The current global crisis of biodiversity loss calls for urgent conservation actions for many species, not the least wild species related to crop plants. These crop wild relatives are considered harbouring genetic diversity of major importance for future crop plant improvement, e.g. adaptation to climate change. Hence, their conservation needs to be a priority. To ensure the long-term conservation and to maximize the utility value of these species, it is important that as much of their genetic diversity as possible is conserved. Thus, the distribution of intraspecific diversity must be taken into consideration when planning conservation efforts. Caraway, Carum carvi L., has been cultivated since medieval times and is today one of the most important spice crops worldwide. In order to identify populations that would be of particular interest for in situ and ex situ conservation and for use in plant breeding we evaluated the geographic distribution of intraspecific diversity in populations of Carum carvi in the Nordic region (Iceland, Denmark, Norway, Sweden and Finland). Using a genotyping by sequencing approach, we genotyped 198 individuals from 16 Nordic populations. The amount of intrapopulation genetic diversity was similar among populations (mean He = 0.29), and the diversity was structured in an east-westerly manner, probably reflecting colonisation patterns associated with different glacial refugia. In addition, some populations likely have a history shaped by human interventions. The results have important conservation implications and based on the outcome of this study, populations of conservation priority are suggested.

Hordeum vulgare var. nudum (naked barley) is one of the oldest and most common cereals found from Neolithic Fennoscandia. After the Bronze Age, naked barley largely disappeared and was replaced by Hordeum vulgare var. vulgare (hulled barley) and other cereals. During the early 19th century, naked barley of Asian origins was reintroduced to Fennoscandia. In this study, we have genetically characterized samples of Fennoscandian landraces of naked barley which were preserved in gene banks and museum collections. The analyses show that the Fennoscandian naked barley can be split into three groups: First, naked two-row barley, with a likely origin in Asia; second, naked six-row barley, with a likely origin in the eastern Himalayas and introduced during the 19th century; third, naked six-row barley genetically related to the original Fennoscandian hulled barley. The results suggest that this last group represents the ancient form of naked barley, which was possibly introduced in the Neolithic. At that time both naked and hulled barleys were grown and enough gene flow probably occurred between these two subspecies to create a Fennoscandian barley that is genetically distinct, irrespective of whether it is hulled or naked. This hypothesis was further supported by genotyping of the Nud gene, which is responsible for the naked phenotype. All naked barleys which we studied contained the same mutation allele, nud1.a, thus showing that naked Fennoscandian barley arose by crossings between naked and hulled barley and not by new mutations of hulled barley.

During the 19th century, Chevalier, said to have been developed from a single plant found in 1820, was the world-leading malting barley (Hordeum vulgare). The superior malting quality of Chevalier lead to its world-wide spread at the time of the development of the malting industry. In this study, we investigate how this cultivar was spread and adopted to Nordic seed systems of the time. Single nucleotide polymorphism genotyping of up to 155-yr-old museum specimens of historical grains labelled "Chevalier" and of Chevalier accessions preserved in genebanks, in total 282 individuals representing 47 accessions, allowed us to divide the accessions into four categories: True Chevalier, seed mixtures, crosses, and non-Chevaliers. Comparisons with previously genotyped Nordic landraces showed how, in the 19th century, Chevalier seed was mixed with locally produced landrace seed and cultivated together. We suggest that spontaneous outbreeding events gave rise to hybrids which were subsequently selected and propagated when resulting in superior genetic combinations. Such farmer-driven breeding activities would have preceded modern plant breeding but resembled the breeding principles that were later used, even though the scientific understanding of inheritance was not yet known.

I det här kapitlet betonar vi gruppdiskussioners betydelse för att aktivera studenter och gynna deras lärande. Undervisningen på kursen "Evolution" bedrevs omväxlande i traditionell undervisningssal och i ALC. Tyngdpunkten på kursen ligger på studenternas gruppdiskussioner. Fokus i kapitlet ligger på de aktiviteter som studenterna genomför i ALC.

In Northern Europe, barley (Hordeum vulgare L.) has been cultivated for almost 6000 years. Thus far, 150-year-old grains from historical collections have been used to investigate the distribution of barley diversity and how the species has spread across the region. Genetic studies of archaeobotanical material from agrarian sites could potentially clarify earlier migration patterns and cast further light on the origin of barley landraces. In this study, we aimed to evaluate different archaeological and historical materials with respect to DNA content, and to explore connections between Late Iron Age and medieval barley populations and historical samples of barley landraces in north-west Europe. The material analysed consisted of archaeological samples of charred barley grains from four sites in southern Finland, and historical material, with 33 samples obtained from two herbaria and the seed collections of the Swedish museum of cultural history.

The DNA concentrations obtained from charred archaeological barley remains were too low for successful KASP genotyping confirming previously reported difficulties in obtaining aDNA from charred remains. Historical samples from herbaria and seed collection confirmed previously shown strong genetic differentiation between two-row and six-row barley. Six-row barley accessions from northern and southern Finland tended to cluster apart, while no geographical structuring was observed among two-row barley. Genotyping of functional markers revealed that the majority of barley cultivated in Finland in the late nineteenth and early twentieth century was late-flowering under increasing day-length, supporting previous findings from northern European barley.

