 and 0.40 for DBH, height and Dothistroma resistance,
respectively. Dothistroma resistance was assessed as the percentage of
needles that were not affected by Dothistroma needle blight. G×E
interactions were analysed using an approximate reduced factor analytic
model. Apparent G×E interactions were estimated for DBH, height and
Dothistroma resistance. Estimates of G×E interactions and their standard
errors were strongly influenced by the level of connectivity between
trials, in terms of common clones and common parents. When there was
sufficient connectivity between trials (more than 30% common clones
between trials), a high level of G×E interaction was found for DBH and
height but not for Dothistroma resistance. In two simulated clonal trials
planted in two environments, low connectivity between environments
resulted in a lower estimated genetic correlation between environments
with an increased standard error. These results suggest that the number of
clones in common between clonal trials is a key factor for inclusion in
future experimental designs for estimating G×E interaction. When designing
clonal trials for use in multiple environments for accurately estimating
the level of G×E, if the resource for creating connectivity between
environments is limited, at least 30% of the clones need to be in common
between environments.