| 1. |
- Aslan, Selcuk, et al.
(författare)
-
Molecular Genotyping of HistoricalBarley Landraces Reveals Novel CandidateRegions for Local Adaption
- 2015
-
Ingår i: Crop science. - : Crop Science Society of America. - 0011-183X .- 1435-0653. ; 55:6, s. 2766-2776
-
Tidskriftsartikel (refereegranskat)abstract
- Barley landraces from Northern Europe formgenetically distinct latitudinal groups, suggestingthat adaption plays an important role inthe geographical distribution of genetic diversity.Here, we investigate how Northern Europeanbarley landraces relate to landraces fromother parts of Europe and whether candidategenes for climate adaption can be identified.For this purpose, 27 barley landraces, availableas century-old seed specimens, were genotypedwith a 384 single nucleotide polymorphism(SNP) assay. Landraces from the Nordiccountries formed a genetically distinct grouprelative to landraces from Central and SouthernEurope. Polymorphic positions in the floweringtime genes HvCO1, HvFT1, Ppd-H1, and VRN1-H1 were genotyped. The previously known alleledistribution of Ppd-H1 with the responsive allelepresent in the South and the nonresponsiveallele in the North was confirmed. The otherthree genes were more variable in Central andSouthern Europe compared to the North andneither of the flowering time genes showedany geographically correlated variation withinthe Nordic countries. Allelic frequencies fromthe 384 SNP set were correlated with climaticvariables. This allowed us to identify five SNPsputatively associated with length of growth season,and two SNPs putatively associated withprecipitation. The results show how historicalcrop specimens can be used to study howgenetic variation has been geographically distributedand the genetics of adaption.
|
|
| 2. |
- Asplund, Linnea, et al.
(författare)
-
Allelic Variation at the Rht8 Locus in a 19th Century Wheat Collection
- 2012
-
Ingår i: Scientific World Journal. - : Hindawi Limited. - 1537-744X .- 2356-6140. ; , s. 385610-
-
Tidskriftsartikel (refereegranskat)abstract
- Wheat breeding during the 20th century has put large efforts into reducing straw length and increasing harvest index. In the 1920s an allele of Rht8 with dwarfing effects, found in the Japanese cultivar “Akakomugi,” was bred into European cultivars and subsequently spread over the world. Rht8 has not been cloned, but the microsatellite marker WMS261 has been shown to be closely linked to it and is commonly used for genotyping Rht8. The “Akakomugi” allele is strongly associated with WMS261-192bp. Numerous screens of wheat cultivars with different geographical origin have been performed to study the spread and influence of the WMS261-192bp during 20th century plant breeding. However, the allelic diversity of WMS261 in wheat cultivars before modern plant breeding and introduction of the Japanese dwarfing genes is largely unknown. Here, we report a study of WMS261 allelic diversity in a historical wheat collection from 1865 representing worldwide major wheats at the time. The majority carried the previously reported 164 bp or 174 bp allele, but with little geographical correlation. In a few lines, a rare 182 bp fragment was found. Although straw length was recognized as an important character already in the 19th century, Rht8 probably played a minor role for height variation. The use of WMS261 and other functional markers for analyses of historical specimens and characterization of historic crop traits is discussed.
|
|
| 3. |
- Asplund, Linnea, et al.
(författare)
-
Re-evaluating the history of the wheat domestication gene NAM-B1 using historical plant material
- 2010
-
Ingår i: JOURNAL OF ARCHAEOLOGICAL SCIENCE. - : Elsevier Science B.V., Amsterdam. - 0305-4403 .- 1095-9238. ; 37:9, s. 2303-2307
-
Tidskriftsartikel (refereegranskat)abstract
- The development of agriculture is closely associated with the domestication of wheat, one of the earliest crop species. During domestication key genes underlying traits important to Neolithic agriculture were targeted by selection. One gene believed to be such a domestication gene is NAM-B1, affecting both nutritional quality and yield but with opposite effects. A null mutation, first arisen in emmer wheat, decreases the nutritional quality but delays maturity and increases grain size; previously the ancestral allele was believed lost during the domestication of durum and bread wheat by indirect selection for larger grain. By genotyping 63 historical seed samples originating from the 1862 International Exhibition in London, we found that the ancestral allele was present in two spelt wheat and two bread wheat cultivars widely cultivated at the time. This suggests that fixation of the mutated allele of NAM-B1 in bread wheat, if at all, occurred during modern crop improvement rather than during domestication. We also discuss the value of using archaeological and historical plant material to further the understanding of the development of agriculture.
|
|
| 4. |
- Asplund, Linnea, et al.
