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.
2008
Forfattere
Fykse Haldor Haldor FykseSammendrag
In stockless organic cereal systems undersowing a legume shortly after sowing of cereals is a commonly used practice. Nitrogen supply as well as retarded growth of annual weeds is mentioned as benefits of such use of legumes in cropping systems. There is, however, limited knowledge on the influence of undersown cover crops on the growth of perennial weeds. This issue was addressed in a field experiment (#1) at Ås in South-eastern Norway. Furthermore, a second series of field experiments (#2) aimed at investigating the influence of (i) time of ploughing and (ii) that of black fallow. To obtain a field (#1) with uniform distribution of the perennial weed species, root fragments of Cirsium arvense (L.) Scop. and Sonchus arvensis L. and rhizomes of Elymus repens (L.) Mould., were transplanted by hand in the spring of 2002. The experiment, designed as a split-plot with 3 replicates, was initiated in 2003 and continued until the autumn of 2006. Oat undersown with red clover versus oat alone composed each year the two main plot treatments, except in 2006, in which the whole field was seeded to oat without red clover. Each mean plot was divided into four sub-plots with mechanical treatments in autumn: 1) untreated control; 2) mowing; 3) rotary tilling and 4) shallow ploughing plus harrowing. The autumn treatments were only carried out in 2004 and 2005. The number of weeds was counted at different dates throughout the growing season, and the weed biomass was assessed just before harvest. Preliminary results showed that red clover undersown in oat, compared to oat alone, had limited and in most cases insignificant effects on biomass and number of shoots of all investigated species. No significant interaction between red clover and mechanical treatments in autumn was found. Shallow ploughing suppressed E. repens most, followed by rotary tilling, mowing and untreated, in that order. On S. arvensis, mowing showed the best control, and rotary tilling the poorest. On C. arvense, significant differences between treatments were detected only in 2005, when rotary tilling and shallow ploughing reduced the weed biomass significantly compared to the untreated control.In the second experiment series (#2) C. arvense, S. arvensis and E. repens are subjected to the following treatments: 1) black fallow (soil cultivation) + ploughing in autumn 2) ploughing in autumn 3) spring ploughing, and 4) black fallow + ploughing in spring. Preliminary results from the first experimental year have shown very clear interactions between treatment and weed species: Time of ploughing did not influence the growth of E. repens significantly. On the other hand fallow in autumn suppressed this species more efficiently than fallow in spring. In general, C. arvense and S. arvensis showed the opposite behaviour regarding both time of ploughing and effect of fallow. Spring ploughing, as well as spring fallow, suppressed these species more than treatments in autumn. However, not all comparisons were significantly different. Although the results need more attention as well as new experiments before detailed recommendations can be given, the studies indicate clearly that the effect of different treatments including time of ploughing and soil cultivation periods depends on weed species.
Forfattere
Lars Olav BrandsæterSammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Effects of vegetation and grazing preferences on the quality of alpine dairy products.
Forfattere
Karsten Raulund-Rasmussen Inge Stupak Nicholas Clarke Ingeborg Callesen Helja-Sisko Helmisaari Erik Karltun Iveta Varnagiryte-KabasinskieneSammendrag
Det er ikke registrert sammendrag
Forfattere
Trygve S. Aamlid Mats Larsbo Nick JarvisSammendrag
Water repellency in golf putting greens may induce preferential `finger flow" leading to enhanced leaching of surface applied fungicides. We examined the effects of root zone composition, treatment with a non-ionic surfactant and use of either the fungicide iprodion (3-(3,5-dichlorophenyl)-N-(1-methylethyl)2,4-dioxo-1-imidazoline-carboximide) or a combination of azoxystrobin (Methyl (E)-2-{2-[6-(2-cyanophenoxy) pyrimidin-4-yloxy]phenyl}-3-methoxyacrylate) and propiconazole (1-[[2(2,4-Dichlorophenyl)-4-propyl-1,3-dioxolan-2-yl]methyl]1-H-1,2,4-triazole) on soil water repellency, soil water content distributions, fungicide leaching and turf quality during one year. Soil water repellency was measured both using the water drop penetration time test and tension infiltrometers. Our study was made on a three year old experimental green seeded with creeping bentgrass (Agrostis stolonifera L.) `Penn A-4" at Landvik in SE Norway. The facility consists of 16 lysimeters with two different root zone materials, i) straight sand (1% gravel, 96% sand, 3% silt and clay, 0.4% (w/w) organic matter) (SS), and ii) straight sand mixed with garden compost to an organic matter content of 2.1% (Green Mix (GM)). Results showed that surfactant treatment reduced soil water repellency and the spatial variation in soil water contents. Fungicide leaching was close to zero for the GM lysimeters probably due to stronger sorption. Concentrations in the drainage water from SS lysimeters often exceeded surface water guideline values for all three fungicides, but surfactant treatment dramatically reduced fungicide leaching from these lysimeters. In autumn and winter, surfactant treated plots were more infected with fungal diseases probably because of higher water content in the turfgrass thatch layer.
Forfattere
Grete Lene SerikstadSammendrag
Forskere ved universitetet i Bonn har undersøkt effekten av kompostekstrakt på tomatplanter. Bladgjødsling med slik ekstrakt gav større tomater og mindre angrep av tørråte.
Forfattere
Helge SjursenSammendrag
Einstape tilhører den biologiske gruppen flerårige vandrende med krypende jordstengler, og kan bli 50-150 cm høy. Planten har enkeltstående blad med lange, opprette skaft og store bladplater som er 2-3 ganger finnet. Det er utskilt to underarter: Vanlig einstape har lysgrønne, horisontale blad som gulner tidlig om høsten. Kysteinstape er litt større enn vanlig einstape, og har mørkgrønne, mer opprette blad som holder seg grønne lenge utover høsten. Sporene modnes i juli-august, og spres lett med vinden. Vanlig einstape forekommer i skog, hei og udyrket mark, oftest på basefattig grunn. Kysteinstape forekommer i kysthei og heipreget skog. Begge arter kan være plagsomme ugras i eng og beite, og kan også være en trussel mot øvrige plantearter/biologisk mangfold pga. den sterke konkurransekraften. Planten vrakes vanligvis av husdyrene, men sau eter gjerne unge planter. Bekjempelse: Det anbefales slått omkring midten av juni, og andre slått ca. 6 uker etter første slått, eventuelt sprøyting med ugrasmidlet Gratil 75WG eller Eagle 75WG på vel utviklete blad (ca. 20. juni). Både slått og/eller kjemiske tiltak bør følges opp i flere år.
Forfattere
Trond MæhlumSammendrag
Det er ikke registrert sammendrag
Forfattere
Bjørn FrantzenSammendrag
Foredrag basert på 92 slides