1,721,004 research outputs found
Genredigering av bringebær (Rubus ideaeus L.) ved hjelp av CPISPR/Cas9 utslag av genet F3'H
No full textBreeding new improved crop varieties is a lengthy process that can take many years. With climate change and more rapidly changing environmental conditions, it becomes even more important to develop new varieties quickly. Gene editing presents a useful tool to achieve this. The relatively new gene editing method CRISPR/Cas9 is simple, cost-effective and above all more precise than most other methods. Due to its novelty there is no protocol for CRISPR/Cas9 for many plants. The aim of this thesis is to develop such a protocol for rasp-berry which is an economically important crop, especially in the northern parts of Europe. As a proof of concept, the gene F3’H, an important gene for synthesis of the main anthocyanin cyanidin in the berries of raspberry, was knocked out.
Several different delivery methods for CRISPR/Cas9 have been used in this thesis. Two types of Agrobacterium-mediated transformation have been tested: transformation of in-vitro ex-plants to regenerate entire transformed pants and agroinfiltration of greenhouse-grown plants as a quick method to test the designed CRISPR/Cas9 constructs. Biolistic transformation by gold particle bombardment of callus was also tested. The focus however was on obtaining transformed plants by Agrobacterium-mediated transformation, by far most the common transformation method for plants.
Plants were regenerated only after the Agrobacterium-mediated transformation. These plants were likely transformed, but the plants were too small to verify this through a PCR screening when the experiment had to end due to the submission date for this thesis. It turned out that agroinfiltration, as it is used for tobacco, is not a suitable transformation method for raspberry. Neither were any plants regenerated from the bombarded callus. However, it could be verified that there were changes in the genome of some callus cells within the target region of the CRISPR/Cas9 constructs.GraminorM-P
Evaluation of Detached Leaflet Assay as a High-Throughput Way to Select for Late Blight Resistant Potato
Get PDFThe potato (Solanum tuberosum) is the world’s third most important food crop. It is grown all over the world. Late blight is an important disease in potato, caused by the pathogen Phytophthora infestans. The disease causes large crop losses and infects both the foliage and tubers, if not controlled by fungicide application. Developing new potato cultivars with improved resistance against late blight, is important in breeding programs, as these would allow less frequent spraying and a more sustainable potato production. Resistance against foliage late blight is usually evaluated in large scale field trials. Such trials are often expensive, difficult to manage and control. Alternative ways of assessing resistance that is cost-effective, high-throughput and precise are therefore of great interest.
The purpose of this thesis is to investigate whether a detached leaflet assay (DLA) can be used to detect resistance against foliage late blight in different potato genotypes. This was investigated through assessment of 255 cultivars and breeding material (genotypes) representing the Norwegian germplasm. One plant per genotype was grown in pots in a greenhouse. After 8 weeks, leaves were detached and 9 leaflets per genotype were placed in Petri dishes and inoculated with P. infestans. The infection was assessed visually and by image analysis 6 and 8 days after inoculation. The results were compared with historical field data, and a genome-wide association study was performed.
The results showed that the leaf test was able to distinguish potato genotypes based on their susceptibility to late blight. There was a low frequency of infection on the leaflets. A reason for this may be that the inoculum had reduced infectivity due to age. The correlation between the DLA and the historical field data was limited, but significant. The leaf test was able to identify the potato genotypes most susceptible to late blight. The association study found several significant markers. A marker found on chromosome 3, was located near a known QTL for late blight resistance.
It can be concluded that the DLA can be used to identify the genotypes that are most susceptible to foliage late blight before an eventual field trial
Gene editing of red raspberry (Rubus idaeus L.) with CRISPR/Cas9 knocking out F3'H
No full textBreeding new improved crop varieties is a lengthy process that can take many years. With climate change and more rapidly changing environmental conditions, it becomes even more important to develop new varieties quickly. Gene editing presents a useful tool to achieve this. The relatively new gene editing method CRISPR/Cas9 is simple, cost-effective and above all more precise than most other methods. Due to its novelty there is no protocol for CRISPR/Cas9 for many plants. The aim of this thesis is to develop such a protocol for rasp-berry which is an economically important crop, especially in the northern parts of Europe. As a proof of concept, the gene F3’H, an important gene for synthesis of the main anthocyanin cyanidin in the berries of raspberry, was knocked out.
