Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2010
Authors
Margarita Novoa Garrido Harald VoldenAbstract
The main objective of this experiment was to compare timothy and X-Festulolium varieties Felina and Felopa as forage for growing bulls. Thirty one-year-old Norwegian Red bulls were assigned to one of the three feeding groups by stratified block randomisation within weight in individual boxes and feeding. The forage was grown at Bioforsk"s research station in Bodø, (latitude: 67.28 °N), Norway, and harvested at a NDF content of 500 g/kg dry matter in the summer of 2008. The grass was ensiled in round balls and fed ad libitum. The bulls were fed a fixed amount of one kg of concentrate/day through the experiment. Animals were slaughtered at a live weight of 600 kg, and the slaughters were classified according to the EUROP system. The animals fed with timothy had an overall larger weight gain than the bulls fed with the X-Festulolium variants, though the weight gain decreased towards the end of the feeding period. The forage consumption in the timothy group was also larger. Grass type had no effect on the on the classification of the slaughters.
Authors
Trond MæhlumAbstract
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Abstract
An analysis of discharge from agricultural catchments in Norway, Estonia and Latvia showed that information on extreme events can be lost when considering average daily discharge values. This might have serious implications for design purposes as well as for analysing nutrient - and soil loss processes. Inclusion of higher time resolution is proposed
Abstract
The Skuterud catchment is a small artificially drained agricultural catchment, located in south eastern Norway. The total area of the catchment is 4.5 km2 of which agriculture covers 2.7 km2, forest 1.3 km2 while the rest is occupied by urban area. The main agricultural crops are wheat, barley and oat. The climate is cold temperate continental or subarctic with a winter season, lasting from November -March and characterized by periods with below-zero temperatures and a varying degree of snow cover, interchanged with thaw periods combined with precipitation and runoff. In Norway, melt water, causing surface runoff, is one of the most serious reasons for erosion, in addition to near-saturated soil moisture conditions after longer periods with rainfall during the autumn. Climate change can potentially lead to an increase in the number of freeze/thaw cycles which in addition to the predicted increase in precipitation during the period after the growing season from September - April, might lead to an increase in both the amount of runoff and its intensity, with subsequent adverse effects on erosion and nutrient loss. Models are indispensable tools in the prediction of climate change effects on runoff generation. In this respect, the Drainmod model has been tested on the Skuterud catchment concerning its ability to predict runoff from an artificially drained agricultural catchment under prevailing winter conditions. The results are presented in this paper. If proven successful, the model can be used to predict the long term hydrologic impacts of climate change for the Norwegian conditions
Abstract
It is well known that farming practices, soil type, topography and climatological conditions are important factors in nutrient loss generation from agricultural dominated catchment. Catchments having a large contribution of groundwater runoff in the total runoff, in general had lower nitrogen losses. Other studies have shown that longer residence times in the Baltic catchments partly could explain the lower nitrogen loss compared to Norwegian catchments. Also catchment scale might play an important role in nutrient loss processes. Artificial drainage of agricultural land can lead to an increase in nitrate-nitrogen runoff.
Authors
Christian Linder Janet Allen Catherine Baroffio Agata Broniarek-Niemiec Victorio Brookes Jerry Cross Cathy Eckert Rudolf Faby Bruno Gobin Alberto Grassi Adrian Harris Barbara Labanowska Emilie Lascaux Carlo Malavolta Vincent Michel Slobodan Milenkovic Thilda Nilsson Paivi Parikka Klaus Paaske Jean-Jacques Pommier Daniel Prodorutti Lene Sigsgaard Arne Stensvand Christer Torneus Nina Trandem Tuomo Tuovinen Gabor VetekAbstract
The usage of plant protection products and biocontrol agents in soft fruit production has always been an important subject for the IOBC/WPRS Working Group "Integrated Protection of Fruit Crops" Study Group "Soft Fruits". The usage of pesticides and biological control methods varies considerably between countries and it is very difficult to get a good overview on the range of products that are applied or in development in soft fruits. In order to share and facilitate the flow of information, the Study Group "Soft Fruit" initiated a survey on the availability and usage of active ingredients and biocontrol agents in the different European countries in 2007. First, the most important pests and diseases in strawberry and raspberry production were identified. Then members of the different countries listed available products on the domestic market and indicated their usage in the field. So far 15 countries have contributed to the survey. The received data are accessible on the website http://www.any3.ch/IOBC/Softpest/index.html
Abstract
Most fungicide applications targeting apple scab aim to control primary infections caused by ascospores and spraying is thereby linked to ascospore availability. We investigated the effect of pre bud break climatic conditions on seasonal patterns of ascospore release. Apple leaves bearing pseudothecia of Venturia inaequalis were overwintered at orchard sites in 8 countries for up to 3 years. Leaf samples were collected 2 to 5 weeks before bud break and again at bud break, air dried, and sent via airmail to Norway. The samples were stored at -18ºC upon arrival until tested. Disks cut from each replicate leaf sample were incubated moist at 20ºC to allow ascospore maturation but prevent discharge. Matured ascospores were induced to discharge twice a week and enumerated until the supply was exhausted. The proportion of ascospores ejected was fitted against degree-day accumulation using logistic regression. The regression intercept (onset maturation), slope (maturation rate), as well as the absolute number of spores counted differed significantly (P< 0.001, P = 0.05, P< 0.001 respectively) among sites and sampling dates. There was a significant interaction between site and sampling date, indicating that climatic conditions prior to bud break differentially impacted the subsequent ascospore availability. Observed differences could perhaps be used to further refine previously described models of ascospore maturity.
