Research article

Diversity in needle morphology and genetic markers in a marginal Abies cephalonica (Pinaceae) population

Aristotelis C. Papageorgiou , Chrysoula Kostoudi, Ioannis Sorotos, Georgios Varsamis, Georgios Korakis, Andreas D. Drouzas

Aristotelis C. Papageorgiou
Department of Forestry, Environmental Management and Natural Resources, Democritus University of Thrace, Pantazidou 193, GR-68200 Orestiada, Greece. Email:
Chrysoula Kostoudi
Department of Forestry, Environmental Management and Natural Resources, Democritus University of Thrace, Pantazidou 193, GR-68200 Orestiada, Greece
Ioannis Sorotos
Department of Forestry, Environmental Management and Natural Resources, Democritus University of Thrace, Pantazidou 193, GR-68200 Orestiada, Greece
Georgios Varsamis
Department of Forestry, Environmental Management and Natural Resources, Democritus University of Thrace, Pantazidou 193, GR-68200 Orestiada, Greece
Georgios Korakis
Department of Forestry, Environmental Management and Natural Resources, Democritus University of Thrace, Pantazidou 193, GR-68200 Orestiada, Greece
Andreas D. Drouzas
Department of Botany, School of Biology, Aristotle University of Thessaloniki, GR-54124, Greece

Online First: June 29, 2015
Papageorgiou, A., Kostoudi, C., Sorotos, I., Varsamis, G., Korakis, G., Drouzas, A. 2015. Diversity in needle morphology and genetic markers in a marginal Abies cephalonica (Pinaceae) population. Annals of Forest Research DOI:10.15287/afr.2015.410

Differences in needle traits of coniferous tree species are considered as the combined result of direct environmental pressure and specific genetic adaptations. In this study, diversity and differentiation within and among four Abies cephalonica subpopulations of a marginal population on Mt. Parnitha - Greece, were estimated using needle morphological traits and gene markers. We tested the connection of morphological variability patterns of light and shade needles with possible adaptation strategies and genetic diversity. Six morphological characteristics were used for the description of both light and shade needles at 100 trees, describing needle size and shape, stomatal density and needle position on the twigs. Additionally, six RAPD and three ISSR markers were applied on DNA from the same trees. Light needles were significantly different than shade needles, in all traits measured, apparently following a different light harvesting strategy. All four subpopulations exhibited high genetic diversity and the differentiation among them was relatively low. Differences among populations in light needles seemed to depend on light exposure and aspect. In shade needles, the four subpopulations seemed to deviate stronger from each other and express a rather geographic pattern, similarly to the genetic markers. Two of the subpopulations studied were lost during a wildfire, two years after sampling. Although the subpopulations burnt were most diverse and most differentiated, we expect a large part of the total genetic diversity of the burnt trees to still exist in the surviving subpopulations, since gene flow must have been effective in keeping all subpopulations connected.

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