Several different delivery methods for CRISPR/Cas9 have been used in this thesis. Two types of Agrobacterium-mediated transformation have been tested: transformation of in-vitro ex-plants to regenerate entire transformed pants and agroinfiltration of greenhouse-grown plants as a quick method to test the designed CRISPR/Cas9 constructs. Biolistic transformation by gold particle bombardment of callus was also tested. The focus however was on obtaining transformed plants by Agrobacterium-mediated transformation, by far most the common transformation method for plants.
Plants were regenerated only after the Agrobacterium-mediated transformation. These plants were likely transformed, but the plants were too small to verify this through a PCR screening when the experiment had to end due to the submission date for this thesis. It turned out that agroinfiltration, as it is used for tobacco, is not a suitable transformation method for raspberry. Neither were any plants regenerated from the bombarded callus. However, it could be verified that there were changes in the genome of some callus cells within the target region of the CRISPR/Cas9 constructs
Detection and validation of disease resistance QTL in wheat
No full textPowdery mildew (PM), Fusarium head blight (FHB) and Septoria leaf blotch (SNB) are devastating wheat diseases. Breeding of disease resistant varieties is an economical and environmentally friendly approach and is given high priority in the Norwegian wheat breeding program at Graminor Breeding AS.
Resistance breeding is a challenging task. For some diseases, major resistance genes have been detected and utilised in breeding, but when commercial varieties carrying major genes are grown in large areas, the resistance can be overcome by the pathogen after a few years of cultivation. For these diseases, the search and utilisation of quantitative resistance genes is a more durable solution. For other diseases, the resistance mechanisms have been found to be mainly polygenic and quantitative. Utilisation of quantitative resistance genes, and combining several of these quantitative loci, is a solution for breeding of more resistance varieties against these diseases.
In this study, two SNP Chips were utilised; the Illumina 90K SNP Chip and the Affymetrix 35K SNP Chip. The recombinant inbred line (RIL) populations Shangahi3/Catbird (SHA3/CBRD) x Naxos and Soru#1 x Naxos, and a spring wheat association mapping panel consisting of 123 lines were genotyped with the Illumina 90K SNP Chip. An association mapping panel consisting of 299 spring wheat lines and RIL population Soru#1 x Naxos were genotyped with the Affymetrix 35K SNP Chip.
For the SHA3/CBRD x Naxos population, linkage maps containing both SNP, SSR and DArT markers were developed. For the Soru#1xNaxos population, two sets of linkage maps were developed; one set with Illumina 90K SNP markers and SSR markers, and a second set contained Illumina 90K and Affymetrix SNP markers in addition to SSR markers.
In paper I, we utilised the two RIL populations, SHA3/CBRD x Naxos and Soru#1 x Naxos, that both segregate for PM. These RIL populations had been evaluated for PM in several environments in Norway and China. The previous QTL mapping study had detected a major QTL for PM resistance on chromosome 1AS contributed by Naxos. That study was performed with SSR and DArT markers. With the saturation of the SHA3/CBRD x Naxos map with SNP markers and the SNP genotyping of Soru#1 x Naxos we could more precisely map and validate this 1AS QTL. Further work is now in progress to fine-map this 1AS QTL.
Paper II focused on SNB. We used the RIL population SHA3/CBRD which segregates for SNB. This population had previously been evaluated for adult plant resistance to SNB in field trials. Seedling resistance were tested in the greenhouse with inoculation of P. nodorum isolates and infiltrations with isolates and necrotrophic effectors. With the use of a more saturated marker map in the SHA3/CBRD x Naxos population we could map the Snn3 locus on chromosome 5BS in SHA3/CBRD and detect QTL for sensitivity to SnTox3 in this locus both in adult plants and in seedlings.
