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.
2020
Authors
Juan Hu Yuanyuan Yao Yalin Yang Chenchen Gao Fengli Zhang Rui Xia Chao Ran Zhen Zhang Jihong Liu Clarke Zhigang ZhouAbstract
Probiotics confer a health benefit on the host and could be used as a good alternative to antibiotics. Probiotics are strain‐specific when exerting their function, so it is necessary to identify them to strain level. In recent years, intra‐species molecular typing and identification methods have developed rapidly, which commonly are used for typing the main pathogenic bacteria and rare for studies on probiotic typing, whilst it is imperative. This article describes molecular typing methods including AFLP, RAPD, PFGE, ribotyping, MLST, rep‐PCR and whole‐genome sequencing to identity some aquatic probiotics approved by the Ministry of Agriculture of China, which are Bifidobacterium, Enterococcus, Lactobacillus, Pediococcus, Aspergillus, Bacillus, Rhodopseudomonas palustris and Streptococcus thermophilus. In addition, the principles, applications, advantages and disadvantages of these typing methods are also discussed.
Abstract
Afforestation of marginal cultivated land is an internationally approved climate mitigation strategy, however, with uncertain implications for soil organic carbon (SOC) storage. We examined the effect of forest planting by measuring SOC at two adjacent sites: one with a Norway spruce forest planted in 1968 and one actively grazed pasture. Both sites had similar land-use history before forest planting, and they were as similar as possible in all other edaphic factors. There were no significant differences in SOC stocks down to 30 cm mineral soil, 7.15 and 8.51 kg C m−2 in the forest plantation and pasture respectively. Only a minimal build-up of an O horizon, less than 2 cm, was observed in the plantation. The SOC stocks of the plantation and pasture were not significantly different from that of a nearby old forest, 7.17 kg C m−2. When comparing these three land-uses we found that there were significant differences in the upper 10 cm of the soil with regard to other soil properties. Nitrogen (N) stock and pH were significantly lower in the old forest compared to the plantation, which again was significantly lower than that of the pasture. The opposite was the case for the C/N ratio. We conclude that there were no significant differences in SOC stocks in the upper 30 cm 50 years after afforestation with Norway spruce, but that there is still a legacy from the former cultivation that may influence both productivity and organic matter dynamics.
Authors
Svenja B. KroegerAbstract
No abstract has been registered
Authors
Arne BardalenAbstract
No abstract has been registered
Authors
Jukka Salonen Lars Olav Brandsæter Bärbel Gerowitt Jesper Rasmussen M-H. Robin Kirsten Tørresen Muriel Valantin-MorisonAbstract
No abstract has been registered
Authors
Tuuli Haikonen Jorunn Børve Timo Kaukoranta Pernilla Gabrielsson Michael Perander Päivi ParikkaAbstract
No abstract has been registered
Authors
Tuuli Haikonen Jorunn Børve Timo Kaukoranta Pernilla Gabrielsson Michael Perander Päivi ParikkaAbstract
No abstract has been registered
Authors
Hanno Sandvik Olga Hilmo Snorre Henriksen Reidar Elven Per Arvid Åsen Hanne Hegre Oddvar Pedersen Per Anker Pedersen Heidi Solstad Vigdis Vandvik Kristine Bakke Westergaard Frode Ødegaard Sandra Charlotte Helene Åström Hallvard Elven Anders Endrestøl Øivind Gammelmo Bjørn Arild Hatteland Halvor Solheim Björn Nordén Leif Sundheim Venche Talgø Tone Falkenhaug Bjørn Gulliksen Anders Jelmert Eivind Oug Jan Henry Sundet Elisabet Forsgren Anders Gravbrøt Finstad Trygve H. Hesthagen Kjell Harald Nedreaas Rupert Wienerroither Vivian Husa Stein Fredriksen Kjersti Sjøtun Henning Steen Haakon Hansen Inger Sofie Hamnes Egil Karlsbakk Christer Magnusson Bjørnar Ytrehus Hans Christian Pedersen Jon Swenson Per Ole Syvertsen Bård Gunnar Stokke Jan Ove Gjershaug Dag Dolmen Gaute Kjærstad Stein Ivar Johnsen Thomas Correll Jensen Kristian Hassel Lisbeth GederaasAbstract
1. Due to globalisation, trade and transport, the spread of alien species is increasing dramatically. Some alien species become ecologically harmful by threatening native biota. This can lead to irreversible changes in local biodiversity and ecosystem functioning, and, ultimately, to biotic homogenisation. 2. We risk-assessed all alien plants, animals, fungi and algae, within certain delimitations, that are known to reproduce in Norway. Mainland Norway and the Arctic archipelago of Svalbard plus Jan Mayen were treated as separate assessment areas. Assessments followed the Generic Ecological Impact Assessment of Alien Species (GEIAA) protocol, which uses a fully quantitative set of criteria. 3. A total of 1519 species were risk-assessed, of which 1183 were species reproducing in mainland Norway. Among these, 9% were assessed to have a severe impact, 7% high impact, 7% potentially high impact, and 49% low impact, whereas 29% had no known impact. In Svalbard, 16 alien species were reproducing, one of which with a severe impact. 4. The impact assessments also covered 319 so-called door-knockers, i.e. species that are likely to establish in Norway within 50 years, and 12 regionally alien species. Of the door-knockers, 8% and 10% were assessed to have a severe and high impact, respectively. 5. The impact category of most species was driven by negative interactions with native species, transformation of threatened ecosystems, or genetic contamination. The proportion of alien species with high or severe impact varied significantly across the different pathways of introduction, taxonomic groups, time of introduction, and the environments colonised, but not across continents of origin. 6. Given the large number of alien species reproducing in Norway and the preponderance of species with low impact, it is neither realistic nor necessary to eradicate all of them. Our results can guide management authorities in two ways. First, the use of quantitative assessment criteria facilitates the prioritisation of management resources across species. Second, the background information collected for each species, such as introduction pathways, area of occupancy and ecosystems affected, helps designing appropriate management measures.
