Forskningssamarbeid om økokorn

Et europeisk nettverk arbeider med å finne kriterier for hvordan kornsorter som passer i ekstensivt og økologisk landbruk skal foredles. Denne artikkelen viser litt av aktivitetene i nettverket, som har flere norske deltakere

Fusarium spp.

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Replicative aging is associated with loss of genetic heterogeneity from extrachromosomal circular DNA in <i>Saccharomyces cerevisiae</i>

© The Author(s) 2020. Published by Oxford University Press on behalf of Nucleic Acids Research. Circular DNA can arise from all parts of eukaryotic chromosomes. In yeast, circular ribosomal DNA (rDNA) accumulates dramatically as cells age, however little is known about the accumulation of other chromosome-derived circles or the contribution of such circles to genetic variation in aged cells. We profiled circular DNA in Saccharomyces cerevisiae populations sampled when young and after extensive aging. Young cells possessed highly diverse circular DNA populations but 94% of the circular DNA were lost after ∼15 divisions, whereas rDNA circles underwent massive accumulation to >95% of circular DNA. Circles present in both young and old cells were characterized by replication origins including circles from unique regions of the genome and repetitive regions: rDNA and telomeric Y' regions. We further observed that circles can have flexible inheritance patterns: [HXT6/7circle] normally segregates to mother cells but in low glucose is present in up to 50% of cells, the majority of which must have inherited this circle from their mother. Interestingly, [HXT6/7circle] cells are eventually replaced by cells carrying stable chromosomal HXT6 HXT6/7 HXT7 amplifications, suggesting circular DNAs are intermediates in chromosomal amplifications. In conclusion, the heterogeneity of circular DNA offers flexibility in adaptation, but this heterogeneity is remarkably diminished with age.ISSN:1362-4962ISSN:0301-561

Funn av soppmiddelresistent Botrytis i åkerbønne

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Computed Tomography as a Method for Age Determination of Carnivora and Odontocetes with Validation from Individuals with Known Age

Traditional methods for age determination of wildlife include either slicing thin sections off or grinding a tooth, both of which are laborious and invasive. Especially when it comes to ancient and valuable museum samples of rare or extinct species, non-invasive methods are preferable. In this study, X-ray micro-computed tomography (µ-CT) was verified as an alternative non-invasive method for age determination of three species within the order of Carnivora and suborders Odontoceti. Teeth from 13 red foxes (Vulpes vulpes), 2 American mink (Neogale vison), and 2 harbor porpoises (Phocoena phocoena) of known age were studied using µ-CT. The number of visible dental growth layers in the µ-CT were highly correlated with true age for all three species (R2 = 96%, p &lt; 0.001). In addition, the Bland–Altman plot showed high agreement between the age of individuals and visible dental layers represented in 2D slices of the 3D µ-CT images. The true age of individuals was on average 0.3 (±0.6 SD) years higher than the age interpreted by the µ-CT image, and there was a 95% agreement between the true age and the age interpreted from visible dental layers in the µ-CT.</p