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Local adaptation of microscopic stages of North Atlantic Laminaria digitata to high and low temperatures along latitudes: survival, reproduction and growth

To assess the thermal adaptation of microscopic stages of the kelp Laminaria digitata along latitudes, we conducted laboratory experiments on samples from six locations in the NE Atlantic (Spitsbergen (SPT), Tromsø (TRM), Bodø (BOD; all Norway), Helgoland (HLG; Germany), Roscoff (ROS) and Quiberon (QUI; both France)), spanning the species' entire distribution range. In experiment 1, we exposed gametophytes to (sub-) lethal high priming temperatures (20-25°C) for two weeks, followed by two weeks of recovery at 15°C, to observe gametophyte survival and sporophyte formation. In experiment 2, samples were subjected to (sub-) optimal low temperatures (0-15°C) for 21 days, to assess gametophyte survival, sporophyte formation and growth. During the experiments, samples were kept in 15 µmol photons/m²/s white light under a 16:8h light:dark cycle. Prior to the experiments, cultures were stored at 15°C in iron-free ½ Provasoli enriched seawater in 3-4 µmol photons/m²/s red light.

Laminaria digitata gametophyte survival and microscopic sporophyte formation, abundance and growth during exposure to decreased temperatures

To assess the thermal adaptation of microscopic stages of the kelp Laminaria digitata along latitudes, we conducted laboratory experiments on samples from six locations in the NE Atlantic (Spitsbergen (SPT), Tromsø (TRM), Bodø (BOD; all Norway), Helgoland (HLG; Germany), Roscoff (ROS) and Quiberon (QUI; both France)), spanning the species' entire distribution range. Gametophyte stock cultures from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research were used. Prior to the experiments, cultures were stored at 15°C in iron-free ½ Provasoli enriched seawater in 3-4 µmol photons/m²/s red light. In experiment 2, samples were subjected to (sub-) optimal low temperatures (0-15°C) for 21 days, to assess gametophyte survival, sporophyte formation and growth. During the experiments, samples were kept in 15 µmol photons/m²/s white light under a 16:8h light:dark cycle. Sporophyte growth rates both in length and in width were determined as follows: GR = (x2-x1)/(t2-t1), where x is the length or width (μm) and t is the time in weeks at time point 1 and 2.

Laminaria digitata gametophyte survival and sporophyte formation during exposure to increased temperatures

To assess the thermal adaptation of microscopic stages of the kelp Laminaria digitata along latitudes, we conducted laboratory experiments on samples from six locations in the NE Atlantic (Spitsbergen (SPT), Tromsø (TRM), Bodø (BOD; all Norway), Helgoland (HLG; Germany), Roscoff (ROS) and Quiberon (QUI; both France)), spanning the species' entire distribution range. Gametophyte stock cultures from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research were used. Prior to the experiments, cultures were stored at 15°C in iron-free ½ Provasoli enriched seawater in 3-4 µmol photons/m²/s red light. In experiment 1, we exposed gametophytes to (sub-) lethal high priming temperatures (20-25°C) for two weeks, followed by two weeks of recovery at 15°C, to observe gametophyte survival and sporophyte formation. During the experiments, samples were kept in 15 µmol photons/m²/s white light under a 16:8h light:dark cycle.

Integrated survival of Laminaria digitata gametophytes exposed to increased temperatures

To assess the thermal adaptation of microscopic stages of the kelp Laminaria digitata along latitudes, we conducted laboratory experiments on samples from six locations in the NE Atlantic (Spitsbergen (SPT), Tromsø (TRM), Bodø (BOD; all Norway), Helgoland (HLG; Germany), Roscoff (ROS) and Quiberon (QUI; both France)), spanning the species' entire distribution range. Gametophyte stock cultures from the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research were used. Prior to the experiments, cultures were stored at 15°C in iron-free ½ Provasoli enriched seawater in 3-4 µmol photons/m²/s red light. In experiment 1, we exposed gametophytes to (sub-) lethal high priming temperatures (20-25°C) for two weeks, followed by two weeks of recovery at 15°C, to observe gametophyte survival and sporophyte formation. During the experiments, samples were kept in 15 µmol photons/m²/s white light under a 16:8h light:dark cycle.

