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
Abstract
Due to an EU directive making integrated pest management (IPM) mandatory, European farmers are expected to reduce their use of chemical pesticides, which may potentially increase production costs and risk of harvest loss. Less pesticide use is appreciated by many consumers and may generate a higher willingness to pay (WTP). However, IPM is a wide concept and it is difficult for consumers to distinguish between products with high and low risk of pesticide residues. As a result, consumers might use other characteristics, such as country of origin, for the identification of safer products. In this study, we investigate if a higher WTP for Norwegian strawberries is associated with a belief that they contain less pesticide residues than imported berries. We use regression analysis to estimate to what extent the difference in WTP for Norwegian and imported strawberries is correlated with various perceptions about strawberries. The analyses reveal that the stronger the belief that Norwegian strawberries have less pesticide risk than imported ones, the higher the WTP for Norwegian strawberries. This means that if consumers believe domestic farmers use little pesticides, domestic products might be able to sell at considerably higher prices than imports. Hence, it may be economically beneficial for farmers to keep pesticide use at a minimum. Furthermore, we find that consumers have a higher WTP for strawberries produced with less use of pesticides, although not pesticide-free, indicating that IPM is appreciated.
Abstract
No abstract has been registered
Authors
Paal Krokene Bjørn Arild Hatteland Christer Magnusson Daniel Flø Iben Margrete Thomsen Johan A. Stenberg May Bente Brurberg Per Hans Micael Wendell Mogens Nicolaisen Simeon Rossmann Venche Talgø Beatrix Alsanius Sandra A.I. Wright Trond RafossAbstract
No abstract has been registered
Abstract
Simple Summary The bird cherry-oat aphid and the fungal plant pathogen causing stagonospora nodorum blotch (SNB) are common pests of wheat. Plants are under constant attack by multiple pests and diseases but there are limited studies on the interaction between several pests on wheat. We therefore conducted controlled greenhouse and laboratory experiments to determine how these pests affected each other on a wheat plant. We found that aphid feeding predisposed wheat to fungal disease, but that aphids preferred and reproduced better on leaves that had not been infected by the fungal pathogen. These results are important to understand the interactions between multiple pests on wheat and how to develop new control strategies in future integrated pest management (IPM). Abstract Wheat plants are under constant attack by multiple pests and diseases. Until now, there are no studies on the interaction between the aphid Rhopalosiphum padi and the plant pathogenic fungus Parastagonospora nodorum causal agent of septoria nodorum blotch (SNB) on wheat. Controlled experiments were conducted to determine: (i) The preference and reproduction of aphids on P. nodorum inoculated and non-inoculated wheat plants and (ii) the effect of prior aphid infestation of wheat plants on SNB development. The preference and reproduction of aphids was determined by releasing female aphids on P. nodorum inoculated (SNB+) and non-inoculated (SNB−) wheat leaves. The effect of prior aphid infestation of wheat plants on SNB development was determined by inoculating P. nodorum on aphid-infested (Aphid+) and aphid free (Aphid−) wheat plants. Higher numbers of aphids moved to and settled on the healthy (SNB−) leaves than inoculated (SNB+) leaves, and reproduction was significantly higher on SNB− leaves than on SNB+ leaves. Aphid infestation of wheat plants predisposed the plants to P. nodorum infection and colonization. These results are important to understand the interactions between multiple pests in wheat and hence how to develop new strategies in future integrated pest management (IPM).
2020
Abstract
The predatory mite Amblyseius andersoni (Acari: Phytoseiidae) is wanted as a new biocontrol product in Norwegian horticulture. The species was never found by Torgeir Edland, who surveyed the Norwegian fauna of phytoseiids for more than 20 years. Since A. andersoni has been found on blackberry in both Sweden and Denmark, we did a specific search for it in wild blackberry (Rubus tomentosus, sensu lato) in 2016. Almost 1500 potential phytoseiids were found on about 550 blackberry leaves collected near Sandefjord, Grimstad, Fredrikstad, and Ås. More than a third of these were examined at the Laboratory of Acarology (University of São Paulo, Brazil). Amblyseius andersoni was not found, but at least 10 other species of Phytoseiidae, all previously reported from Norway, were present. Thus, our survey supports earlier ones, indicating that A. andersoni is not naturally occurring in Norway. We conclude with some suggestions for an extended search.
