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Deficient trace elements concentration in soils, forages, and animals have been reported in several areas of Balkan region. Main challenge in overcoming low productivity of forage and animal production in this region is the lack of data on the nutritional status of the pastures and soils. This study examined the nutrient and pseudo total concentration of trace elements in soil and herbage plants, and the potential deficiency or excess with regards to crop and livestock production. Soil and plant samples from 100 sampling points were collected in the mountainous grasslands of Manjača (between longitudes 16°56′ and 17°8′ east; and latitudes 44°33′ and 44° 42′ north) and Vlašić (between longitudes 17°14′ and 17°29′ east; and latitudes 44°25′ and 44°37′ north). Soil samples were analysed for soil texture, pseudo total concentration (5 ml HNO3) of trace elements (TE), pH, soil organic carbon (SOC), while plant samples were analysed for TE. The soil pH varied from strongly acidic to moderately alkaline. The concentration of SOC varied from 0.5% to 12.3%. Most of the soil samples were finer-textured soils high in silt content. The average concentrations of Na, P, Zn, Se, Cu, Co, and B were low in both soil and herbage plants. Plant K, Ca, Mg, Mo, and Mn concentrations were sufficiently high to meet the requirements of grazing animals, while Fe concentrations was elevated in certain areas. High levels of Mo were found in both soil and plants. The results suggest that imbalances observed in natural pastures of Manjača and Vlašić area, caused by low soil TE concentration and other soil and plant properties, could contribute to poor animal nutrition.

Sammendrag

In order to evaluate the mineral composition of forage crops in respect to dairy cow nutrition 40 soil and corresponding plant (alfalfa, grasses and silage corn) samples were collected from 15 locations in Serbia and analyzed for the concentration of macro- (P, K, and Ca) and microelements (Mn, Cu, Zn, Fe, Co, Se, and Mo). On average, the soils were well provided with the studied elements from the aspect of plant nutrition, but the analyzed fodder crops could not secure suffi cient amounts of Cu, Zn, Se, and Ca for dairy cow nutrition. Principal components analysis was applied in order to determine the connection between the concentrations of macro- and microelements in forage crops and their grouping into components responsible for most of the variability in mineral content. The mineral composition of alfalfa was defi ned by three components (Se, Zn, and Cu) which accounted for the largest part of the established variability. The variability of mineral composition of grasses was defi ned by four components (Zn, K, Se, and P) and that of silage corn by the concentrations of Fe, Mn, and K.

Sammendrag

In Serbia permanent grasslands represent a significant source of animal feed. However, in most regions the animal production and grazing, and thus the productivity and investment in grasslands, are on a very low level. This research aims to analyse impact of nitrogen fertilization and harrowing on lowland permanent grassland (Vojvodina province, Serbia) in order to improve floristic composition and thus yield and quality. Research was carried out during 2012-2015 in Vojvodina province, Serbia, on permanent grassland which was mainly used for sheep grazing. Trial included two nitrogen rates, namely 40 kg ha-1 and 80 kg ha-1, divided on plots with and without harrowing, as well as control treatments. Floristic composition was mostly composed of species from families Poaceace and Asteraceae with a small number and presence of legume species. The number of species changed in the third and fourth years of the trial. Cynodon dactylon L., Lolium perenne L., Festuca sp., were significantly higher on plots with the higher nitrogen rate, while on the control the most frequent spp. were Trifolium campestre Schreb. and Medicago lupulina L. Harrowing, on the other hand, had smaller impact on improvement of permanent grassland.

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Three perennial legumes (alfalfa, red clover and birdsfoot trefoil) and four cool-season perennial grasses (orchardgrass, tall fescue, Italian ryegrass and red fescue) were grown in legume–grass combinations and in pure stands of individual species, at three locations in the West Balkan region (Novi Sad, Banja Luka and Pristina) in the period from 2012 to 2015. The study evaluated dry matter yield, legume–grass–weed proportion and forage quality. High annual forage yield of legume–grass mixtures can be obtained with proper selection of species and an appropriate legume–grass ratio. However, high and stable yield, particularly in the case of grasses, depends on the amount and schedule of precipitation as well as the cutting time. The mixtures and legume pure stands achieved better forage production both per cutting and on the annual basis and had better forage quality than grass pure stands.

