1. |
- Abreha, Kibrom Berhe, et al.
(författare)
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Phosphite protects against potato and tomato late blight in tropical climates and has varying toxicity depending on the Phytophthora infestans isolate
- 2019
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 121, s. 139-146
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Tidskriftsartikel (refereegranskat)abstract
- Late blight caused by the oomycete Phytophthora infestans is one of the most severe diseases of potato (Solarium tuberosum L.) and tomato (Solarium lycopersicum L.). In this study, field trials were conducted in a cool tropical highland of Ethiopia for three consecutive years to investigate the efficacy of phosphite alone and in combination with conventional fungicide against late blight in two potato cultivars and one tomato cultivar. Phosphite alone and in combination with reduced dosages of the fungicide Ridomil (mancozeb 64% and metalaxyl-M 4% (w/w)) led to effective suppression of late blight in research plots and in farmers' fields under light-to-normal late blight pressure. However, phosphite was not as effective as the fungicide under high disease pressure. Notably, phosphite was more effective against tomato late blight than against potato late blight, and gave the same protection as the fungicide in tomato. In vitro assays showed small differences in sensitivity to phosphite among five European and two Ethiopian isolates of P. infestans in terms of radial growth, sporangium production and sporangium germination, which could affect the population structure. Since phosphite can be provided at a lower price than conventional fungicides, it can reduce expenses for Ethiopian farmers with preserved late blight control.
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2. |
- Baroffio, C. A., et al.
(författare)
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Combining plant volatiles and pheromones to catch two insect pests in the same trap : Examples from two berry crops
- 2018
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Ingår i: Crop Protection. - : ELSEVIER SCI LTD. - 0261-2194 .- 1873-6904. ; 109, s. 1-8
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Tidskriftsartikel (refereegranskat)abstract
- Most horticultural crops are attacked by more than one insect pest. As broad-spectrum chemical control options are becoming increasingly restricted, there is a need to develop novel control methods. Semiochemical attractants are available for three important horticultural pests, strawberry blossom weevil, Anthonomus rubi Herbst (Coleoptera: Curculionidae), European tarnished plant bug, Lygus rugulipennis Poppius (Hemiptera: Miridae) and raspberry beetle, Byturus tomentostts deGeer (Coleoptera: Byturidae). Traps targeting more than one pest species would be more practical and economical for both monitoring and mass trapping than traps for single-species. In this study we aimed to (1) improve the effectiveness of existing traps for insect pests in strawberry and raspberry crops by increasing catches of each species, and (2) test if attractants for two unrelated pest species could be combined to capture both in the same trap without decreasing the total catches. Field tests were carried out in four European countries and different combinations of semiochemicals were compared. A volatile from strawberry flowers, 1,4 dimethoxybenzene (DMB), increased the attractiveness of the aggregation pheromone to both sexes of A. rubi. The host-plant volatile, phenylacetaldehyde (PAA), increased the attraction of female L. rugulipennis to the sex pheromone, and, in strawberry, there was some evidence that adding DMB increased catches further. Traps baited with the aggregation pheromone of A. rubi, DMB, the sex pheromone of L rugulipennis and PAA attracted both target species to the same trap with no significant difference in catches compared to those single-species traps. In raspberry, catches in traps baited with a combination of A. rubi aggregation pheromone, DMB and the commercially available lure for B. tomentosus, based on raspberry flower volatiles, were similar to those in single-species traps. In both crops the efficiency of the traps still needs improvement, but the multi species traps are adequate for monitoring and should not lead to confusion for the user as the target species are easy to distinguish from each other.
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3. |
- Cotes Ramal, Belén, et al.
(författare)
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A first approach to pest management strategies using trap crops in organic carrot fields
- 2018
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 112, s. 141-148
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Tidskriftsartikel (refereegranskat)abstract
- Cultural control methods in integrated pest management (IPM) refer to practices that modify the agricultural environment in ways that favour crop protection to the detriment of pest performance. Trap cropping is one of these practices and involves luring insect pests away from the main crop to a more attractive host plant growing beside or around the crop. The trap crop can then be destroyed, and the pest killed. The carrot psyllid, Trioza apicalis Forster (Homoptera: Triozidae), is one of the most important carrot pests in Scandinavia, and cultural control of this pest could be achieved through the introduction of more attractive cultivars of carrots in the trap crop at different sowing times than used for the main crop. In a multichoice bioassay and a field experiment, T. apicalis females oviposited the highest numbers of eggs on the most developed carrot plants in the trap crop, while different carrot cultivars did not play any role in females' choice, In the field experiment, probability of damage was highly correlated with number of eggs counted on the plants, which was highest on the most developed plants. The cultivar Bolero was used as trap crop in subsequent trials in three commercial carrot fields in different regions of Sweden. The trap crop concentrated the egg laying to the field edges and it decreased with increasing distance within the main crop from the first row of carrots, while this pattern could not be observed in control plots. These first results are promising, but further trials to better quantify efficacy and to evaluate the spatial design of the trap crop in field, at different sites and population pressure, are needed before trap cropping can be a reliable strategy for carrot psyllid control.
