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.
2017
Abstract
Creeping perennial weeds are of major concern in organically grown cereals. In the present study, the effects of different timing of mouldboard ploughing with or without a preceding stubble cultivation period, on weeds and spring cereals were studied. The experiments were conducted at two sites in Norway during a two and three-year period, respectively, with the treatments repeated on the same plots. The soil cultivation treatments were a stubble disc-harrowing cultivation period followed by mouldboard ploughing and only mouldboard ploughing. The timing of the treatments were autumn or spring. The density and biomass of the aboveground shoots of Cirsium arvense (L.) Scop., Elymus repens (L.) Gould, Sonchus arvensis L. and Stachys palustris L. as well as the total aboveground biomass of the spring cereal crop (oats) were assessed. The control efficiency of C. arvense and S. arvensis was closely related to timing of the cultivation treatments. Cultivation in spring decreased the population of C. arvense and S. arvensis compared to autumn cultivation. For E. repens, timing of the treatments had no significant effect: the important factor was whether stubble cultivation was carried out (best control) or not. The overall best strategy for controlling the present perennial weed population was stubble cultivation followed by ploughing in spring. However, the associated relative late sowing of the spring cereal crop and lowered crop biomass, were important drawbacks.
Abstract
No abstract has been registered
Authors
Nina Trandem Upendra Raj Bhattarai Isabelle Bueno Silva Karin Westrum Geir Kjølberg Knudsen Ingeborg KlingenAbstract
No abstract has been registered
Authors
Michelle T. Fountain Catherine Baroffio Anna-Karin Borg-Karlson Phil Brain Jerry V. Cross Dudley I. Farman David R. Hall Baiba Ralle Paolo Rendina Pauline Richoz Lene Sigsgaard Sverre Storberget Nina Trandem Atle WibeAbstract
Strawberry blossom weevil (SBW), Anthonomus rubi Herbst (Coleoptera: Curculionidae) and European tarnished plant bug (ETB), Lygus rugulipennis Poppius (Hetereoptera: Miridae), cause significant damage to strawberry and raspberry crops. Using the SBW aggregation pheromone and ETB sex pheromone we optimized and tested a single trap for both species. A series of field experiments in crops and seminatural habitats in five European countries tested capture of the target pests and the ability to avoid captures of beneficial arthropods. A Unitrap containing a trapping agent of water and detergent and with a cross vane was more efficient at capturing both species compared to traps which incorporated glue as a trapping agent. Adding a green cross vane deterred attraction of non-pest species such as bees, but did not compromise catches of the target pests. The trap caught higher numbers of ETB and SBW if deployed at ground level and although a cross vane was not important for catches of ETB it was needed for significant captures of SBW. The potential for mass trapping SBWand ETB simultaneously in soft fruit crops is discussed including potential improvements to make this more effective and economic to deploy.
Authors
Nina Trandem Arne Stensvand Joséphine Rehnfeldt Karin Westrum Dan H. Christensen Aksel Døving Jan Karstein HenriksenAbstract
No abstract has been registered
Authors
Umberto Salvagnin Mickael Malnoy Gunda Thöming Marco Tasin Silvia Carlin Stefan Martens Urska Vrhovsek Sergio Angeli Gianfranco AnforaAbstract
Herbivorous insects use olfactory cues to locate their host plant within a complex olfactory landscape. One such example is the European grapevine moth Lobesia botrana, a key pest of the grape in the Palearctic region, which recently expanded both its geographical and host plant range. Previous studies have showed that a synthetic blend of the three terpenoids, (E)-β-caryophyllene, (E)-β-farnesene and (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), was as attractive for the moth as the complete grape odour profile in laboratory conditions. The same studies also showed that the specific ratio of these compounds in the grape bouquet was crucial because a percentage variation in any of the three volatiles resulted in almost complete inhibition of the blend's attractiveness. Here, we report on the creation of stable grapevine transgenic lines, with modified (E)-β-caryophyllene and (E)-β-farnesene emission and thus with an altered ratio compared to the original plants. When headspace collections from these plants were tested in wind tunnel behavioural assays, they were less attractive than control extracts. This result was confirmed by testing synthetic blends imitating the ratio found on natural and transformed plants, as well as by testing the plants themselves. With this evidence, we suggest that a strategy based on volatile ratio modification may also interfere with the host-finding behaviour of L. botrana in the field, creating avenues for new pest control methods.
Authors
Umberto Salvagnin M. Malnoy Gunda Thöming M. Tasin S. Carlin S. Martens U. Vrhovsek S. Angeli G. AnforaAbstract
In nature plant terpenoids play multiple ecological roles. Many phytophagous insects use them as kairomones to locate their host plants. This is also the case for Lobesia botrana, which is the main pest of European vineyards. It was found that a specific blend of the terpenoids (E)-β-caryophyllene, (E)-β-farnesene and the homoterpene (E)-4,8-dimethyl-1,3,7-nonatriene emitted by grapevine was attractive to L. botrana females, and the attractiveness was shown to be dependent on the kairomone ratio. In this work, we generated stable grapevine transgenic lines with altered (E)-β-caryophyllene and (E)-β-farnesene emission compared to natural plants. Thus, we modified the ratio between these two kairomones in vivo, and tested how it affected L. botrana behaviour.
Abstract
No abstract has been registered
Abstract
We present a revised checklist of harvestmen (Opiliones) covering all the Nordic countries, including Iceland and the Faroe Islands. Altogether 31 species from 18 genera and four families are currently known, of which 23 are from Norway, 21 from Sweden, 17 from Finland, 25 from Denmark, five from the Faroe Islands and four from Iceland. Five species are documented for the first time in Norway: Lacinius dentiger (C. L. Koch, 1847), Lacinius horridus (Panzer, 1794), Opilio saxatilis C. L. Koch, 1839, Leiobunum blackwalli Meade, 1861 and Leiobunum limbatum L. Koch, 1861.
Abstract
A new subspecies of the European cerambycid Saperda populnea (Linnaeus, 1758) is described: Saperda populnea lapponica ssp. n. based on specimens from Scandinavia. The male genitalia characters were examined and found to provide support for this separation, as well as differences in morphology, geographical distribution and bionomy. The preferred host tree for the nominate subspecies S. populnea populnea is Populus tremula L., whereas S. populnea lapponica ssp. n. is considered to be monophagous on Salix lapponum L. DNA sequence data of mitochondrial cytochrome oxidase subunit I (COI) was generated from Scandinavian specimens of S. populnea populnea and specimens representing S. populnea lapponica ssp. n. The two subspecies were not reciprocally monophyletic and genetic distances in COI were small. All synonyms of S. populnea populnea have been considered, and species similar to S. populnea populnea have been examined, and not found to be related to S. populnea lapponica ssp. n. A male lectotype has been designated for each of the two following synonyms: Cerambyx decempunctatus De Geer, 1775, and Saperda salicis Zetterstedt, 1818. The synonymised species from Asia, S. balsamifera (Motshulsky, 1860), is elevated to subspecies: S. populnea balsamifera stat. n. We end with a discussion on the definition of subspecies under the unified species concept.