Pimpinella saxifraga analysis without treatment conditions eight or more years after restoration

Pimpinella saxifraga analysis with treatment conditions eight or more years after restoration

Basic analysis of Pimpinella saxifraga

Genotypic and phenotypic distinctness of restored and indigenous populations of Pimpinella saxifraga eight or more years after restoration

Formerly, non-local seed sourcing of naturally occurring herbaceous species was the main strategy for ecological restoration in Germany. Prices for non-local seeds were significantly lower and large quantities of local seeds were unavailable. We here tested whether the genetic composition of non-local seeds (R) of Pimpinella saxifraga L. (Apiaceae) of former restoration projects can still be detected several years after application and whether it differs from the species' regional gene pool (I). A comparative population genetic analysis (AFLP) was conducted. In a common garden experiment phenological and morphological differences were investigated. We further simulated mowing to investigate, if treatments affect indigenous (I) and restored (R) populations differently. The population genetic analysis resulted in two large and quite distinct and diverse cluster that separated I- and R-site individuals, with some signatures of introgression from R to I. Three generative fitness parameters featured significant differences between individuals of the R- and I-sites. The genotypic persistence reduces the availability of niches for the local genotype and may eventually lead to genotypic competition or introgression. We therefore recommend to retain from the introduction of the species' non-local genotypes in the region to avoid genotypic competition and recommend to use the genetically diverse local genotypes for restoration purposes. Data collection time: 2011.09.01 until 2013.11.30 In a comparative approach, we tested whether the genetic makeup of the former non-local seed source use of Pimpinella saxifraga L. (Apiaceae) in restoration projects at sites in Central Germany several years after application (restoration between 1994 and 2004) differs from the species' regional gene pool. In a comparative approach, we compared genetic diversities and differentiations by using amplified fragment length polymorphisms (AFLPs). Phenological and morphological differences were analyzed in a common garden experiment in which we cultivated plants from all sites. For that we sampled seed and plant material in autumn 2011 of seven populations per I- and R-site. Of each individual of each study site 60 seeds were sown in a common garden experiment at the Universities nursery in Giessen (Germany) in spring 2012. The data collections of generative and vegetative morphological variation were measured two times per week in 2013 throughout the season.

LinkTree - Bedeutung der genetischen Variabilität von Waldbäumen für Anpassungsprozesse, Teilprojekt: Untersuchungen zur Variabilität von Kandidatengenen bei der Weißtanne

Ziel des Vorhabens: Ziel des Vorhabens LinkTree ist es, Waldbäume als Modellsysteme (keystone species der Waldökosysteme und foundation species in organismischen Interaktionen) zu nutzen, um erstmalig Beziehungen zwischen der Variation an stressrelevanten Kandidaten-Genen mit denen kleinräumiger Umweltvariation systematisch sowohl in wiederholten natürlichen Umweltgradienten als auch im Common-Garden-Experiment zu untersuchen. Modelle sind die in Europäischen Waldökosystemen weit verbreiteten Gattungen Pinus, Abies, Picea und Quercus. Stressfaktoren sind in erster Linie Trockenheit und Feuer und damit solche, für die im Rahmen des Globalen Wandels und im jetzigen Verbreitungsgebiet der Arten eine noch zunehmende Stresswirkung erwartet werden kann. P5 UNI-MAR: 1. (siehe auch WP1 des Proposals):Max.1000 Gene werden für die Tanne charakterisiert 2. (siehe auch WP2 des Proposals): Davon werden a. 140 Gene bzw. 384 SNPs (kompatibel für 96-well) entlang eines Höhengradienten auf Variation geprüft und Absaaten von Trägern bestimmter Varianten in Nachkommenschaftstest - common garden experiments - geprüft. Publikationen, Kongresse, Modelle und Richtlinien für die Forstwirtschaft

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