Around the world, there are more than 1500 genebanks storing plant genetic resources to

be used in breeding and research. Such resources are essential for future food security, but many genebanks experience backlogs in their conservation work, often combined with limited budgets. Therefore, avoiding duplicate holdings is on the agenda. A process of coordination has started, aiming at sharing the responsibility of maintaining the unique accessions while allowing access according to the international treaty for plant genetic resources. Identifying duplicate holdings based on passport data has been one component of this. In the past, and especially in vegetables, different selections within the same varieties were common and the naming practices of cultivars/selections were flexible. Here, we examined 10 accession pairs/groups of cabbage (Brassica oleracea var. capitata) with similar names maintained in the Russian and Nordic genebanks. The accessions were analyzed for 11 morphological traits and with a SNP (Single Nucleotide Polymorphism) array developed for B. napus. Both proved to be useful tools for understanding the genetic structure among the accessions and for identifying duplicates, and a subset of 500 SNP markers are suggested for futureBrassica oleracea genetic characterization. Within five out of 10 pairs/groups, we detected clear genetic differences among the accessions, and three of these were confirmed by significant differences in one or several morphological traits. In one case, a white cabbage and a red cabbage had similar accession names. The study highlights the necessity to be careful when identifying duplicate accessions based solely on the name, especially in older cross-pollinated species such as cabbage.

Barley has been continuously cultivated in the Canary archipelago for millennia, and to this day landrace barley is the preferred choice for cultivation. We have morphologically and genetically characterized 57 landraces collected during the twenty-first century and conserved in genebanks. The majority of accessions were of the six-row type. Although landraces from the same island tended to be similar, the results showed morphological and genetic diversity both within and in the case of genetic data among islands. Accessions from the easternmost islands were genetically distinct from those from the central and western islands. Accessions from the western islands often had a mixed genetical composition, suggesting more recent exchange of plant material with the central islands. The geographic distribution of diversity suggests that conservation of barley genetic resources needs to consider all islands in the archipelago. Landrace barley from the Canary archipelago was found to be morphologically distinct from continental landrace barley. We suggest the uniqueness of Canarian barley, in terms of morphology and genetic diversity, can be used for marketing purposes providing added market value to the crop.

Background: The observation that many alien species become invasive despite low genetic diversity has long been considered the ‘genetic paradox’ in invasion biology. This paradox is often resolved through the temporal buildup genetic diversity through multiple introduction events. These temporal dynamics in genetic diversity are especially important for annual invasive plants that lack a persistent seed bank, for which population persistence is strongly dependent on consecutive seed ‘re-establishment’ in each growing season. Theory predicts that the number of seeds during re-establishment, and the levels of among-population gene flow can strongly affect recolonization dynamics, resulting in either an erosion or build-up of population genetic diversity through time. This study focuses on temporal changes in the population genetic structure of the annual invasive plant Impatiens glandulifera across Europe. We resampled 13 populations in 6 regions along a 1600 km long latitudinal gradient from northern France to central Norway after 5 years, and assessed population genetic diversity with 9 microsatellite markers.

Results: Our study suggests sufficiently high numbers of genetically diverse founders during population re- establishment, which prevent the erosion of local genetic diversity. We furthermore observe that I. glanduliferaexperiences significant among-population gene flow, gradually resulting in higher genetic diversity and lower overall genetic differentiation through time. Nonetheless, moderate founder effects concerning population genetic composition (allele frequencies) were evident, especially for smaller populations.

Despite the initially low genetic diversity, this species seems to be successful at persisting across its invaded range, and will likely continue to build up higher genetic diversity at the local scale.

The report summarizes results from a cooperation among all the Nordic countries during the period 2015 – 2019 (two projects). The work has focused on the conservation of Crop Wild Relatives (CWR), i.e. wild plant species closely related to crops. They are of special importance to humanity since traits of potential value for food security and climate change adaptation can be transferred from CWR into crops. The projects represent the first joint action on the Nordic level regarding in situ conservation of CWR. Substantial progress has been made regarding CWR conservation planning, including development of a Nordic CWR checklist and identification of suitable sites for CWR conservation. A set of recommended future actions was developed, with the most important one being initiation of active in situ conservation of CWR in all Nordic countries.

Rye (Secale cereale L.) was for centuries the economically most important crop in Fennoscandia (Denmark, Finland, Norway and Sweden). Historical records tell of a range of different types adapted to climate and varying cultivation practices. Genetic analyses of genebank maintained landrace rye have yet failed, with a few exceptions, to detect differentiation between rye types. Concerns have been raised that genebank material does not truly reflect the historical variation in landrace rye. In this study, we have therefore genotyped old and historical samples of rye as well as extant material. Two historical seventeenth century samples were obtained from a grave and a museum archive respectively, and 35 old samples were taken from 100 to 140-year-old seed collections and museum artefacts made of straw. We could confirm the results of previous studies suggesting Fennoscandian landrace rye to be one major meta-population, genetically different from other European rye landraces, but with no support for slash-and-burn types of rye being genetically different from other rye landraces. Only small differences in genetic diversity and allele distribution was found between old landrace rye from museum collections and extant genebank accessions, arguing against a substantial change in the genetic diversity during twentieth century cultivation and several regenerations during genebank maintenance. The genotypes of the old and historical samples suggest that the genetic structure of Fennoscandian landrace rye has been relatively stable for 350years. In contrast, we find that the younger samples and early improved cultivars belong to a different genetic group, more related to landraces from Central Europe.