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.
2016
Forfattere
Katja Karppinen Emese Derzso Laura Jaakola Anja HohtolaSammendrag
Hypericum perforatum L. is an important medicinal plant for the treatment of depression. The plant contains bioactive hypericins that accumulate in dark glands present especially in reproductive parts of the plant. In this study, pathogenesis-related class 10 (PR-10) family genes were identified in H. perforatum, including three previously unidentified members with sequence homology to hyp-1, a phenolic coupling protein that has earlier been suggested to participate in biosynthesis and binding/transportation of hypericin. The PR-10 genes showed constitutive but variable expression patterns in different H. perforatum tissues. They were all expressed at relatively high levels in leaves, variably in roots and low levels in stem and reproductive parts of the plant with no specific association with dark glands. The gene expression was up-regulated in leaves after salicylic acid, abscisic acid and wounding treatments but with variable levels. To study exact location of the gene expression, in situ hybridization of hyp-1 transcripts was performed and the accumulation of the Hyp-1 protein was examined in various tissues. The presence of Hyp-1 protein in H. perforatum tissues mostly paralleled with the mRNA levels. In situ RNA hybridization localized the hyp-1 transcripts predominantly in vascular tissues in root and stem, while in leaf the mRNA levels were high also in mesophyll cells in addition to vasculature. Our results indicate that the studied PR-10 genes are likely to contribute to the defense responses in H. perforatum. Furthermore, despite the location of the hyp-1 transcripts in vasculature, no support for the transportation of the Hyp-1 protein to dark glands was found in the current study. The present results together with earlier data question the role of the hyp-1 as a key gene responsible for the hypericin biosynthesis in dark glands of H. perforatum.
Forfattere
Yordanys R. González Orelvis Portal Erik Lysøe Annarella Chea Luis Rojas Nicolai Meyling Ingeborg KlingenSammendrag
The aim of this study was to evaluate the effect of conventional versus organic common bean (Phaseolus vulgaris) production on natural occurrence of Beauveria spp. as entophytes in bean plant tissue, from soil and as infections in stink bugs (Hemiptera: Pentatomidae), an important pest of bean in Cuba. Twenty-four organic and conventionally managed bean fields were sampled from September 2014 to April 2015 and Beauveria spp. were isolated and DNA extracted. PCR amplification of the intergenic Bloc region was performed for the identification of Beauveria species. Eighty-seven isolates were obtained from the soil samples by using the Galleria mellonella baiting technique. Further, 45 isolates were obtained from endophytic tissues of bean plant parts and 18 isolates were acquired from stink bugs. Only Beauveria bassiana was identified by DNA sequencing in this material. B. bassiana was more prevalent in soil, plant and stink bugs sampled from organic fields (41% soil, 22% plant, 9% bugs) compared to conventional fields (17% soil, 8% plant, 2% bugs). All plant parts were colonized by B. bassiana, but a significantly higher occurrence of this fungus was found in roots (9%) compared to stems (6%), leaves (4%) and pods (2%) in organic fields. In conventional fields there was a significantly higher occurrence of B. bassiana acquired from root (4%) and stem (3%) compared to leaves (1%) and pods (1%). Mating type PCR assays revealed that each of the isolates carried single mating types, with frequencies of 146/150 (MAT1) and 4/150 (MAT2), indicating limited potential for recombination. Our findings show that B. bassiana occur naturally as endophytes in bean fields in Cuba and contribute to a better ecological understanding of B. bassiana in agriculture.
Forfattere
Aruppillai Suthaparan Knut Asbjørn Solhaug Nils Bjugstad Hans Ragnar Gislerød David M. Gadoury Arne StensvandSammendrag
Disease-suppressive effects of nighttime applications of ultraviolet-B (UV-B) were investigated at two irradiance levels (1.6 or 0.8 W/m2) in strawberry and rosemary plants inoculated with Podosphaera aphanis or Golovinomyces biocellatus, respectively. Plants were exposed to each irradiance level every third night for either 9 or 18 min, every night for either 3 or 6 min, or three times every night for either 1 or 2 min. Thus, over time, all plants received the same cumulative dose of UV-B, and severity of powdery mildew was reduced by 90 to 99% compared with untreated controls in both crops. Use of polished aluminum lamp reflectors and UV-B reflective surfaces on greenhouse benches significantly increased treatment efficacy. An automated apparatus consisting of an adjustable boom with directed airflow was used to move UV-B lamps over greenhouse benches at 25 or 50 cm/min. Directed airflow moved leaves on the subtending plants to better expose upper and lower surfaces to UV-B but directed airflow actually decreased the efficacy of UV-B treatments, possibly by dispersing conidia from lesions before they were exposed to a lethal dose of UV-B. Results indicate broad applicability of nighttime applications of UV-B to suppress powdery mildews, and that cumulative UV-B dose is an overriding factor determining efficacy. Finally, enhanced suppression on shaded or obscured tissues is more likely to be affected by reflective bench surfaces than through attempts to physically manipulate the foliage.