Authors
David M Gadoury Arne Stensvand Robert C. Seem Catherine Heidenreich Maria Herrero Mary Jean Welser Andrew Dobson Håvard Eikemo Belachew AsalfAbstract
Cleistothecia on leaves of deciduous perennials are often dispersed before leaf fall to other substrates. In contrast, strawberry leaves remain attached during winter, and cleistothecia of Podosphaera macularis remained attached to these leaves. Release of overwintered ascospores was coincident with renewed plant growth, and pathogenicity of ascospores was confirmed. Upper and lower surfaces of emergent leaves were similarly susceptible, but upper surfaces were obscured by folding in emergent leaves. Emergent leaves exposed to airborne inoculum developed severe infection of the lower surface, but not the obscured upper surface. Emergent leaves acquired ontogenic resistance during unfolding, and the upper leaf surface thereby escaped infection. We found no evidence that the pathogen survives winters in New York, USA or Norway within crown tissue. Plants stripped of infected leaves remained mildew-free when forced after overwintering, while mildew colonies commonly developed on emergent leaves of plants not stripped of mildewed leaves. Unsprayed plots established using mildew-free plants either remained asymptomatic or developed only traces of powdery mildew during one growing season, even when located within 100 to 150 meters of severely diseased plots. In summary, our results suggest the following: (i) sanitation, use of disease-free plants, and eradicative treatments could contribute greatly to management of strawberry powdery mildew; (ii) cleistothecia represent a functional source of primary inoculum; and (iii) the common observation of higher mildew severity on lower leaf surfaces may reflect escape of the upper epidermis due to the combined effect of leaf folding and rapid acquisition of ontogenic resistance.
Abstract
Colletotrichum acutatum causes bitter rot (often named anthracnose) in cherry and apple. It is the most important fruit decay in sour cherry in Norway and may give severe losses also in sweet cherry and apple. We have found the fungus in all fruit and berry crops grown commercially in the country and on many ornamentals and a few weeds. Single spore isolates frequently developed the ascigerous stage of the fungus (Glomerella acutata) in culture, but it was not detected on apple or cherry plant material. If still attached to the tree, fruits and fruit stalks of sour cherry infected the previous year produced conidial inoculum throughout the entire following season. Also newly infected sour cherry flowers produced conidial inoculum until harvest. Up to 80% of the fruit spurs on sweet cherry had buds infected with C. acutatum in spring. Apple buds also contained the fungus, but to a much lower extent. More than 90% of the sweet cherry leaves could be infected with C. acutatum around harvest in heavily infected orchards. Symptoms on leaves never appeared in the orchards. We also found such asymptomatic leaf infections in apples. Most of the inoculum seemed to be present on the fruit trees themselves. However, initial inoculum in newly established, disease free plantings may be introduced from older fruit trees, ornamentals and weeds in or in close vicinity to the orchards.
Abstract
In Norway, organic apple growers only have sulphur available as a fungicide. When organically grown apples are stored, growers must thus rely entirely on alternative means to reduce the amount of storage decay. It is known that harvest time and calcium content may affect fruit rots in apple. The effect of harvest time on storage decay was assessed during three years. After storage there was a clear increase in fruit decay from the earliest to the latest picking times, both recorded as total decay and for the important storage diseases bitter rot (caused by Colletotrichum acutatum) and lenticell rot (caused by either Phlyctaena vagabunda or Cryptosporiopsis curvispora). In mean of three years apples of cv. Aroma harvested 2 or 1 week prior to normal harvest time, at normal harvest or 1 or 2 weeks afterwards and stored for three months in a ventilated cold store, had 6, 14, 35, 33, and 35% bitter rot, respectively. Similar numbers for lenticell rot (in mean of two years) were 6, 10, 11, 16 and 24%, respectively. Applications of calcium at different times prior to harvest reduced the amount of storage decay in some trials, but not consistently.