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.
2021
Authors
Ying Yen Ralf Rautenberger Martin Riis Weisbjerg Adriána Fečkaninová Margarita Novoa-GarridoAbstract
No abstract has been registered
Authors
Venche Talgø Martin Pettersson Magnhild Sekse Erdal May Bente Brurberg Sigrid Mogan Arne StensvandAbstract
No abstract has been registered
Authors
Sigridur DalmannsdottirAbstract
No abstract has been registered
Authors
Irina Orestovna Averkina Muhammad Harris Edward Ohene Asare Bérénice Hourdin Ivan Paponov Cathrine LilloAbstract
Background PROTEIN PHOSPHATASE 2A (PP2A) expression is crucial for the symbiotic association between plants and various microbes, and knowledge on these symbiotic processes is important for sustainable agriculture. Here we tested the hypothesis that PP2A regulatory subunits, especially B’φ and B’θ, are involved in signalling between plants and mycorrhizal fungi or plant-growth promoting bacteria. Results Treatment of tomato plants (Solanum lycopersicum) with the plant growth-promoting rhizobacteria (PGPR) Azospirillum brasilense and Pseudomonas simiae indicated a role for the PP2A B’θ subunit in responses to PGPR. Arbuscular mycorrhizal fungi influenced B’θ transcript levels in soil-grown plants with canonical arbuscular mycorrhizae. In plant roots, transcripts of B’φ were scarce under all conditions tested and at a lower level than all other PP2A subunit transcripts. In transformed tomato plants with 10-fold enhanced B’φ expression, mycorrhization frequency was decreased in vermiculite-grown plants. Furthermore, the high B’φ expression was related to abscisic acid and gibberellic acid responses known to be involved in plant growth and mycorrhization. B’φ overexpressor plants showed less vigorous growth, and although fruits were normal size, the number of seeds per fruit was reduced by 60% compared to the original cultivar. Conclusions Expression of the B’θ gene in tomato roots is strongly influenced by beneficial microbes. Analysis of B’φ overexpressor tomato plants and established tomato cultivars substantiated a function of B’φ in growth and development in addition to a role in mycorrhization. Keywords: Abscisic acid, Azospirillum brasilense, Funneliformis mosseae, Gibberellin, Mycorrhiza, PP2A, PGPR, Pseudomonas simiae, Rhizophagus irregularis, Tomato
Abstract
No abstract has been registered
Authors
Kemeng Xiao Karin Juul Hesselsøe Christer Magnusson Tatsiana Espevig Trond Olav Pettersen Trygve S. AamlidAbstract
In 2018–2019, establishment problems were encountered, after reseeding creeping bentgrass (Agrostis stolonifera) on a sand-based putting green after ice encasement at the NIBIO Turfgrass Research Center, Norway. Seeds germinated, but the seedlings attained a purple color and died in large patches. Replacement of the top 3 cm layer with new sand amended with Sphagnum peat or garden compost did not solve the problem. To explain this phenomenon, we (1) analyzed the original substrate for nematodes in patches with and without reestablishment failure; and (2) conducted a factorial pot trial with creeping bentgrass and Chewings fescue (Festuca rubra ssp. commutata) seeded on different substrates, some of them in layers, and with and without phosphorus (P) fertilization. The nematode counts showed six times more stubby-root nematodes and two times more spiral nematodes and needle nematodes in the patches with dead seedlings than in the patches with healthy seedings. In the pot trial, the fastest and slowest reestablishment was observed with new sand amended with garden compost and in the two treatments that included the original substrate, respectively. Replacement of the top 3 cm of the old substrate with new garden compost resulted in stagnation of bentgrass seedlings from four weeks after seeding, while fescue seedlings were unaffected. We conclude that the failure to reestablish creeping bentgrass was primarily due to nematodes, which are likely to be more critical for seedlings than for established turf. The green was later reestablished successfully with a 100 % red fescue seed blend.
Abstract
Aquaculture has undergone rapid development in the past decades. It provides a large part of high-quality protein food for humans, and thus, a sustainable aquaculture industry is of great importance for the worldwide food supply and economy. Along with the quick expansion of aquaculture, the high fish densities employed in fish farming increase the risks of outbreaks of a variety of aquatic diseases. Such diseases not only cause huge economic losses, but also lead to ecological hazards in terms of pathogen spread to marine ecosystems causing infection of wild fish and polluting the environment. Thus, fish health is essential for the aquaculture industry to be environmentally sustainable and a prerequisite for intensive aquaculture production globally. The wide use of antibiotics and drug residues has caused intensive pollution along with risks for food safety and increasing antimicrobial resistance. Vaccination is the most effective and environmentally friendly approach to battle infectious diseases in aquaculture with minimal ecological impact and is applicable to most species of farmed fish. However, there are only 34 fish vaccines commercially available globally to date, showing the urgent need for further development of fish vaccines to manage fish health and ensure food safety. Plant genetic engineering has been utilized to produce genetically modified crops with desirable characteristics and has also been used for vaccine production, with several advantages including cost-effectiveness, safety when compared with live virus vaccines, and plants being capable of carrying out posttranslational modifications that are similar to naturally occurring systems. So far, plant-derived vaccines, antibodies, and therapeutic proteins have been produced for human and animal health. However, the development of plant-made vaccines for animals, especially fish, is still lagging behind the development of human vaccines. The present review summarizes the development of fish vaccines currently utilized and the suitability of the plant-production platform for fish vaccine and then addresses considerations regarding fish vaccine production in plants. Developing fish vaccines by way of plant biotechnology are significant for the aquaculture industry, fish health management, food safety, and human health.