Forfattere
Geethalakshmi V. Mehreteab Tesfai Lakshmanan A. Andrew Borrell Sekhar Udaya Nagothu M. S. Arasu Senthilraja K. Manikandan N. Sumathi S.Sammendrag
Det er ikke registrert sammendrag
Forfattere
Arne Melchior Ivar Alvik Tarjei Bekkedal Klaus Mittenzwei Ivar Pettersen Leo A. Grünfeld Marcus Gjems Theie Gabriel Felbermayr Frode Veggeland Hege MedinSammendrag
This study analyzes TTIP, its implications for Norway and Norway’s trade policy choices. TTIP will hardly be concluded under Obama's presidency, but the agreement could become a reality within a few years. TTIP aims at comprehensive cooperation in the regulatory area. In the short term there will be limited harmonization of standards but regulatory cooperation between different systems. In the long term, the goal is stronger cooperation in the regulatory area. TTIP will from what we know not lead to a lowering of European health regulations or a "race to the bottom". If TTIP is realized and Norway remains outside, the EEA Agreement will be little affected and the overall economic impact is moderate. If Norway joins TTIP, there will be a significant real income gain, with estimates ranging from 2236 to 6772 NOK per capita in the various scenarios. There is considerable variation across sectors. With Norway outside TTIP there will be a moderate negative impact for a majority of the sectors, especially some manufacturing sectors that face tougher competition in the EU and USA export markets. The oil industry will benefit from increased demand and higher prices. If Norway joins TTIP, a clear majority of industries will benefit; especially business services and a number of other service industries. The public sector gains from TTIP, mainly due to cheaper inputs. TTIP will contribute to the dismantling of import protection for Norwegian agriculture and without compensating measures, production and employment will be reduced. TTIP will still allow some import protection and this margin of maneuver, which depends on future negotiations, is important for the outcome. With a larger margin of manoeuvre and unchanged budgetarty support, most of Norway’s agriculture can be maintained. With less margin of manoeuvre, it will be more challenging. Norwegian accession to TTIP may occur in the form of a standard trade agreement in which Norway or EFTA are formally equal to the EU and the United States. Alternatively, Norway may participate in a European pillar as in today's "Open Skies" agreement on air traffic. If TTIP succeeds in establishing comprehensive regulatory cooperation, the latter solution is most likely. Such a solution implies that Norway will become more closely integrated with the European Union also in trade policy towards third countries. Norwegian entry into TTIP implies that we have to accept the established rules and negotiate bilaterally with the EU and the USA on market access. The negotiations with the USA will apply to all aspects of market access, while negotiations with the EU will apply only to areas in which the EEA agreement is not already deeper. The negotiations with the EU for TTIP entry will thus include, among other issues, tariffs for seafood and agriculture. As an alternative to membership in TTIP, Norway or EFTA may initiate a trade agreement with the USA. Such an agreement would likely be less extensive in the regulatory area. Such an agreement will also provide an economic gain for Norway, but less than accession to TTIP. For Norway as a whole, accession to TTIP creates a real income gain between 12.5 and 35 billion NOK according to various scenarios, while a free trade agreement with the United States results in a gain of about 7.4 billion NOK. TTIP also includes negotiations on so-called Investor-State Dispute Settlement (ISDS), whereby foreign-owned companies can sue a state if they are unfairly or inappropriately treated. Such rights also exist in national law but international tribunals have to some extent extended the interpretation of what is considered unfair. The European Union has proposed a solution in TTIP with a permanent court as well as rules that discipline the interpretation of the principles, and thus avoids that ISDS unduly interferes into the states’ "right to regulate". This and many other issues are analysed in this report and six background papers.