In paper III, we utilised the 299 association mapping panel genotyped with the Affymetrix 35K SNP Chip. FHB was evaluated in several environments in spawn inoculated fields, and DON measurements was performed by GC-MC. Anther extrusion (AE), plant height (PH) and days to heading (DH) of the lines in the collection were also evaluated in field trials. Eight QTL were detected that were significant in three or more testing environments consistent for both FHB and DON. Of these eight QTL, seven coincided with AE. Evaluation of the mapping panel displayed a clear positive effect on resistance when combining several resistance alleles. The results also provided an overview of which of the detected QTL were present in different lines in the mapping panel and which QTL was less and more utilised in the different parts of the wheat collection
Deteksjon og validering av QTL for sykdomsresistens i hvete
Get PDFPowdery mildew (PM), Fusarium head blight (FHB) and Septoria leaf blotch (SNB) are devastating wheat diseases. Breeding of disease resistant varieties is an economical and environmentally friendly approach and is given high priority in the Norwegian wheat breeding program at Graminor Breeding AS.
Resistance breeding is a challenging task. For some diseases, major resistance genes have been detected and utilised in breeding, but when commercial varieties carrying major genes are grown in large areas, the resistance can be overcome by the pathogen after a few years of cultivation. For these diseases, the search and utilisation of quantitative resistance genes is a more durable solution. For other diseases, the resistance mechanisms have been found to be mainly polygenic and quantitative. Utilisation of quantitative resistance genes, and combining several of these quantitative loci, is a solution for breeding of more resistance varieties against these diseases.
In this study, two SNP Chips were utilised; the Illumina 90K SNP Chip and the Affymetrix 35K SNP Chip. The recombinant inbred line (RIL) populations Shangahi3/Catbird (SHA3/CBRD) x Naxos and Soru#1 x Naxos, and a spring wheat association mapping panel consisting of 123 lines were genotyped with the Illumina 90K SNP Chip. An association mapping panel consisting of 299 spring wheat lines and RIL population Soru#1 x Naxos were genotyped with the Affymetrix 35K SNP Chip.
For the SHA3/CBRD x Naxos population, linkage maps containing both SNP, SSR and DArT markers were developed. For the Soru#1xNaxos population, two sets of linkage maps were developed; one set with Illumina 90K SNP markers and SSR markers, and a second set contained Illumina 90K and Affymetrix SNP markers in addition to SSR markers.
In paper I, we utilised the two RIL populations, SHA3/CBRD x Naxos and Soru#1 x Naxos, that both segregate for PM. These RIL populations had been evaluated for PM in several environments in Norway and China. The previous QTL mapping study had detected a major QTL for PM resistance on chromosome 1AS contributed by Naxos. That study was performed with SSR and DArT markers. With the saturation of the SHA3/CBRD x Naxos map with SNP markers and the SNP genotyping of Soru#1 x Naxos we could more precisely map and validate this 1AS QTL. Further work is now in progress to fine-map this 1AS QTL.
Paper II focused on SNB. We used the RIL population SHA3/CBRD which segregates for SNB. This population had previously been evaluated for adult plant resistance to SNB in field trials. Seedling resistance were tested in the greenhouse with inoculation of P. nodorum isolates and infiltrations with isolates and necrotrophic effectors. With the use of a more saturated marker map in the SHA3/CBRD x Naxos population we could map the Snn3 locus on chromosome 5BS in SHA3/CBRD and detect QTL for sensitivity to SnTox3 in this locus both in adult plants and in seedlings.
In paper III, we utilised the 299 association mapping panel genotyped with the Affymetrix 35K SNP Chip. FHB was evaluated in several environments in spawn inoculated fields, and DON measurements was performed by GC-MC. Anther extrusion (AE), plant height (PH) and days to heading (DH) of the lines in the collection were also evaluated in field trials. Eight QTL were detected that were significant in three or more testing environments consistent for both FHB and DON. Of these eight QTL, seven coincided with AE. Evaluation of the mapping panel displayed a clear positive effect on resistance when combining several resistance alleles. The results also provided an overview of which of the detected QTL were present in different lines in the mapping panel and which QTL was less and more utilised in the different parts of the wheat collection.Meldugg (PM), Fusarium head blight (FHB) og hveteaksprikk (SNB) er svært skadelige sykdommer i hvete. Å foredle hvetesorter med resistens mot disse sykdommene er en økonomisk og miljøvennlig tilnærming, og er gitt høy prioritet i det norske hveteforedlingsprogrammet ved Graminor AS.
