2026-04-13T06:33:10Zhttps://recercat.cat/oai/requestoai:recercat.cat:20.500.12327/36862025-10-22T11:01:43Zcom_2072_4428com_2072_4427col_2072_487898
RECERCAT
author
Aletà, Neus
author
Ninot, Antonia
author
Voltas, J.
other
Producció Vegetal
group
Fructicultura
2025-10-22T11:01:43Z
2025-10-22T11:01:43Z
2004
Aletà, N., A. Ninot, and J. Voltas. 2004. “Retrospective Evaluation of Parental Selection in Nursery Tests of Juglans Regia L. Using a Mixed Model Analysis.” Silvae Genetica 53 (1-6): 26-33. doi: 10.1515/sg-2004-0005
0037-5349
http://hdl.handle.net/20.500.12327/3686
https://doi.org/10.1515/sg-2004-0005
Results of early testing in Juglans regia performed over the
period 1993–2002 are presented. A total of 37 progenies were
evaluated for establishment, growth traits, and phenology at
ages one and two during two or more sowing years in the nursery. Independent culling selection was applied on parental
trees to the family-mean values using specific truncation points
for establishment, diameter and total height. In addition,
parental selection was performed on unbiased predictions
(BLUPs) of parental breeding values using a multivariate
mixed model analysis in order to account for the unbalanced
nature of the entire data set. Genetic parameters (heritabilities, correlations) of juvenile traits were also estimated. Except
for second year growth traits, the genetic control of most characters was quite high, with heritability estimates ranging from
0.51 (establishment) to 0.93 (flushing date). Growth performance and establishment did not bear a common genetic control according to non-significant genetic correlations, but a
higher growth was typical of early flushing families. Changes
in parental ranking for growth after comparison of familymean and BLUP-based estimates of parental performance were
considerable. This observation, together with the larger proportion of culled progenies in the former method (about 70%), suggests a sizeable loss of genetic gain by using unadjusted
parental means. It is concluded that current evaluation and
selection schemes using family-mean values should be reconsidered by i) relaxing truncation points for selection on establishment and growth traits and ii) re-evaluating progeny test
data using a mixed model framework to unveil valuable material otherwise neglected due to unaccounted environmental
influence on family performance
eng
Attribution-NonCommercial-NoDerivatives 4.0 International
Retrospective Evaluation of Parental Selection in Nursery Tests of Juglans regia L. Using a Mixed Model Analysis
info:eu-repo/semantics/article