Forfattere
Mathias Neumann Adam Moreno Christopher Thurnher Volker Mues Sanna Härkönen Matteo Mura Olivier Bouriaud Mait Lang Giuseppe Cardellini Alain Thivolle-Cazat Karol Bronisz Jan Merganic Iciar Alberdi Rasmus Astrup Frits Mohren Maosheng Zhao Hubert HasenauerSammendrag
Net primary production (NPP) is an important ecological metric for studying forest ecosystems and their carbon sequestration, for assessing the potential supply of food or timber and quantifying the impacts of climate change on ecosystems. The global MODIS NPP dataset using the MOD17 algorithm provides valuable information for monitoring NPP at 1-km resolution. Since coarse-resolution global climate data are used, the global dataset may contain uncertainties for Europe. We used a 1-km daily gridded European climate data set with the MOD17 algorithm to create the regional NPP dataset MODIS EURO. For evaluation of this new dataset, we compare MODIS EURO with terrestrial driven NPP from analyzing and harmonizing forest inventory data (NFI) from 196,434 plots in 12 European countries as well as the global MODIS NPP dataset for the years 2000 to 2012. Comparing these three NPP datasets, we found that the global MODIS NPP dataset differs from NFI NPP by 26%, while MODIS EURO only differs by 7%. MODIS EURO also agrees with NFI NPP across scales (from continental, regional to country) and gradients (elevation, location, tree age, dominant species, etc.). The agreement is particularly good for elevation, dominant species or tree height. This suggests that using improved climate data allows the MOD17 algorithm to provide realistic NPP estimates for Europe. Local discrepancies between MODIS EURO and NFI NPP can be related to differences in stand density due to forest management and the national carbon estimation methods. With this study, we provide a consistent, temporally continuous and spatially explicit productivity dataset for the years 2000 to 2012 on a 1-km resolution, which can be used to assess climate change impacts on ecosystems or the potential biomass supply of the European forests for an increasing bio-based economy. MODIS EURO data are made freely available at ftp://palantir.boku.ac.at/Public/MODIS_EURO.
Forfattere
Roger RosethSammendrag
Utbyggingsprosjektet E18 Bommestad – Sky har deponert bunnrenskemasser (BRM) fra tunneldriving på massedeponiet ved Langemyr i henhold til definert prosedyre med prøvetaking og kontroll av innkjørte masser. Prosedyren omfattet uttak av blandprøver for analyse av alifatiske hydrokarboner for hver 100 m3 kjørt til deponiet. Normverdi for alifatiske hydrokarboner (>C12-C35) er 100 mg/kg i følge forurensningsforskriften. Akseptkriteriet er basert på statistisk grunnlag og er satt til aritmetisk middel lavere enn 100 mg/kg og 90-persentil mindre enn 2 ganger normverdi (200 mg/kg). Basert på disse kriteriene har det blitt gjort en løpende vurdering av resultatene for totalvolum BRM tilkjørt deponiet. Fortolkningen av regelverket gir rom for usikkerhet vedrørende hvilke masser som bør kjøres til annen deponering. For totalvolumet av BRM tilkjørt deponiet har undersøkelsene vist at kravet til innhold av alifatiske hydrokarboner er tilfredsstilt, både med hensyn til aritmetisk middel og innenfor 90-persentil. Innholdet av alifatiske hydrokarboner i massene varierer noe. Innholdet av alifatiske hydrokarboner kan være marginalt høyere en normverdi dersom man betrakter mindre volum/områder BRM. Enkelte mindre områder kan ha et høyere innhold av alifatiske hydrokarboner, samtidig som akseptkriteriene er tilfredsstilt. Antall målinger utført gir en god dokumentasjon av innholdet av alifatiske hydrokarboner i BRM. Gjennomført risikovurdering har vurdert deponering av BRM på Langemyr, med vekt på innhold av alifatiske hydrokarboner. Herunder risiko for miljø, liv/helse og infrastruktur/eiendom. Det er gjort tiltak som skal forebygge teoretisk risiko for utvasking av hydrokarboner fra BRM og for å minimere eksponering mot dyr og mennesker. Samlet sett gir gjennomført deponering av BRM lav risiko for miljø, liv/helse og infrastruktur/eiendom. For vannmiljø bygger vurderingen blant annet på at analyser har vist at hydrokarbonene består av tyngre forbindelser (C12-C35) som har lav mobilitet og gir liten fare for utlekking til vassdrag. Hydrokarbonene forventes å være sterkt bundet til finmasser i BRM. Over tid vil de brytes ned eller forbli bundet som inerte forbindelser. For økt sikkerhet med hensyn til utlekking gjennomføres det ett oppfølgingsprogram for analyse av alifatiske hydrokarboner i Hagabekken nedstrøms deponiet. Innledningsvis med månedlig prøvetaking. Etter et år evalueres det om videre oppfølging er nødvendig. De innledende analyseomgangene har ikke vist spor av olje i bekken. I henhold til YM-planen for E18 Bommestad – Sky ble det satt krav om at Hagabekken ikke skal tilføres anleggsvann med innhold av hydrokarboner over 10 mg THC/l. Til sammenligning er det lite sannsynlig at utlekking av oljeforbindelser fra Langemyr deponi vil gi opphav til sporbare konsentrasjoner av olje i Hagabekken. Risikoen for at alifatiske hydrokarboner i BRM vaskes ut og gir uheldige miljøeffekter på vannkvaliteten i Hagabekken/ Norbytjern vurderes som lav.