Authors
Selamawit Araya Kidane Solveig Haukeland Beira H. Meressa Anne Kathrine Hvoslef-Eide Danny L. CoyneAbstract
Enset (Ensete ventricosum), is a perennial herbaceous plant belonging to the family Musaceae, along with banana and plantain. Despite wild populations occurring in eastern, central and southern Africa, it is only in Ethiopia that the crop has been domesticated, where it is culturally and agriculturally symbolic as a food security crop. Although an under-researched orphan crop, enset serves as a staple food for about 20% of the Ethiopian population, comprising more than 20 million people, demonstrating its value in the country. Similar to banana and plantain, enset is heavily affected by plant-parasitic nematodes, with recent studies indicating record levels of infection by the root lesion nematode Pratylenchus goodeyi. Enset is propagated vegetatively using suckers that are purposely initiated from the mother corm. However, while banana and plantain suckers have proven to be a key source of nematode infection and spread, knowledge on the infection levels and role of enset suckers in nematode dissemination is lacking. Given the high levels of plant-parasitic nematodes reported in previous surveys, it is therefore speculated that planting material may act as a key source of nematode dissemination. To address this lack of information, we assessed enset planting material in four key enset growing zones in Ethiopia. A total of 340 enset sucker samples were collected from farmers and markets and analyzed for the presence of nematodes. Nematodes were extracted using a modified Baermann method over a period of 48 h. The root lesion nematode P. goodeyi was present in 100% of the samples, at various levels of infection. These conclusive results show that planting material is indeed a key source of nematode infection in enset, hence measures taken to ensure clean suckers for planting will certainly mitigate nematode infection and spread. The effect of nematode infection on yield and quality on enset remains to be investigated and would be a way forward to complement the nematode/disease studies conducted so far and add valuable knowledge to the current poorly known impact of pests and diseases.
Authors
Pia Heltoft Thomsen Gudni Thorvaldsson Anne Mette Dahl Jensen Tatsiana Espevig Karin Juul Hesselsøe Wendy Marie Waalen Torben Kastrup Petersen Trond Olav Pettersen Jan Tangsveen Per Sørensen Tania Gneist Bjarni Hannesson Kristine Sundsdal Trygve S. AamlidAbstract
Seed mixtures with a nurse grass that germinates quickly at low soil temperatures can be an option for faster establishment of Agrostis stolonifera (AS) putting greens after winter damage. From 2015 to 2018 Poa trivialis (PT) ‘Dark Horse’ and Lolium perenne (LP) ‘Chardin’ were evaluated as nurse grasses in comparison with pure AS ‘Independence’ at two experimental sites in each of the two major climatic zones of the Nordic countries. Poa annua (PA) ‘Two‐Putt’ was also included as a nurse grass in the northern zone. As an overall trend, establishment was faster with AS+LP than with AS+PT and AS+PA, which in turn had faster establishment than pure AS. In the northern zone, AS+PT produced better turf quality than pure AS in the seeding year and year after and tended to be superior even on average for the entire trial period (mean value 6.0 vs. 5.8 for pure AS, 5.3 for AS+LP, and 4.6 for AS+PA; scale 1–9 where 9 is the highest quality). In the same zone, AS+PT also suffered less overall winter damage than the other combinations and was less infected with microdochium patch than pure AS. In the southern zone, PT and especially LP were far more persistent than in the northern zone and compromised turfgrass quality compared with pure AS. In conclusion, we recommend PT as a nurse grass for faster establishment of AS putting in the northern zone, but not in the southern zone where AS should rather be seeded in a pure stand.
Abstract
The Norwegian newly bred pear cultivar, ‘Celina/QTee®’, which was launched in 2010, has been released from the Norwegian breeding program. It derived from the combination ‘Colourée de Juillet’ × ‘Williams’. In Norway the flowering is medium to late in May and it ripens in the beginning of September. It has large attractive fruits with red blush and good fruit quality, storability and shelf life. Significant areas of ‘Celina’ cultivars are planted in other countries, mainly Europe. Generally, unfavourable environmental conditions for pear pollination during the Nordic spring can have a very negative effect on the yields in Norwegian pear orchards. Therefore, it is of considerable importance to interplant multiple suitable pollinizer genotypes together with the main cultivar. In order to find the right pollinizers besides following biology of fertilization, pollinizing efficacy using microsatellites were studied at NIBIO Ullensvang, western Norway. In this study, during 2017, seeds from fruits of the pear cultivar ‘Celina’ were extracted. The fruits were randomly harvested from five different orchards located in Ullensvang including NIBIO. Alongside the seeds, leaves were taken from the mother cultivar (‘Celina’) and five pear pollinizer cultivars presented in the orchards (‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’). Using 11 microsatellite markers, a genetic characterization was conducted on both the seeds and the leaves. The obtained SSR profiles were used for gene assignment analyses. The results of the genetic analyses indicate a very heterogeneous situation regarding pollination. In conclusion, ‘Fritjof’, ‘Kristina’, ‘Clara Frijs’, ‘Herzogine Elsa’ and ‘Anna’ pears had different pollen contributions as pollinizers to ‘Celina’ depending on the investigated orchard. Only one cultivar (‘Herzogine Else’) could be singled out as a major pollen contributor in more than two orchards. Genetic analyses will be repeated in the same orchards, during an additional season, after which more conclusive results will be available.