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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

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Abstract

Horse owners may lack knowledge about natural thermoregulation mechanisms in horses. Horses are managed intensively; usually stabled at night and turned out during the day. Some are clipped and many wear a blanket, practices which reduce the horse's ability to regulate heat dissipation. The aim of this study was to investigate the relationship between hair coat characteristics, body condition and infrared surface temperatures from different body parts of horses. Under standard conditions, the body surface temperature of 21 adult horses were investigated using infrared thermography. From several readings on the same body part, a mean temperature was calculated for each body part per horse. Detailed information on horse breed, age, management and body condition was collected. Hair coat samples were also taken for analyses. A mixed statistical model was applied. Warmblood horse types (WB) had lower hair coat sample weights and shorter hair length than coldblood horse types (CB). The highest radiant surface temperatures were found at the chest 22.5 ± 0.9 °C and shoulders 20.4 ± 1.1 °C and WB horses had significantly higher surface temperatures than CB horses on the rump (P < 0.05). Horses with a higher hair coat sample weight had a lower surface temperature (P < 0.001) and hind hooves with iron shoes had a significant lower surface temperature than unshod hind hooves (P = 0.03). In conclusion, individual assessment of radiant surface temperature using infrared thermography might be a promising tool to gather data on heat loss from the horses' body. Such data may be important for management advice, as the results showed individual differences in hair coat characteristics and body condition in horses of similar breeds.

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Abstract

Dollar spot was officially documented in Scandinavia in 2013 and the spread and damage from this disease has increased during last years. In summer 2017, on the golf greens with red fescue (Vallda GC, Sweden) and with the mixture of red fescue, colonial bentgrass and annual bluegrass (Roskilde GC, Denmark) rolling 2 times per week reduced dollar spot 61% and 37% and rolling 4 times per week reduced dollar spot 95% and 54%, respectively. Thus, rolling 3-4 times per week can be recommended on golf greens with dollar spot pressure. In the experiment 2018 dollar spot was reduced 24% with increase in nitrogen from 150 to 240 kg ha-1 yr-1 on creeping bentgrass/annual bluegrass golf green (Kävlinge GK, Sweden). However, the increased N-rate lead to a higher degree Microdochium patch from 14% to 30%.

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Abstract

The major part of Norwegian apples is marketed within 3-4 months after harvest. ‘Summerred’ is a popular medium early cultivar in Norway, however, it is known to soften quickly during storage and marketing. Storing apples in low temperature and low oxygen atmosphere will slow down the ripening and the fruit will keep green and firm. Delayed cooling has been reported to reduce susceptibility to develop physiological disorders like scald. The experiment included different strategies in delaying cooling (5 days at 7°C) and allowing the apples to reach 1 kPa oxygen storage after an intermediate period (5 days) at 3 kPa oxygen. The main focus was on changes in firmness, degreening, scald and fruit rots. The apples were stored for 3, 6 or 9 weeks in 1 or 4°C and analyzed for standard fruit quality factors (color, firmness, IAD-index, starch, soluble solids content and titratable acidity) as the samples were removed from low temperature and low oxygen storage and after a week at 20°C in regular atmosphere (shelf life). Physiological disorders and fruit rots were registered. In these experiments the fruit quality changes were greater (poorer quality) in apples kept at 7°C for 5 days before storage at 1 or 4°C compared to apples stored immediately at low temperature. The intermediate storage in 3 kPa oxygen tended to make the apples keep firmer during storage. The stepwise reduction in oxygen content reduced the negative effect of delayed cooling. Delayed cooling slowed the starch degradation. The incidences of soft scald and fruit rots were low, and the effects of delayed cooling and/or delayed low oxygen storage were weak.

Abstract

BACKGROUND Low growth temperatures and the special light qualities of midnight sun in northern Scandinavia, have both been shown to improve eating quality of swede root bulbs. To study the combined effect of these factors on root development and sensory‐related compounds, plants were grown in phytotron under different 24 h supplemental light‐emitting diode (LED) light colours, at constant 15 °C, or reduced end‐of‐season temperature at 9 °C. RESULTS Far‐red LED (740 nm) light induced longer leaves and produced more roundly shaped bulbs, than the other light quality treatments. At constant 15 °C, supplemental light of far‐red LED also produced a stronger purple crown skin colour than the other LED treatments. This difference between light quality treatments disappeared at 9 °C, as all bulb crowns developed a purple colour. There were no significant effects of LED‐supplements on sugar concentrations, while the reduced temperature on average did increase concentrations of d‐fructose and d‐glucose. Total glucosinolate concentrations were not different among treatments, although the most abundant glucosinolate, progoitrin, on average was present in highest concentration under LEDs containing far‐red light, and in lower concentration at 9 °C compared to 15 °C. CONCLUSION The light quality of 24 h photoperiods in combination with temperature appears primarily important for growth and morphological traits in swede root bulbs. Influence of light quality and low temperature on appearance and sensory‐related compounds may be utilized in marketing of root vegetables with special quality related to growth conditions of high latitude origin. © 2020 Society of Chemical Industry

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Abstract

Agricultural practices to improve yields in small‐scale farms in Africa usually focus on improving growing conditions for the crops by applying fertilizers, irrigation, and/or pesticides. This may, however, have limited effect on yield if the availability of effective pollinators is too low. In this study, we established an experiment to test whether soil fertility, soil moisture, and/or pollination was limiting watermelon (Citrullus lanatus) yields in Northern Tanzania. We subjected the experimental field to common farming practices while we treated selected plants with extrafertilizer applications, increased irrigation and/or extra pollination in a three‐way factorial experiment. One week before harvest, we assessed yield from each plant, quantified as the number of mature fruits and their weights. We also assessed fruit shape since this may affect the market price. For the first fruit ripening on each plant, we also assessed sugar content (brix) and flesh color as measures of fruit quality for human consumption. Extra pollination significantly increased the probability of a plant producing a second fruit of a size the farmer could sell at the market, and also the fruit sugar content, whereas additional fertilizer applications or increased irrigation did not improve yields. In addition, we did not find significant effects of increased fertilizer or watering on fruit sugar, weight, or color. We concluded that, insufficient pollination is limiting watermelon yields in our experiment and we suggest that this may be a common situation in sub‐Saharan Africa. It is therefore critically important that small‐scale farmers understand the role of pollinators and understand their importance for agricultural production. Agricultural policies to improve yields in developing countries should therefore also include measures to improve pollination services by giving education and advisory services to farmers on how to develop pollinator‐friendly habitats in agricultural landscapes.

Abstract

Several scientific groups have concluded that the use of biochar as an on-farm management tool for carbon sequestration should be further investigated. Review articles also pinpoint the use of biochar to reduce greenhouse gas emissions from the entire agricultural production, and this should be studied using whole-chain models. Biochar is added to animal diets with the main purpose of enhancing animal health. There are indications that biochar fed to ruminants may reduce enteric methane emission. Twenty-four ewe lambs were fed one of two diets, a control diet (no biochar) and a biochar diet (1.4% biochar). There were no differences in dry matter intake and average daily growth rate between animals. An expected reduction in enteric methane emissions from animals fed the biochar diet was not detected. We conclude that the effect on enteric methane emissions may depend on structure and properties of the biochar offered. We suggest further research on biomass and pyrolysis of biochar to accommodate several properties as a feed additive for farm animals.