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4. |
- Djurle, Annika
(författare)
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An outlook on wheat health in Europe from a network of field experiments
- 2021
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 139
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Tidskriftsartikel (refereegranskat)abstract
- Wheat disease management in Europe is mainly based on the use of fungicides and the cultivation of resistant cultivars. Improving disease management implies the formal comparison of disease management methods in terms of both crop health and yield levels (attainable yield, actual yield), thus enabling an assessment of yield losses and yield gains. Such an assessment is not available for wheat in Europe. The objective of the analysis reported here is to provide an overview of wheat health and yield performance in field experiments in Europe. Data from field experiments in six European countries (Belgium, France, Germany, Italy, Norway, and Sweden) conducted between 2013 and 2017 were analysed to that aim. Relationships between multiple disease levels, yield, level of cultivar resistance, level of fungicide protection, and weather patterns were assessed. The analyses included 73 field experiments, corresponding to a total of 447 [fungicide protection level x cultivar] combinations. Analyses across the six countries led to ranking the importance of foliar wheat diseases as follows, in decreasing order: leaf blotch (septoria tritici blotch, septoria nodorum blotch, and tan spot), leaf rust, yellow rust, and powdery mildew. Fusarium head blight was observed in France and Italy, and stem rust was sporadically observed in Italy. Disease patterns, crop inputs (fertiliser, fungicides), and yields widely varied within and across countries. Disease levels were affected by the level of fungicide use, by cultivar resistance, as well as by weather patterns. While this analysis enables a better documentation of the status of wheat health in Europe, it also highlights the critical need for policies in Europe enabling a more judicious use of pesticides. First, common standards for field experiments are needed (experimental designs and protocols; disease assessment procedures and scales; references, including reference-susceptible cultivars); second, assessments in farmers' fields - and not in research stations - are necessary; and third, there is a need to use available process-based crop models to estimate attainable yields, and so, yield losses.
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5. |
- Edin, Eva
(författare)
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Species specific primers for identification of Alternaria solani, in combination with analysis of the F129L substitution associates with loss of sensitivity toward strobilurins
- 2012
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 38, s. 72-73
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Tidskriftsartikel (refereegranskat)abstract
- A species specific forward primer was designed in order to identify the phytopathogenic fungus Alternaria solani, which causes early blight on potato. The reverse primer came from another survey of the American population of A. solani. The combination of these two primers can be used both as molecular identification of A. solani as well as sending the PCR product for sequencing in search for the F129L substitution associated with loss of sensitivity toward fungicides based on strobilurins. The diagnostic method has been successfully used when identifying the causal agent of lesions on potato leaflets during large field assays. (C) 2012 Elsevier Ltd. All rights reserved.
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6. |
- Ekbom, Barbara
(författare)
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Flea beetle (Phyllotreta undulata Kutschera) sensitivity to insecticides used in seed dressings and foliar sprays
- 2011
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 30, s. 1376-1379
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Tidskriftsartikel (refereegranskat)abstract
- Flea beetles of the genus Phyllotreta (Coleoptera: Chrysomelidae), which are severe pests in spring oilseed rape, have become increasingly difficult to control in some areas in Sweden. The current practice for plant protection is to use seed treatments followed by foliar applications of insecticide. Seed treatment with the single, currently registered neonicotinoid insecticide (active ingredient: imidacloprid) was compared to untreated controls and seed treatment with clothianidin using Phyllotreta undulata Kutschera beetles from 10 locations. Beetles from the overwintered generation and the new generation from the same 10 locations were used in bioassays to detect possible reduced sensitivity to the pyrethroid lambda-cyhalothrin. Seed treatment with clothianidin provided better protection for seedlings than imidacloprid. Highly variable results were obtained from the pyrethroid bioassays, but tests performed on beetles collected in August indicated that most sampled beetle populations are still susceptible to lambda-cyhalothrin. It is, however, important that the need for foliar applications is minimized to avoid insecticide resistance selection pressure. This requires seed treatments with adequate efficacy against flea beetles together with cultural control measures that can reduce flea beetle damage. (C) 2011 Elsevier Ltd. All rights reserved.
