Advisor(s)
Abstract(s)
Cork oak (Quercus suber L.) has a high ecological and social value and supplies raw materials for the cork
industry, a relevant contributor to the economies of Mediterranean countries. Understanding the adaptation
potential of cork oak populations to cope with different environmental conditions is a key issue of forest
management, particularly for selecting the most adapted genetic material for (re)forestation and assuring the
long-term sustainability of the cork industry. Intraspecific variation in fitness surrogate traits (survival, height
and stem diameter) was investigated in thirty-five cork oak populations sampled from the entire range of the
natural distribution of the species. The study was conducted in two provenance field trials, established in
Portugal under different edaphoclimatic conditions. Each trial was surveyed at four tree ages (two ages, 11 and
14 years, were sampled simultaneously in both trials). The trial located at a lower altitude, which had higher
mean winter and annual temperatures, exhibited higher growth and survival rates. In both trials, significant
genetic variation among cork oak populations was observed for the analyzed traits and evaluated ages. Moroccan
populations displayed a higher probability of survival and higher growth rates, while local populations exhibited
an intermediate performance. Low to moderate correlations were found between the analyzed traits and the
environmental variables of seed origin, suggesting that factors other than climate are likely to be relevant for
cork oak adaptation. Moderate to high values of population mean-basis broad-sense heritability (H2≥0.44) and
high genetic correlations between traits (0.88–0.95) were found for growth traits. This information is crucial for
the establishment of a breeding program for the species. With this study, we have improved the knowledge
regarding how cork oak performs for fitness surrogate traits in different environments.
Description
Keywords
Fitness surrogate traits Local adaptation Mediterranean oak Mixed models Population variation Provenance trials
Pedagogical Context
Citation
Sampaio, Teresa; Gonçalves, Elsa; Patrício, Maria S.; Cota, Tânia M.; Almeida, M. Helena (2019). Seed origin drives differences in survival and growth traits of cork oak (Quercus suber L.) populations. Forest Ecology and Management. ISSN 0378-1127. 448, p. 267-277