Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2009
Sammendrag
In a four year project (2008-2011) the potential will be examined for commercial production of the European blueberry (V. myrtillus ) inNorway, with most effort investigating semi-cultivation practices on forestland. However, adaption to growth on agricultural land will alsobe in focus as well as selecting superior clones adapted to Norwegian regions, and development of effective propagation methods. Also, it isgiven priority to find how the European blueberry (EB) react to climatic parameters, which will be examined under controlled experimentsand paralleled by meteorological data from forest fields.
Forfattere
Rolf NestbySammendrag
Konklusjon.Innvik: Både Agromarin og Marihøne+ gir god avling. Ingen forskjell på gjødselmengder. Ingen positiv virkning av dryppgjødsling. Brønnøysund: Både Agromarin og Marihøne gir god avling.Samspill drypp og fastgjødsel i 2009: Dryppgjødsel + fastgjødsel var positivt i 2009. Harstad: Økt mengde fastgjødsel ga større avling. Agromarin er dårligere enn Marihøne+: K-effekt? Dryppgjødsel + fastgjødsel ga større avling
Forfattere
Mekjell Meland Eva BirkenSammendrag
The European plum cultivar ‘Jubileum" blossoms abundantly most years and too many flowers can be set if not properly thinned. For two seasons started in 2007 mature ‘Jubileum/St. Julien A were treated with ethephon when full bloom opened at concentration of 250, 375 and 500 ppm and at 10-12 mm fruitlets stage at concentration of 125, 250 and 375 ppm. The experimental design was completely randomised with 6 replications of single trees. The trees were sprayed to run-off with a hand sprayer when temperature was above 15 ºC. All thinning treatments reduced the fruit set significantly. The fruit set decreased with increasing ethephon concentration, and the highest rates at bloom and fruitlet overthinned. Less dosage of ethephon was required at fruitlet time in order to obtain the same fruit set. The yield did confirm the fruit set response and the yield reductions were significant. All thinning treatments gave higher percentage of fruits larger than 38 mm fruit size compared to the unthinned control. Fruit quality characterized by blue surface cover and the content of soluble solids was in general high and increased significantly by reduced fruit. Fruit firmness, however, slightly declined in the ethephon thinned trees. Other fruit quality parameter like percentage acid content did not show a clear response to the thinning. Return bloom was little improved on thinned trees the following year. The crop load per tree was reduced to about the half of the previous year control trees included. In conclusion, ethephon application at a rate of 375 ppm applied at full bloom or 250 ppm at 10 mm fruit diameter thinned ‘Jubileum" plums to a target of about 10 -15 % fruit set.
Forfattere
Eivind UlebergSammendrag
QTL mapping experiments aim to find the genes or mutations that contribute to phenotypic variance. This knowledge is important for biological understanding and can be utilized, e.g. for medical or breeding purposes. QTL mapping methods can be categorised as linkage analysis (LA) methods, linkage disequilibrium (LD) based methods and methods combining linkage and linkage disequilibrium analysis (LLD). The basic difference between LA and LD analysis is the calculations of the probability that two animals carry genes that are identical-by-descent (IBD) at a given point on the chromosome. LA is based on within family IBD, whereas LD is based on population-wide IBD probabilities. LA analysis is dependent on recombinations that can be observed in the genotyped data, which limits the accuracy. LD is based on historical recombinations and can find short confidence intervals, but is likely to result in false positives due to spurious associations between markers and QTL. To avoid the problems of separate LA or LD analysis, approaches combining linkage and linkage disequilibrium mapping (LLD) have been proposed. The main objective of this thesis has been to make maximum use of genotyping information from QTL mapping experiments for detecting as many as possible QTL and position them as precisely as possible. Specific issues addressed have been single versus multiple mapping methods (paper 1), the effects of including the causative mutation amongst the markers in QTL mapping experiments (paper 2) and developing a statistical test to distinguish causative from non-causative SNPs (paper 3).In paper 1 single and multi QTL fine-mapping methods were compared in a situation where two QTL were located in the analysed region. The single QTL method had problems differentiating between two QTLs when these were closely located, which often resulted in discovery of a ghost QTL between the real ones, or no clear QTL discovery. The multi QTL approach found evidence of both QTLs even when these were close (15cM). Although these differences to some extent may be explained by the different statistical approaches used by the two methods, the main conclusion from this paper is that multi QTL mapping methods should be applied when analysing QTL data. Paper 2 investigated the effect of including the causative SNP amongst the markers in a QTL mapping experiment. Both power and precision was greatly increased by including the causative mutation. When the causative mutation was not included amongst the markers the LLD method had clearly better precision and power than the association method. The increased power from including the causative SNP as marker was larger with association mapping than LLD mapping, and when the causation was included amongst the markers the methods had similar power and precision. These differences were partly due to the test-statistics, as the association method tested directly on the markers, while the LLD method tested the midpoints of the marker brackets. Including the causative mutation as marker increases the possibility of discovering QTLs of smaller effects.The increased power and precision obtained by including the causative SNP amongst the markers, was in paper 3 used to develop a test to confirm causative SNPs. The ‘Causative SNP Test" obtained a power of 28 % in this study, while the power of QTL detection was 97 %. The low power of CST was due to strong LD between the analyzed markers. All confirmed SNPs were truly causative and correctly positioned by the CST test. Thus, if positive, this test provides a lot of evidence for causality.Results from QTL mapping experiments so far indicates that most complex traits are controlled by many genes, with mainly small effects on variance. Currently available genome sequences and sample sizes has limited power to detect QTLs with small effects and thus, reported QTLs so far only explains small proportions of observed phenotypic variance for most traits. Future prospects of complete genome sequences will increase the power to find QTLs. The recent strong focus on genome-wide association studies (GWAS) will be expected also for future experiments. This study has shown that future QTL mapping experiments should use multi QTL approaches, to avoid bias from additional QTLs. As the power of QTL mapping is greatly increased by including the causative mutation amongst the markers, one should also aim to design experiments that have high power to distinguish causative from non-causative mutations. Experiments where the relationship between the individuals is low, as is generally the case in human GWAS studies, seem to achieve this. The causality can in the next step be tested by the proposed CST test.