Å foredle sykdomsresistente sorter er utfordrende. For noen sykdommer har enkelte hovedgener blitt oppdaget og brukt i utviklingen av nye sorter. Når en sort med kun enkelt-gener mot en sykdom dyrkes kommersielt på store arealer blir denne resistensen ofte raskt brutt ned pga endring i patogenpopulasjonen. For slike sykdommer er det en bedre strategi å lete etter, og utnytte, flere gener med mindre resistens effekt enn hovedgenene som samlet vil kunne gi en god og mere varig resistens. For andre typer sykdommer er det ikke funnet hovedresistensgener, men kun gener med lavere grad av resistens enn hovedgenene og polygene resistensmekanismer hvor mange gener med liten grad av resistens samlet sett gir mer eller mindre resistente planter.
I dette prosjektet ble to ulike SNP Chiper med sekvenser fra referanse genomsekvensen til IWGSC (International Wheat Genome Sequencing Consortium) brukt; Illumina 90K SNP Chipen og Affymetrix 35K SNP Chipen. De to RIL populasjonene Shanghai3/Catbird (SHA3/CBRD) x Naxos og Soru#1xNaxos, og en assosiasjonskartleggings-kolleksjon bestående av 123 vårhvete- linjer ble genotypet med Illumina 90K SNP Chipen. En assosiasjons-kartleggingskolleksjon bestående av 299 vårhvete-linjer og RIL populasjonen Soru#1 x Naxos ble genotypet med Affymetrix 35K SNP Chipen.
For SHA3/CBRD x Naxos ble det laget koblingskart basert både på SNP, SSR og DArT markører. For Soru#1xNaxos ble det laget to ulike typer koblingskart; èn type koblingskart med Illumina 90K SNP markører og SSR markører, og en annen type med Illumina 90K SNP markører og Affymetrix 35K SNP markører i tillegg til SSR markører.
I paper I ble de to RIL populasjonene SHA3/CBRD x Naxos og Soru#1 x Naxos benyttet. Begge populasjonene spalter for PM, og hadde blitt evaluert for PM i flere miljøer i Norge og Kina. En tidligere QTL kartleggingsstudie hadde detektert et QTL for PM på brødhvetekromosom 1AS fra Naxos. Denne studien var utført med SSR og DArT markører. Med nye koblingskart med mange fler markører både i SHA3/CBRD x Naxos og Soru#1 x Naxos krysningene klarte vi å kartlegge dette 1AS QTLet mer presist og videre validere det. Videre arbeid er nå i gang for å finkartlegge dette 1AS QTLet
Paper II fokuserte på SNB. Vi brukte her RIL populasjonen SHA3/CBRD x Naxos, som spalter for SNB. Denne populasjonen hadde tidligere blitt evaluert for SNB i feltforsøk. Småplante- resistens ble testet i veksthus med inokulering av P. nodorum isolater og infiltrering med isolater og nekrotrofe effektorer. Ved å benytte det nye utviklede koblingskartet av SHA3/CBRD x Naxos med mange markører var det mulig å plassere Snn3 locuset på kromosom 5BS og detektere QTL for mottakelighet til SnTox3 i Snn3 locuset både på voksen- og småplantestadiet.
Paper III benyttet et panel bestående av 299 vårhvete linjer. Dette panelet ble genotypet med Affymetrix 35K SNP Chipen. FHB ble evaluert i flere miljøer i smittefelt og DON nivå ble målt med GC-MS. AE, PH og DH ble også evaluert i de ulike linjene i ulike felt. Åtte QTL ble avdekket som var signifikante i tre eller flere miljøer for både FHB og DON. Av disses åtte, hadde syv sammenfallende posisjon som detekterte QTL for AE. Evaluering av hvetekolleksjonen viste en klar positiv effekt av å kombinere flere av de detekterte QTLene i studien. Resultatene fra studien ga også en oversikt over hvilke linjer i kolleksjonen som inneholdt hvilke av de åtte konsistente QTLene og hvilke QTL som var høyt og lavt utnyttet i de ulike delene av hvetekolleksjonen
Forbedring av frøsettingspotensialet i tetraploid rødkløver (Trifolium pratense L.)