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7. |
- Fountain, M. T., et al.
(författare)
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Design and deployment of semiochemical traps for capturing Anthonomus rubi Herbst (Coleoptera : Curculionidae) and Lygus rugulipennis Poppius (Hetereoptera: Miridae) in soft fruit crops
- 2017
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Ingår i: Crop Protection. - : Elsevier. - 0261-2194 .- 1873-6904. ; 99, s. 1-9
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Tidskriftsartikel (refereegranskat)abstract
- 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 semi-natural 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 SBW and ETB simultaneously in soft fruit crops is discussed including potential improvements to make this more effective and economic to deploy.
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8. |
- Hagnell, J, et al.
(författare)
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How to trap a slug: Commercial versus homemade slug traps
- 2006
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Ingår i: Crop Protection. - : Elsevier BV. - 1873-6904 .- 0261-2194. ; 25:3, s. 212-215
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Tidskriftsartikel (refereegranskat)abstract
- The Iberian Slug, Arion lusitanicus Mabille (Stylomatophora: Arionidae), has developed into a destructive pest in Swedish gardens and orchards over the past 10-20 years. Many attempts to eradicate this pest have been made using a variety of different methods. The aim of this study was to investigate the effectiveness of two different types of homemade traps made from simple, inexpensive materials (plastic PET bottle or an ice-cream box) compared to one type of commercially sold trap (Slugtrap((R)) IT-PAC A B, Sweden) used with bait and beer as attractants. Experiments were carried out on a private property outside Lund, Sweden, over a period of 7 days. The results showed that a homemade trap, i.e. a box trap, can be as efficient as a commercial trap, particularly due to their similar design. In contrast, the homemade bottle trap was not very successful. Additionally, it was discovered that the bait used in the commercial traps did not increase the number of slugs trapped. It was concluded that the beer was the main slug attractant. Ultimately this study suggests a low-cost alternative for small scale to the rather expensive commercially sold traps.
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9. |
- Hultberg, Malin, et al.
(författare)
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Strategies for administration of biosurfactant-producing pseudomonads for biocontrol in closed hydroponic systems
- 2011
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 30, s. 995-999
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Tidskriftsartikel (refereegranskat)abstract
- Zoospore-producing oomycetes are major plant pathogens of particular concern in hydroponic systems. Compared with pesticides, biocontrol using antagonistic microorganisms is a sustainable approach to control oomycetes. Previous research has demonstrated that biosurfactants and biosurfactant-producing microorganisms are potentially useful components of a sustainable biocontrol strategy.In this study three ways of supplying a biosurfactant-producing strain to a recirculating hydroponic cultivation system infected with a zoospore-producing plant pathogen were evaluated. The strain Pseudomonas koreensis 2.74 was added as washed cells, in its spent KB broth or in a minimal medium adapted from the nutrient solution, and compared with control treatments. A significant reduction in disease with up to 50% was achieved when a high concentration of washed cells was added weekly to the plant cultivation system. The disease suppression obtained through addition of washed cells equalled the effect achieved when the purified biosurfactant was used. Phytotoxicity was observed when the spent broth was included in the treatment. (C) 2011 Elsevier Ltd. All rights reserved.
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10. |
- Hysing, Shu-Chin, et al.
(författare)
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Agronomic and economic effects of host resistance vs. fungicide control of barley powdery mildew in southern Sweden
- 2012
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Ingår i: Crop Protection. - : Elsevier BV. - 0261-2194 .- 1873-6904. ; 41, s. 122-127
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Tidskriftsartikel (refereegranskat)abstract
- Agronomic and economic effects of powdery mildew host resistance and a fungicide treatment were investigated in nine ‘Pallas' near-isogenic barley lines. Four years of field trials and virulence surveys detected virulence against all fourteen mildew resistance genes present in the lines. In the field trials, with the exception of gene Mlra, the resistance genes were found to significantly reduce disease severity by 38e99%. The gene mlo5 had a significant negative effect on agronomic characters, while the other resistance genes were neutral. Fungicide treatment reduced powdery mildew by 50e97% and increased grain yield 11e17%, thousand grain weight 6e10%, grain volume weight 2e3% and water content 8e13%, while there was no significant effect on straw strength. From an agronomic perspective, the benefit of the fungicide treatment was greater than that of the selected host resistance. Profitability was directly related to the grain price and cost of fungicide. Net return was negative when using fungicides in years with the lowest grain price, while a higher grain price resulted in a positive net return. It thus seems unprofitable to use fungicides in years with low grain prices, especially when cultivars with effective host resistance are available.
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