Forfattere
Gunhild Børtnes Ruth MordalSammendrag
Det er ikke registrert sammendrag
Forfattere
Mekjell MelandSammendrag
The performance of 26 different cherry rootstocks (‘Hexaploid Colt"," Damil", ‘Tabel® Edabriz", ‘Gisela® (Gi) 3", ‘4", ‘5", ‘6", ‘7", ‘11", ‘Giessen (GI) 107/1", ‘148/13", ‘154/7" , ‘195/20", ‘318/17", ‘497/8", ‘523/02", ‘Weiroot (W) 10", ‘53", ‘158", ‘Maxma 14", ‘Maxma 60", ‘Maxma 97", ‘PHL-A", ‘PHL-B", ‘Piku®1"and ‘Piku® 3"), compared with ‘Colt" as a standard, for the cultivar ‘Lapins" (Prunus avium L), was assessed in a field trial in western Norway at 60° North. Trees, one-year-old whips, were planted in spring 1999; at 2.0 x 4.5 m spacing and trained to central leader as free spindle. Tree vigour, yield, fruit size, fruit quality and yield efficiency were evaluated for eight subsequent years. Tree sizes were significantly affected by the rootstocks after eight years growth. ‘Tabel®Edabriz", ‘Gi 3" and ‘Gi 4" produced the smallest and ‘Piku®3", ‘Colt"," Damil" and ‘Maxma 60" the largest trees as measured by trunk cross-sectional area (TCSA). The most vigourus rootstock had five times larger TCSA than the dwarfest rootstocks. ‘Piku®1" was the most productive rootstock for this cultivar with highest cumulative yield followed by ‘Colt", ‘Piku®3" and ‘Gi 523/02". Average yield per tree and per year during the first seven cropping years was 12 kg for ‘Piku®1". ‘Piku®1" and ‘Gi 5" induced early bearing. Trees on ‘Gi 5" and ‘Gi 6"were the most yield efficient. Fruit size became significantly affected by the different rootstocks. In average for the different cropping years many of the Gi number selections, ‘Colt", ‘Damil" and ‘Piku®1"all had a average fruit weight larger than 10 g per fruit. Fruit quality characterized by the content of soluble solids was in an average of 17.5 %. It was not influenced by crop load and did not differ much between trees on the various rootstocks. In conclusion, for high density production systems the most productive semi-vigorous rootstocks were ‘Colt"," Piku®3" and ‘Damil" and the semi-dwarf Piku®1", ‘Gi 5" and "Gi 6".
Forfattere
C. Kaiser J.M. Christensen l. Long I. Hanrahan Mekjell Meland E. FallahiSammendrag
Rain-induced fruit cracking in sweet cherries can be a major problem. In the Pacific Northwest, due to high labor costs, when fruit cracking exceeds 25% at harvest, fruit are not picked. OSU Horticulture and Pharmacy Faculty have collaborated in producing and patenting a novel, elastic, organic biofilm, SureSeal, which significantly reduced sweet cherry fruit cracking by up to 250% in Milton Freewater, Oregon and Loftus, Norway. Formulations of SureSeal are hydrophobic and consists of a copolymer of complex carbohydrates, phospholipids and calcium. Collaborative research undertaken over three years throughout the Pacific Northwest and overseas found that two applications of 1% SureSeal applied at straw color and again ten days later, reduced fruit cracking consistently when compared to untreated control fruit. Indeed, in Norway, fruit cracking was reduced from 24.6% to 9.8% when trees were treated with SureSeal in combination with plastic ground covers and a preharvest fungicide (fenhexamid). Furthermore, all these studies throughout Oregon and Idaho, found that SureSeal resulted in significantly (P
Forfattere
Gunhild Børtnes Ruth MordalSammendrag
Tyrkermynte (Dracocephalum moldavicum) er ein eittårig vekst som vert 30-60 cm høg. Den har vore mykje brukt i folkemedisinen der den kjem frå i Sør-Sibir og Himaleya. Aromaen minner om sitronmelisse og kan brukast som denne i salatar og i fiskerettar. Tyrkermynte er også ein vakker prydplante som med fordel også kan takast i bruk i Norge.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Vibeke Lind Jan Berg Lars Olav Eik Svein Eilertsen Jørgen A.B. Mølmann Margrethe Hersleth Nils Kristian Afseth Espen HauglandSammendrag
With the objective of studying the effects of production systems on meat quality, 75 Norwegian White Sheep lambs were subjected to one of the following treatments: continuous grazing on a semi-natural lowland pasture until slaughtering (Control); continuous grazing followed by either stall-feeding on concentrate and grass silage or grazing ryegrass pasture for 44 or 24 days before slaughtering (Conc44, Conc24, Rye44, Rye24). Loin samples of M. longissimus dorsi including the subcutaneous fat were analysed for sensory attributes and fatty acid composition. Compared with the control group, a lower intensity of acid taste (P<0.05) and a lower content of C18:3n-6 fatty acids (P<0.001) were observed in the Conc44 group. The n-6/n-3 ratio was higher (P<0.001) in meat tested from the concentrate treatments compared to the ryegrass treatments. These findings indicate that the fattening of lambs on improved pastures or a concentrate-based diet prior to slaughter may alter meat characteristics.