Sammendrag

CSNN (current season needle necrosis) gjer stor skade på edelgran til juletre og pyntegrønt både i Europa og USA. Nålene vert misfarga og fell ofte av. Det vi veit om CSNN så langt er: Utbrot av CSNN er truleg klimarelatert Stor variasjon i angrep mellom lokalitetar Genetisk variasjon i resistens mot CSNN CSNN skuldast etter alt å døma ikkje Ca-mangel CSNN smittar frå tre til tre Sydowia polyspora (syn. Kabatina abietis) isolert frå nåler med CSNN-symptom Smitteforsøk med S. polyspora gav CSNN-symptom S. polyspora vart funnen på frø S. polyspora isolert frå nåler med øydelagt vokslag rundt spalteopningane Pestalotiopsis funerea gav ikkje CSNN-symptom Dårleg effekt av kjemiske middel mot CSNN   

Sammendrag

Small plants of nordmann fir (Abies nordmanniana) were grown in chelator-buffered nutrient solution for 31 days. The treatments were arranged in a factorial design with normal and low supply of either Ca or Mg. Fixed free metal activities calculated with Geochem-PC 2.0 (Parker et al. 1995), were obtained in the nutrient solution by addition of HEDTA [N-(2-hydroxyethyl)-ethylenediamine-triacetic acid]. At the end of the experiment, mineral analyses of several elements were obtained from new shoots, roots, old needles and stem. The nutritonal constraints of Ca and Mg significantly affected the mineral composition of the different plant parts. Results will be further reported in the full abstract. The methodology of chelator-buffered nutrient solutions seems appropriate for the study of mineral nutrition to nordmann fir.

Sammendrag

Abstract: A series of experiments were conducted to examine the interactive effects of an organic ligand, a competing cation, and PH on the dissolution of zinc (Zn) from three California soils, Maymen sandy loam, Merced clay, and Yolo clay loam. The concentrations of soluble Zn of the three soils were low in a background solution of Ca(NO3)(2). Citric acid, a common organic ligand found in the rhizosphere, was effective in mobilizing Zn in these soils; its presence enhanced the concentration of Zn in soil solution by citrate forming a complex with Zn. The ability of Zn to form a complex with citric acid in the soil solution was dependent on the concentration of citric acid, PH, and the concentration of the competing cation Ca2+. The PH of the soil solution determined the extent of desorption of Zn in solid phase in the presence of citric acid. The amounts of Zn released from the solid phase were proportional to the concentration of citric acid and inversely proportional to the concentration of Ca(NO3)(2) background solution, which supplied the competing cation Ca2+ for the formation of a complex with citrate. When the soil suspension was spiked with Zn, the adsorption of Zn by the soils was retarded by citric acid via the formation of the soluble Zn-citrate complex. The dissolution of Zn in the presence of citric acid was PH dependent in both adsorption and desorption processes.

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I Norge planlegges og gjennomføres revegeteringstiltak til enhver tid. Mange steder gir standard metoder godt resultat. Ved andre tilsynelatende like steder er resultatet heller dårlig. Det er stor aktivitet og et kreativt mangfold av forskjellige metoder som blir brukt. Vi tror det er et klart behov for et forum for utveksling og sammenligning av erfaringer innen regevegeteringstiltak i Norge, Skandinavia og Europa forøvrig. Denne utgaven av Bioforsk FOKUS samler noen av erfaringene som forskning innen Bioforsk har ført fram til.

Sammendrag

I Norge planlegges og gjennomføres revegeteringstiltak til enhver tid. Mange steder gir standard metoder godt resultat. Ved andre tilsynelatende like steder er resultatet heller dårlig. For spesielle vegetasjonstyper, som for eksempel eksponert kystlynghei som berøres av vindkraftutbygning, finnes det så langt lite erfaring og utviklede metoder. Likevel er det stor aktivitet og et kreativt mangfold av forskjellige metoder som blir brukt. Bioforsk har i de siste 10-årene vært en aktiv aktør for økt forståelse og forvaltning av mange forskjellige økosystemer og landskapstyper. Vi tror det er et klart behov for et forum for utveksling og sammenligning av erfaringer innen regevegeteringstiltak i Norge, Skandinavia og Europa forøvrig. Denne utgaven av Bioforsk FOKUS samler noen av erfaringene som forskning innen Bioforsk har ført fram til.