(författare)
-
Swedish Spring Wheat Varieties with the Rare High Grain Protein Allele of NAM-B1 Differ in Leaf Senescence and Grain Mineral Content
- 2013
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 8
-
Tidskriftsartikel (refereegranskat)abstract
- Some Swedish spring wheat varieties have recently been shown to carry a rare wildtype (wt) allele of the gene NAM-B1, known to affect leaf senescence and nutrient retranslocation to the grain. The wt allele is believed to increase grain protein concentration and has attracted interest from breeders since it could contribute to higher grain quality and more nitrogen-efficient varieties. This study investigated whether Swedish varieties with the wt allele differ from varieties with one of the more common, non-functional alleles in order to examine the effect of the gene in a wide genetic background, and possibly explain why the allele has been retained in Swedish varieties. Forty varieties of spring wheat differing in NAM-B1 allele type were cultivated under controlled conditions. Senescence was monitored and grains were harvested and analyzed for mineral nutrient concentration. Varieties with the wt allele reached anthesis earlier and completed senescence faster than varieties with the non-functional allele. The wt varieties also had more ears, lighter grains and higher yields of P and K. Contrary to previous information on effects of the wt allele, our wt varieties did not have increased grain N concentration or grain N yield. In addition, temporal studies showed that straw length has decreased but grain N yield has remained unaffected over a century of Swedish spring wheat breeding. The faster development of wt varieties supports the hypothesis of NAM-B1 being preserved in Fennoscandia, with its short growing season, because of accelerated development conferred by the NAM-B1 wt allele. Although the possible effects of other gene actions were impossible to distinguish, the genetic resource of Fennoscandian spring wheats with the wt NAM-B1 allele is interesting to investigate further for breeding purposes.
|
|
| 5. |
- Beck, Lisa J., et al.
(författare)
-
Differing Mechanisms of New Particle Formation at Two Arctic Sites
- 2021
-
Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 48:4
-
Tidskriftsartikel (refereegranskat)abstract
- New particle formation in the Arctic atmosphere is an important source of aerosol particles. Understanding the processes of Arctic secondary aerosol formation is crucial due to their significant impact on cloud properties and therefore Arctic amplification. We observed the molecular formation of new particles from low-volatility vapors at two Arctic sites with differing surroundings. In Svalbard, sulfuric acid (SA) and methane sulfonic acid (MSA) contribute to the formation of secondary aerosol and to some extent to cloud condensation nuclei (CCN). This occurs via ion-induced nucleation of SA and NH3 and subsequent growth by mainly SA and MSA condensation during springtime and highly oxygenated organic molecules during summertime. By contrast, in an ice-covered region around Villum, we observed new particle formation driven by iodic acid but its concentration was insufficient to grow nucleated particles to CCN sizes. Our results provide new insight about sources and precursors of Arctic secondary aerosol particles.
|
|
| 6. |
|
|
| 7. |
- Carlson-Nilsson, Ulrika, et al.
(författare)
-
Trait Expression and Environmental Responses of Pea (Pisum sativum L.) Genetic Resources Targeting Cultivation in the Arctic
- 2021
-
Ingår i: Frontiers in Plant Science. - : Frontiers Media SA. - 1664-462X. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- In the Arctic part of the Nordic region, cultivated crops need to specifically adapt to adverse and extreme climate conditions, such as low temperatures, long days, and a short growing season. Under the projected climate change scenarios, higher temperatures and an earlier spring thaw will gradually allow the cultivation of plants that could not be previously cultivated there. For millennia, Pea (Pisum sativum L.) has been a major cultivated protein plant in Nordic countries but is currently limited to the southern parts of the region. However, response and adaptation to the Arctic day length/light spectrum and temperatures are essential for the productivity of the pea germplasm and need to be better understood. This study investigated these factors and identified suitable pea genetic resources for future cultivation and breeding in the Arctic region. Fifty gene bank accessions of peas with a Nordic landrace or cultivar origin were evaluated in 2-year field trials at four Nordic locations in Denmark, Finland, Sweden, and Norway (55 degrees to 69 degrees N). The contrasting environmental conditions of the trial sites revealed differences in expression of phenological, morphological, crop productivity, and quality traits in the accessions. The data showed that light conditions related to a very long photoperiod partly compensated for the lack of accumulated temperature in the far north. A critical factor for cultivation in the Arctic is the use of cultivars with rapid flowering and maturation times combined with early sowing. At the most extreme site (69 degrees N), no accession reached full maturation. Nonetheless several accessions, predominantly landraces of a northern origin, reached a green harvest state. All the cultivars reached full maturation at the sub-Arctic latitude in northern Sweden (63 degrees N) when plants were established early in the season. Seed yield correlated positively with seed number and aboveground biomass, but negatively with flowering time. A high yield potential and protein concentration of dry seed were found in many garden types of pea, confirming their breeding potential for yield. Overall, the results indicated that pea genetic resources are available for breeding or immediate cultivation, thus aiding in the northward expansion of pea cultivation. Predicted climate changes would support this expansion.