Get PDFTetraploid red clover has similar forage properties as diploid red clover. However, tetraploid red clover plants are taller, have thicker stems, larger leaves and flower heads, and bigger seeds resulting in higher forage yield than diploid red clover plants. However, the seed yield of tetraploids is significantly lower than of diploids, which is challenging for seed companies. For farmers to be able to benefit from higher forage yield of tetraploids, the seed yield of tetraploid red clover has to be improved. In this project, we studied different aspects of seed yield in tetraploid red clover, focusing on seed yield components. In two consecutive years, twelve Norwegian and Swedish cultivars/breeding lines were studied as spaced plants and in dense canopy trials. Trials with spaced plants were established at one locality while the trials with dense canopies were established at four locations (two in Norway and two in Sweden). Seed yield per flower head was identified as the seed yield component most strongly correlated with the seed yield per plant and with the seed yield per area. Additionally, we found that the seed yield was significantly higher in cultivars developed by crossing of existing tetraploids than in neopolyploids. Our study also aimed to identify putative genes that control seed yield in tetraploid red clover. Transcriptomic analysis was performed on flower buds obtained from two relatively high and two low seed yielding plants, with the aim of identifying transcripts that potentially are involved in determination of seed yield. Genes related to flower development, pollen pistil interactions, photosynthesis and embryo development were differentially expressed in the two genotypes contrasting in seed yield. A significant number of genes related to pollination was overrepresented in the high seed yielding genotypes, which might be a reason for their good seed setting ability. The candidate genes detected in this study might be used to develop molecular tools for breeding tetraploid red clover varieties with improved seed yield potentials.Tetraploid rødkløver har samme egenskaper som diploid rødkløver, men den er høyere, har tykkere stengler, større blader, større blomsterhoder og større frø. Som resultat av dette er fôravlingene større sammenlignet med diploid rød kløver. Dessverre gir tetraploid rødkløver betydelig lavere frøavling, noe som byr på utfordringer når frøfirmaene skal produsere frø til sine engfrøblandinger. For at bonden skal fortsette å ha nytte av de gode egenskapene som tetraploid rødkløver har, må frøavlingen forbedres. Vi har studert ulike frøavlingskomponenter som påvirker frøavlspotensialet i tetraploid rødkløver. Målet var å identifisere komponenter som kan benyttes til å øke frøavlingen ved foredling. Tolv norske og svenske sorter/foredlingslinjer ble studert i enkelplanteforsøk og i tett bestand i to påfølgende år. Enkelplanteforsøk ble anlagt på ett sted mens forsøkene i tett bestand ble anlagt på fire steder (to i Norge og to i Sverige). Frøavling per blomsterhode ble identifisert som den frøavlingskomponenten som hadde størst betydning både i enkelplanteforsøk og i tett bestand. I tillegg ble det funnet at tetraploide sorter som var utviklet ved å krysse eksisterende tetraploide planter ga høyere frøavling enn sorter utviklet ved å kromosomfordoble diploider. Et av målene var også å identifisere gener som potensielt påvirker frøavling i tetraploid rødkløver. RNA sekvensering av blomsterknopper fra to planter med relativ høy frøavling og to med relativt lav frøavling hadde som mål å identifisere overuttrykte og underuttrykte transkripter som kunne forklare forskjellene i frøavling mellom disse plantene. Gener relatert til blomster-utvikling, pollen-griffel samspill, fotosyntese og embryo utvikling var forskjellig utrykt i planter med lav og høy frøavling. Et betydelig antall gener relatert til pollinering var overuttrykt i planter med høy frøavling som kan være grunn til dens høy frøavlingsevne. Kandidat gener identifisert i denne studien kan muligens brukes til å utvikle molekylære verktøy for foredling av tetraploid rødkløver med større frøavling
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Havreforedling i den genomiske tidsalder : resistens mot Fusarium
Get PDFIn Norway, oat, along with wheat and barley, constitute one of the three major crops, valued as a break crop due to its minimal disease overlaps with the others. However, a significant threat to the cereal crops, particularly oats, is Fusarium head blight (FHB) disease, caused by the fungal pathogen Fusarium graminearum. FHB negatively impacts yield, quality, and germination ability, and it also generates a mycotoxin called deoxynivalenol (DON), which poses health risks to both humans and animals. The occurrence of Fusarium head blight is promoted by environmental conditions such as continuous precipitation, warm summer, and prolonged harvest periods. Previous outbreaks of this disease have had severe consequences for the oat industry, resulting in reduced grain prices for farmers, diminished high-quality grains for millers and the feed industry, and lower-quality seeds with reduced germination capacity for seed producers.