Sammendrag

Various needle discolorations, often due to lack of uptake of certain nutrients are frequently observed in nordmann fir (Abies nordmanniana) in Norwegian Christmas tree plantations. Most common are the yellow to necrotic needle tips on older needles caused by magnesium (Mg) deficiency (confirmed by chemical analysis of foliage). Even though chemical analysis of soil samples show that Mg is present in sufficient amount, various soil factors may cause Mg-deficiency; too high or too low pH, excess potassium (K) or too wet or too dry conditions. Antagonism, causing imbalance in nutrient uptake, can lead to negative effects. High pH may give Ca2+/Mg2+ antagonism, too low pH NH4+/Mg2+ antagonism, and abundant K K+/Mg2+ antagonism. During wet conditions K+ and other monovalent cations may leave the colloids to regain equilibrium between liquid and solid material. Then Mg2+ may easily bind to the free spaces on the colloids, and thereby becomes unavailable for the plants. If the soil is very dry there may not be enough liquid for the nutrients to be dissolved, and thus uptake inhibited. Nordmann fir is mainly grown in the southwestern coastal region of Norway since the climate there is fairly mild and suitable for this plant species. The yearly rainfall is high in that region, so a main cause for Mg deficiency on nordmann fir is probably related to wet soil conditions. Uptake of Mg after foliage application has proved to be ineffective due to the wax layer on the fir needles. However application on young needles and shoots has been reported by the Norwegian extension service to be successful. K deficiency also results in discoloration of older needles, but symptoms can easily be distinguished from Mg deficiency. Both deficiencies results in yellowing of the needles, but different from K deficiency, the base remains green on needles suffering from Mg deficiency. Both Mg and K are very mobile nutrients in plants, and they are therefore easily translocated from older to younger needles. Samples with yellow discoloration of the youngest needles have been observed to be low in iron (Fe) and manganese (Mn), especially when the trees have grown in soil with high pH. Both nutrients are nearly immobile in plants after they have been transported to the cells, and they are therefore not available for the young shoots. Nitrogen (N) deficiency is seen as a uniform, pale green discolouration of both young and old needles.

Sammendrag

Næringsmangel kan føra til redusert vekst og dårlegare vinterherding, prydverdi og motstandskraft mot ulike skadegjerarar. Ofte er ikkje grunngjødsling nok til å få fram fine tre. Då må ein inn med supplerande gjødsling med ulike næringsstoff. På grunn av vokslag på eldre nåler, vert effektivt opptak av bladgjødsel hindra. Generelt bør difor alle former for bladgjødsling gjennomførast om våren i strekkingsperioden til dei nye skota. I denne perioden er skota mjuke og svært utsette for skade, så ein må vera varsam. I denne artikkelen vert det gitt ei tilråding om grunngjødsling og sett fokusert på symptom på ulike mangelsjukdomar og dei tiltaka som vert tilrådde av Pyntegrøntringen.

Sammendrag

Tilstrekkelig tilgang på mikronæringsstoffer er nødvendig for å sikre avlingsstabilitet og en gunstig mineralsammensetning i plantene. Biologiske, fysiske og kjemiske prosesser i rotsona påvirker frigjøring og binding av mikronæringsstoffer i jorda. Jordanalyser er et viktig verktøy i å evaluere behovet for mikronæringsstoffer. Vanlige jorddata som tekstur og pH i tillegg til jordekstraksjoner gir et bedre bilde på jordas evne til å forsyne plantene med mikronæringsstoffer. Forskjellige kornarter og sorter responderer avlingsmessig ulikt på mangel av mikronæringsstoffer, og har ulik evne til å klare seg der det er lav tilgjengelighet av mikronæringsstoffer.