Authors
Haftamu Gebretsadik Gebrehiwot Jens Bernt Aune Ole Martin Eklo Torfinn Torp Lars Olav BrandsæterAbstract
Allelopathic potential of 10 teff varieties was assessed in laboratory experimentation (conducted in NIBIO, Norway), and determined with an agar-based bioassay using ryegrass and radish as model weeds. Field experiments were conducted in Tigray, Ethiopia during 2015 and 2016 to identify the most important agronomic traits of teff contributing to its weed competitive ability. A split plot design with three blocks was used considering hand weeding as the main plot and varieties as the subplot. Randomized complete block design (RCBD) with four blocks was used in the laboratory experiment. The highest potential allelopathic activity (PAA) and specific potential allelopathic activity (SPAA) were recorded from a local landrace with an average PAA value of 11.77% and SPAA value of 1.21%/mg respectively, when ryegrass was used as the model weed. ‘Boset’ had the highest average PAA value of 16.25% and an SPAA value of 1.53%/mg, when using radish as the model weed. The lowest PAA and SPAA values were recorded from ‘DZ-Cr-3870 when using ryegrass and radish as model weeds. Days to emergence, height, tiller no./plant, biomass yield, and PAA of the crop significantly contributed to the variance of the weed biomass, cover, and density. Hence, they were the most important agronomic traits enhancing the competitive ability of teff.
Authors
Victor Rueda-Ayala Luis Ramos-Guerrero Paul Vargas-Jentzsch Betty Hernández Mats Höglind Ingrid Toscano Dayana Borja Lorena Goetschel Dionisio AndújarAbstract
In this study, aqueous extracts of Calliandra haematocephala Hassk. leaves and inforescences were tested on seeds of quinoa (Chenopodium album L.) and rice (Oryza sativa L.), and on some of the most noxious-associated weeds, Chenopodium album L. and Holcus lanatus L. in quinoa, and Echinochloa crus-galli (L.) P. Beauv., Echinochloa colona L., Eclipta prostrata L. and Rottboellia cochinchinensis (Lou.) W.D. Clayton in rice. The objectives were to identify extract concentrations at which 50 and 90% of germination (GR[50,90] ) and radicle elongation (RR[50,90] ) were inhibited, to fractionate inforescence extracts for facilitating identifying the chemical group causing allelopathic efects, and to evaluate the fraction showing the stronger weed suppression efects and the least crop damage. Increasing extract concentration rates (0, 6.25, 12.5, 25, 50 and 100% crude extract) were applied to seeds of target crops and weeds. Flower extracts at rates < 0.30 produced GR[50] and RR[50] on H. lanatus, and GR[90] and RR[90] in C. album, while quinoa seeds were not afected. Rice and its target weeds were minimally afected by fower extracts, whereas radicle elongation of all species was signifcantly reduced. A concentration rate > 0.52 caused the RR[50] on rice and all its target weeds. Fractions were quantitatively and qualitatively analysed to detect phytochemical groups, using specifc chemical reagents and thin-layer chromatography (TLC). The fraction F3 from aqueous fower extract showed a high content of favonoids, assumed as the potential allelochemical substance. Total favonoid content in F3 was quantifed as 2.7 mg of quercetin per g F3, i.e., 12.8 mg of quercetin per g of inforescence material. Additionally, feld equivalent extract rates obtained from the harvested fresh inforescence biomass could be determined. These rates ranged between 90 and 143 mL l −1 of F3 aqueous fraction, while for ethanol F3 were 131 mL l −1. Our results are encouraging for fnding sustainable and ecologically friendly alternatives for weed management in crops of high nutritional value, contributing also to counteract the growing problem of herbicide resistance.