Developing resistant oat varieties through traditional breeding methods is time-consuming and costly, involving extensive field trials and post-harvest analysis of DON content and germination potential. Recent initiatives aimed at enhancing resistance in Norwegian oat varieties have identified potential sources of resistance and implemented field trials and analysis through the breeding company Graminor, even at a significant cost. Genetic studies have revealed that resistance to Fusarium in oats is a highly quantitative trait influenced by numerous small-effect Quantitative Trait Loci (QTL). This makes it a promising candidate for genomic selection (GS), a DNA-based breeding technique. GS enables breeders to perform selection at earlier stages based on predicted breeding values calculated from statistical models and DNA markers. To effectively implement GS in the Norwegian breeding program, a set of training individuals must be genotyped and accurately phenotyped. This project aimed to introduce genomic selection into the Norwegian breeding program through three tasks. The first task involved evaluating strategies to optimize training populations and resulted in an article published in autumn 2022 which concluded that population size and genetic similarity between training and testing populations was the most important criteria to optimize. Genetic and phenotypic diversity was less important, but still played a vital role as long as the other criteria were optimized. The Prediction core strategy worked best in balancing these optimization criteria and resulted in significantly higher prediction ability than random selection. An optimized training population was sown in mist irrigated and inoculated disease trials in two locations (Staur and Vollebekk) in three years (2020, 2021 and 2023) and analysed for DON content and germination ability. Three validation populations were also analysed in separate years in 2020, 2021 and 2022. Data were used in task 2 and 3. The second task involved conducting genome-wide association mapping to pinpoint crucial regions for FHB resistance in Norwegian germplasm. This research successfully identified 15 different QTL-regions, with five of them consistently validated in breeding material as having a substantial impact. The third task employed phenotypes, whole-genome markers, and the significantly associated QTL-regions from the association mapping to predict the phenotypes of three distinct breeding populations. Using these QTL-regions as fixed effects in GS, the project achieved moderately high accuracy in predicting DON and germination percentages, ranging between 0.44 and 0.47 for DON in the breeding populations. Although the added QTL-regions enhanced accuracy individually and in a cross-validation setup within the training population, their impact varied across different breeding populations.
The results of this thesis will facilitate Graminor's adoption of GS for FHB resistance, reducing breeding costs and enabling screening in earlier generations. Furthermore, it will serve as a foundation for the implementation of GS for other traits, thereby enhancing the overall efficiency of oat breeding.Havre er blant de tre viktigst kornslagene i Norge, og er ansett som god art for vekstskifte med bygg og hvete fordi de har få sykdommer til felles. Men, en sykdom som har potensielt store konsekvenser i alle kornslagene, og spesielt havre, er aksfusariose. Det er en sykdom forårsaket av sekksporesoppen Fusarium graminearum. Den reduserer avling, kvalitet, spireprosent og produserer et giftstoff som heter deoxynivalenol (DON) som er skadelig for både mennesker og dyr. Giftstoffet er strengt regulert i EU og Norge, og i år med store smitteutbrudd kan bøndene få redusert pris på levert korn. I utbruddene mellom 2008-2012 måtte 30% av havrepartiene forkastes på grunn av lav spireevne, og 40% av leverte partier fikk redusert pris på grunn av forhøyede DON verdier. Sammen med jordbearbeiding og god agronomisk praksis er bruk av resistente sorter en av de beste måtene å redusere risikoen for høyt smittepress.
