Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2018
Authors
Tatsiana EspevigAbstract
No abstract has been registered
Abstract
Acetophenones are phenolic metabolites of plant species. A metabolic route for the biosynthesis and release of 2 defence‐related hydroxyacetophenones in white spruce (Picea glauca) was recently proposed to involve 3 phases: (a) biosynthesis of the acetophenone aglycons catalysed by a currently unknown set of enzymes, (b) formation and accumulation of the corresponding glycosides catalysed by a glucosyltransferase, and (c) release of the aglycons catalysed by a glucosylhydrolase (PgβGLU‐1). We tested if this biosynthetic model is conserved across Pinaceae and land plant species. We assayed and surveyed the literature and sequence databases for possible patterns of the presence of the acetophenone aglycons piceol and pungenol and their glucosides, as well as sequences and expression of Pgβglu‐1 orthologues. In the Pinaceae, the 3 phases of the biosynthetic model are present and differences in expression of Pgβglu‐1 gene orthologues explain some of the interspecific variation in hydroxyacetophenones. The phylogenetic signal in the metabolite phenotypes was low across species of 6 plant divisions. Putative orthologues of PgβGLU‐1 do not form a monophyletic group in species producing hydroxyacetophenones. The biosynthetic model for acetophenones appears to be conserved across Pinaceae, whereas convergent evolution has led to the production of acetophenone glucosides across land plants.
Abstract
Throughout history, man has strongly utilized and affected forest genetic resources in Europe. From an evolu-tionary perspective deforestation/fragmentation (→genetic drift), transfer of seeds and plants to new environ-ments (→mainly gene flow) and selective logging (→selection) are most relevant and have been particularlyaddressed in this review. In contrast to most conifers, broadleaved tree populations have been especially reducedby historic fragmentation, and consequently, the related genetic effects have been possibly more pronounced.Widespread wind-pollinated species with wind/animal dispersed seeds appear to be more resilient to frag-mentation than species with e.g. small geographic ranges and gravity dispersed seeds. In addition, naturallyfragmented populations in the range margins may be more vulnerable than central populations as conditions forgene flow are generally impaired in peripheral areas. Traits important for adaptation (e.g. bud burst, bud set) arecontrolled by many genes, and as a corollary of fragmentation such genes are lost at a low rate. Large scalecommercial translocation of seeds and plants for forestry purposes applies mostly to conifers and dates backabout two centuries. Although many translocations have been successful in a forestry perspective, exposure tonew selective regimes has sometimes challenged the adaptive limits of populations and caused setbacks or evendiebacks of populations, as well as influencing neighbouring populations with maladapted genes (e.g. Scots pine,maritime pine, larch). Many tree species have substantial plasticity in fitness-related traits, which is vital forsurvival and viability following translocations. Selective logging has been practiced in Europe over the last twocenturies and implies removal of superior trees with respect to growth and quality. Such traits are partly undergenetic control. Consequent removal of superior trees may therefore have negative effects on the remaining genepool, but this effect will also be counteracted by extensive gene flow. Although humans have strongly affectedEuropean forest trees over the last millennia, we argue that they are still resilient from an evolutionary perspective.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Abstract
The effect of controlled nutrient feeding during the period of short day (SD) induction of flowering has been studied in three SD berry crops. An experimental system with standardized plant material grown with trickle fertigation in controlled environments was used. In strawberry, flowering was advanced and increased when an additional N pulse was given 1-2 weeks after commencement of a 4-week SD induction period, while the opposite resulted when the treatment was applied 2 weeks before start of SD. In blackcurrant, the highest flowering and yield were obtained when fertilization was applied shortly after the natural photoperiod had declined to the inductive length in September. While generous nutrient supply during spring and summer reduced berry soluble solids in blackcurrant, this was not observed with autumn fertilization. Autumn fertilization did not adversely affect plant winter survival or growth vigour in spring. Withdrawal of fertilization prior to, or at various stages during floral induction, did not significantly affect flowering and yield in raspberry, but marginally advanced flowering and fruit ripening.
Authors
Pauline Bristiel Lauren Gillespie Liv Østrem Jennifer Balachowski Cyrille Violle Florence VolaireAbstract
1. A core tenet of functional ecology is that the vast phenotypic diversity observed in the plant kingdom could be partly generated by a trade-off between the ability of plants to grow quickly and acquire resources in rich environments vs. the ability to conserve resources and avoid mortality under stress. However, experimental demonstrations remain scarce and potentially blurred by phylogenetic constraints in cross-species analyses. Here, we experimentally decoupled growth potential and stress survival by applying an off-season stress on contrasting populations of the perennial grass Dactylis glomerata exhibiting a range of seasonal dormancy.2. Seventeen populations of D. glomerata, originating from a latitudinal gradient from Norway to Morocco, were subjected to three types of dehydration stress: winter frost in Norway, and summer drought and early spring (off-season) drought stress in the south of France. Growth rate and two leaf traits (leaf width and leaf dry matter content) suspected to be involved in the adaptation to dehydration stress were monitored under optimal conditions. We quantified plant dehydration survival as the amount of plant recovery after a severe stress.3. Nordic populations were found to be winter-dormant. Winter- and summer-dor-mant populations better survived frost and summer drought, respectively. However, no trade-off between growth potential and dehydration survival was detected in non-dormant plants in early spring when dehydration occurred unsea-sonably for all populations. Furthermore, Mediterranean populations better survived an early spring drought.4. Our results highlight the importance of assessing plant growth potential as a re-sponse to seasonal environmental cues. They suggest that growth potential and stress survival trade off when plants exhibit seasonal dormancy but can be func-tionally independent at other seasons. Consequently, the growth–stress survival relationship could be better described as a dynamic linkage rather than a constant and general trade-off. Moreover, leaf trait values, such as thinner and more ligni-fied leaves reflecting drought adaptation, may have contributed to the improved drought-stress survival without resulting in a cost to growth. 5. Further exploration of the growth–stress survival relationship should permit deci-phering the suite of plant traits and trait covariations involved in plants’ responses to increasing stress.
Authors
Carrie Joy Andrew Einar Heegaard Klaus Høiland Beatrice Senn-Irlet Thomas W. Kuyper Irmgard Krisai-Greilhuber Paul M. Kirk Jacob Heilmann-Clausen Alan C. Gange Simon Egli Claus Bässler Ulf Büntgen Lynne Boddy Håvard KauserudAbstract
Here we assess the impact of geographically dependent (latitude, longitude, and altitude) changes in bioclimatic (temperature, precipitation, and primary productivity) variability on fungal fruiting phenology across Europe. Two main nutritional guilds of fungi, saprotrophic and ectomycorrhizal, were further separated into spring and autumn fruiters. We used a path analysis to investigate how biogeographic patterns in fungal fruiting phenology coincided with seasonal changes in climate and primary production. Across central to northern Europe, mean fruiting varied by approximately 25 d, primarily with latitude. Altitude affected fruiting by up to 30 d, with spring delays and autumnal accelerations. Fruiting was as much explained by the effects of bioclimatic variability as by their large‐scale spatial patterns. Temperature drove fruiting of autumnal ectomycorrhizal and saprotrophic groups as well as spring saprotrophic groups, while primary production and precipitation were major drivers for spring‐fruiting ectomycorrhizal fungi. Species‐specific phenology predictors were not stable, instead deviating from the overall mean. There is significant likelihood that further climatic change, especially in temperature, will impact fungal phenology patterns at large spatial scales. The ecological implications are diverse, potentially affecting food webs (asynchrony), nutrient cycling and the timing of nutrient availability in ecosystems.