Sammendrag
Stem elongation and flower bud emergence in response to photoperiod (16 and 20 h) and temperature (10, 14 and 18 °C) were characterized in three Norwegian (Lea, Nordi, Reipo) and one Swiss (Fregata) red clover variety. The Norwegian varieties were slower in generative development than Fregata, and were, unlike Fregata, responsive to an increase in photoperiod from 16 to 20 h. Lea was later than Reipo, while Nordi was intermediate. Across all varieties, the earliness of stem elongation in response to temperature was saturated at 14 °C, whereas earliness of flower bud emergence also responded to an increase from 14 to 18 °C. Photoperiod and temperature had additive effects on timing of development prior to stem elongation and complementary effects on timing of development prior to flower bud emergence. Developmental rates calculated on a thermal time basis varied between temperature treatments.
Sammendrag
Biochar and its properties can be significantly altered according to how it is produced, and this has ramifications towards how biochar behaves once added to soil. We produced biochars from corncob and miscanthus straw via different methods (slow pyrolysis, hydrothermal and flash carbonization) and temperatures to assess how carbon cycling and soil microbial communities were affected. Mineralization of biochar, its parent feedstock, and native soil organic matter were monitored using 13C natural abundance during a 1-year lab incubation. Bacterial and fungal community compositions were studied using T-RFLP and ARISA, respectively. We found that persistent biochar-C with a half-life 60 times higher than the parent feedstock can be achieved at pyrolysis temperatures of as low as 370 °C, with no further gains to be made at higher temperatures. Biochar re-applied to soil previously incubated with our highest temperature biochar mineralized faster than when applied to unamended soil. Positive priming of native SOC was observed for all amendments but subsided by the end of the incubation. Fungal and bacterial community composition of the soil-biochar mixture changed increasingly with the application of biochars produced at higher temperatures as compared to unamended soil. Those changes were significantly (P < 0.005) related to biochar properties (mainly pH and O/C) and thus were correlated to pyrolysis temperature. In conclusion, our results suggest that biochar produced at temperatures as low as 370 °C can be utilized to sequester C in soil for more than 100 years while having less impact on soil microbial activities than high-temperature biochars.
Sammendrag
Black currant is a woody plant in which growth and development are intimately controlled by, and synchronised with seasonal changes in photoperiod and temperature. Concern over the potential impact of global warming on plant phenology and yield, led us to initiate relations. An experimental system with single-stemmed potted plants was developed which allowed a research program to address both qualitative and quantitative assessment of climatic responses. Growth cessation and flowering were both induced by short days, with critical photoperiods of approximately 17 and 16 h, respectively, for most cultivars. Both processes were advanced and promoted by increasing autumn temperature with an optimum in the 18-21°C region. An exception was cultivars of high-boreal origin, which had an early growth cessation at low temperature. Unexpectedly, however, not all plants flowered after exposure to 10 h photoperiod, and the number of flowers decreased as the photoperiod was reduced from the near-critical length of 15 h. This was due to premature dormancy induced by an abrupt change to photoperiods well below the critical level. Field experiments revealed that cultivars of varying geographic origin, exhibited a typical latitudinal cline in their photoperiodically controlled timing of growth and flowering responses. Breaking of bud dormancy and promotion of flower bud development required chilling at -5°C for 14 weeks or more for optimal responses. However, while chilling at -10°C for 8 weeks resulted in dormancy release, continued chilling to 16 weeks inhibited bud break completely. We therefore propose that excessive chilling induces secondary bud dormancy in black currant. The observed high chilling requirements of black currants concur with the reported vulnerability of this crop to declining winter chill in the wake of the ongoing global warming. Furthermore, such conditions also induce a particularly deep bud dormancy state that further increases the chilling need.