Authors
Raimondas Mozūraitis David Hall Nina Trandem Baiba Ralle Kalle Tunström Lene Sigsgaard Catherine Baroffio Michelle Fountain Jerry Cross Atle Wibe Anna-Karin Borg-KarlsonAbstract
The strawberry blossom weevil (SBW), Anthonomus rubi, is a major pest in strawberry fields throughout Europe. Traps baited with aggregation pheromone are used for pest monitoring. However, a more effective lure is needed. For a number of pests, it has been shown that the attractiveness of a pheromone can be enhanced by host plant volatiles. The goal of this study was to explore floral volatile blends of different strawberry species (Fragaria x ananassa and Fragaria vesca) to identify compounds that might be used to improve the attractiveness of existing lures for SBW. Floral emissions of F. x a. varieties Sonata, Beltran, Korona, and of F. vesca, were collected by both solid-phase microextraction (SPME) and dynamic headspace sampling on Tenax. Analysis by gas chromatography/mass spectrometry showed the floral volatiles of F. x ananassa. and F. vesca were dominated by aromatic compounds and terpenoids, with 4-methoxybenzaldehyde (p-anisaldehyde) and α-muurolene the major compounds produced by the two species, respectively. Multi-dimensional scaling analyses separated the blends of the two species and explained differences between F. vesca genotypes and, to some degree, variation between F. x ananassa varieties In two-choice behavioral tests, SBW preferred odors of flowering strawberry plants to those of non-flowering plants, but weevils did not discriminate between odors from F. x ananassa and F. vesca flowering plants. Adding blends of six synthetic flower volatiles to non-flowering plants of both species increased the preference of SBW for these over the plants alone. When added individually to non-flowering plants, none of the components increased the preference of SBW, indicating a synergistic effect. However, SBW responded to 1,4-dimethoxybenzene, a major component of volatiles from F. viridis, previously found to synergize the attractiveness of the SBW aggregation pheromone in field studies.
Abstract
No abstract has been registered
Abstract
The invasive slug Arion vulgaris (Gastropoda: Arionidae) is an agricultural pest and serious nuisance in gardens of Central and Northern Europe. To investigate if the success of A.vulgaris in Norway can be attributed to a release from parasites, we compared the prevalence and parasite load of nematodes and trematodes in A. vulgaris to that of three native gastropod species, A. circumscriptus, A. fasciatus and Arianta arbustorum, in SE Norway. We found A. vulgaris to have the highest prevalence of both parasite groups (49% nematodes, 76% trematodes), which does not support the parasite release hypothesis, but rather points to A. vulgaris as a potentially important intermediate host of these parasites. For trematodes the number of individuals (parasite load) did not differ among host species; for nematodes it was higher in A. vulgaris than A. fasciatus. To further compare the parasite susceptibility of the surveyed gastropods, we exposed A. vulgaris, A. fasciatus, and A. arbustorum to a slug parasitic nematode, Phasmarhabditis hermaphrodita, in the laboratory. This nematode is commercially available and widely used to control A. vulgaris. The non-target species A. fasciatus was most affected, with 100% infection, 60% mortality and significant feeding inhibition. A. vulgaris was also 100% infected, but suffered only 20% mortality and little feeding inhibition. The load of P. hermaphrodita in infected specimens was not significantly different for the two Arion species (median: 22.5 and 45, respectively). Only 35% of A. arbustorum snails were infected, none died, and parasite load was very low (median: 2). However, they showed a near complete feeding inhibition at highest nematode dose, and avoided nematode-infested soil. Our results indicate that A. vulgaris may be less susceptible to P. hermaphrodita than the native A. fasciatus, and that non-target effects of applying this nematode in fields and gardens should be further investigated.
Authors
Rosemary Collier Dominique Mazzi Annette Folkedal Schjøll Quentin Schorpp Gunda Thöming Tor J. Johansen Richard Meadow Nicolai Vitt Meyling Anne-Marie Cortesero Ute Vogler Michael T. Gaffney Martin HommesAbstract
Several important vegetable crops grown outdoors in temperate climates in Europe can be damaged by the root-feeding larvae of Diptera (Delia radicum, Delia floralis, Chamaepsila rosae, Delia platura, Delia florilega, Delia antiqua). Knowledge of pest insect phenology is a key component of any Integrated Pest Management (IPM) strategy, and this review considers the methods used to monitor and forecast the occurrence of root-feeding flies as a basis for decision-making by growers and the ways that such information can be applied. It has highlighted some current management approaches where such information is very useful for decision support, for example, the management of C. rosae with insecticidal sprays and the management of all of these pests using crop covers. There are other approaches, particularly those that need to be applied at sowing or transplanting, where knowledge of pest phenology and abundance is less necessary. Going forward, it is likely that the number of insecticidal control options available to European vegetable growers will diminish and they will need to move from a strategy which often involves using a single ‘silver bullet’ to a combination of approaches/tools with partial effects (applied within an IPM framework). For the less-effective, combined methods, accurate information about pest phenology and abundance and reliable decision support are likely to be extremely important.
Authors
Jukka Salonen Lars Olav Brandsæter Bärbel Gerowitt Jesper Rasmussen M-H. Robin Kirsten Tørresen Muriel Valantin-MorisonAbstract
No abstract has been registered