Utviklingen av resistente sorter tar lang tid og koster mye i form av feltforsøk og analyser for DON og spireprosent. Nye forskningsprosjekter satte som mål å finne kilder til resistens og implementere ny kunnskap for å forbedre resistensforedlingen. Disse studiene viste at resistensen i havre er kvantitativ med mange gener som hver for seg gir liten effekt. En foredlingsteknikk som kan tas i bruk for å effektivisere resistensforedlingen er genomisk seleksjon (GS). Dette er en metode som baserer seg på å bruke genetiske og fenotypiske data for en populasjon til å trene en statistisk modell som skal kunne forutsi resistensen til nytt foredlingsmateriale basert på kun genetiske data. Dette vil gjøre det mulig å gjøre seleksjon av materiale i tidlige generasjoner og dermed øke seleksjonsintensiteten for Fusariumresistens. Dette kan også potensielt spare kostnader i feltforsøk og analyser. Målet med dette prosjektet var å implementere genomisk seleksjon i det norske havreforedlingsprogrammet gjennom tre arbeidspakker. I arbeidspakke 1 ble det benyttet en større samling foredlingslinjer og historiske sorter til å evaluere forskjellige strategier for optimalisering av treningspopulasjoner. Dette resulterte i en artikkel som ble publisert i 2022 som konkluderte at de viktigste parameterne å optimalisere var størrelse på populasjonen og den genetiske likheten mellom trenings- og testingspopulasjonen. Genetisk og fenotypisk diversitet spilte mindre viktig rolle, men hadde fortsatt betydning gitt at de andre kriteriene var optimalisert. Det var strategien «Prediction core» som klarte å balansere optimaliseringskriteriene best og strategien resulterte i signifikant høyere treffsikkerhet enn et tilfeldig utvalg. Dette arbeidet resulterte også i en optimalisert treningspopulasjon på 541 genotyper som ble sådd ut i inokulerte Fusarium forsøk med dusjvanning for å gi gode forhold for infeksjon. Forsøkene ble gjennomført med to gjentak, på to steder (Vollebekk og Staur) i tre år (2020, 2021 og 2022). Prøvene ble analysert for DON innhold og spireprosent. Data fra forsøkene ble brukt i arbeidspakke 2 and 3. Arbeidspakke 2 var å gjøre en assosiasjonskartlegging for Fusarium resistens og resulterte i 48 signifikante markører fordelt over 15 områder på genomet. Resistente og mottakelige alleler av disse områdene ble identifisert, hvorav fem ble validert med konsistent effekt over miljø og viste resistens i tre ulike valideringspopulasjoner. Disse resultatene ble brukt i arbeidspakke 3 hvor genomiske prediksjonsmodeller ble brukt som inkluderte effekten av de fem validerte gen områdene, samt resten av resultatene fra assosiasjonskartleggingen for å forutsi DON og spireprosent i de tre valideringspopulasjonene. Resultatet var modeller som gav moderat høy treffsikkerhet mellom 0.44 og 0.47 for DON. Effekten av å bruke informasjonen fra assosiasjons¬kartleggingen varierte med egenskap og populasjoner, med i de fleste tilfellene ble treffsikkerheten høyere eller uforandret. Selv om inkludering av markører fra alle signifikante QTL resulterte i høyere treffsikkerhet i treningspopulasjonen, førte det til lavere treffsikkerhet i valideringspopulasjonene. Resultatene i denne avhandlingen vil gi Graminor muligheten til å implementere genomisk seleksjon for Fusariumresistens i havreforedlingsprogrammet. Arbeidet gir også et fundament for videre utvikling av genomisk seleksjon som seleksjonsmetode i planteforedling.Graminor A
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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