|
|
| 8. |
- Forsberg, Nils, et al.
(författare)
-
Farmers without borders-genetic structuring in century old barley (Hordeum vulgare)
- 2015
-
Ingår i: Heredity. - : Nature Publishing Group. - 0018-067X .- 1365-2540. ; 114:2, s. 195-206
-
Tidskriftsartikel (refereegranskat)abstract
- The geographic distribution of genetic diversity can reveal the evolutionary history of a species. For crop plants, phylogeographic patterns also indicate how seed has been exchanged and spread in agrarian communities. Such patterns are, however, easily blurred by the intense seed trade, plant improvement and even genebank conservation during the twentieth century, and discerning fine-scale phylogeographic patterns is thus particularly challenging. Using historical crop specimens, these problems are circumvented and we show here how high-throughput genotyping of historical nineteenth century crop specimens can reveal detailed geographic population structure. Thirty-one historical and nine extant accessions of North European landrace barley (Hordeum vulgare L.), in total 231 individuals, were genotyped on a 384 single nucleotide polymorphism assay. The historical material shows constant high levels of within-accession diversity, whereas the extant accessions show more varying levels of diversity and a higher degree of total genotype sharing. Structure, discriminant analysis of principal components and principal component analysis cluster the accessions in latitudinal groups across country borders in Finland, Norway and Sweden. FST statistics indicate strong differentiation between accessions from southern Fennoscandia and accessions from central or northern Fennoscandia, and less differentiation between central and northern accessions. These findings are discussed in the context of contrasting historical records on intense within-country south to north seed movement. Our results suggest that although seeds were traded long distances, long-term cultivation has instead been of locally available, possibly better adapted, genotypes.
|
|
| 9. |
- Forsberg, Nils, 1981-, et al.
(författare)
-
Population structure in landrace barley (Hordeum vulgare L.) during the late 19th century crop failures in Fennoscandia
- 2019
-
Ingår i: Heredity. - : Springer Science and Business Media LLC. - 0018-067X .- 1365-2540. ; 123:6, s. 733-745
-
Tidskriftsartikel (refereegranskat)abstract
- Agricultural disasters and the subsequent need for supply of relief seed can be expected to influence the genetic composition of crop plant populations. The consequences of disasters and seed relief have, however, rarely been studied since specimens sampled before the events are seldomly available. A series of crop failures struck northern Fennoscandia (Norway, Sweden and Finland) during the second half of the 19th century. In order to assess population genetic dynamics of landrace barley (Hordeum vulgare), and consequences of crop failure and possible seed relief during this time period, we genotyped seeds from 16 historical accessions originating from two time periods spanning the period of repeated crop failure. Reliable identification of genetic structuring is highly dependent on sampling regimes and detecting fine-scale geographic or temporal differentiation requires large sample sizes. The robustness of the results under different sampling regimes was evaluated by analyzing subsets of the data and an artificially pooled dataset. The results led to the conclusion that six individuals per accession were insufficient for reliable detection of the observed genetic structure. We found that population structure among the data was best explained by collection year of accessions, rather than geographic origin. The correlation with collection year indicated a change in genetic composition of landrace barley in the area after repeated crop failures, likely a consequence of introgression of relief seed in local populations. Identical genotypes were found to be shared among some accessions, suggesting founder effects and local seed exchange along known routes for trade and cultural exchange.
|
|
| 10. |
- Hagenblad, Jenny, Associate Professor, 1974-, et al.
(författare)
-
Chevalier barley : The influence of a world-leading malting variety
- 2022
-
Ingår i: Crop science. - : Wiley. - 0011-183X .- 1435-0653. ; 62:1, s. 235-246
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
