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.
2006
Abstract
I denne rapporten er det vist og drøfta resultat frå ein serie proveniensforsøk med vanleg gran i Sør-Noreg. Formålet med undersøkinga var å prøve om granproveniensar frå Trøndelag og Nordland og høgt over havet på Austlandet og Sørlandet kan gje høgare juletreutbytte i låglandet i Sør-Noreg enn proveniensar som brukast i dag. Forsøksmaterialet omfattar 13 norske proveniensar, der seks var henta nordafjells og sju frå høgareliggjande strok sønnafjells, og dei to proveniensane Cv1 frå Noreg og Harz 7 frå Tyskland som kontrollar. Det var lagt ut eitt forsøksfelt i kommunane Steinkjer, Eid, Bergen, Stord, Hjelmeland, Lindesnes, Stokke og Nes i Akershus. Vurdering av juletrekvalitetar vart gjort ti til tolv vekstsesongar etter såing. På alle tre med høgd ein meter eller større, vart det registrert største trebreidd, tal greiner i øvste krans, tal internodiegreiner på fjorårstoppskotet og spisse greinvinklar, i tillegg til eventuelle skadar og feil. Feltet i Steinkjer fekk omfattande frostskadar dei siste åra og kunne derfor ikkje analyserast for anna enn overleving. Overlevinga var i gjennomsnitt 91 % for alle felt. Gjennomsnittleg juletreutbytte av alle overlevande tre var 55 %, med variasjon frå 33 % i Nes til 71 % i Stokke og Stord. Forskjellar i klima, markslag og topografi på vekseplassane er ein sannsynleg årsak til variasjon i juletreutbytte mellom felt. Feltet i Nes hadde flest tre med skeiv stamme, gankvist og dobbeltopp. Forskjellen i juletreutbytte mellom Stokke og Nes har ei sannsynleg forklaring i aukande frostfare innover i landet. Flyttinga av proveniensar frå nord mot sør og frå høgt over havet gav ikkje større juletreutbytte enn kontrollane. Ulik høgdevekst og ulikt greintal mellom proveniensane har ikkje gitt sikre forskjellar i juletreutbytte. Flytting frå stor høgd over havet til låglandet kan gje dårleg utbytte fordi trea får for dårleg vekst og utvikling. Ved bruk av granproveniensar til juletreplanting, bør dei same proveniensane som er tilrådd for skogproduksjon nyttast. Dette gir betre tryggleik for at trea toler klimaet på veksestaden.
Authors
Astrid JohansenAbstract
Subjektiv, og dermed ulik vurdering av fenologisk utviklingstrinn er årsak til store variasjonar i kjemisk samansetjing og næringsverdi av fôr frå ulike forsøk innom same fôrnummer i Fôrtabellen 2006. • Same forhold kan langt på veg forklare mangelfullt samsvar mellom gras, høy og surfôr av same utgangsmateriale, og likeeins mellom grasslag dyrka i reinbestand og dei same grasslaga dyrka i blanding. • Samansetjing og næringsverdi for ei rekke mindre vanlege fôrslag er basert på ei prøve. • Eksisterande datagrunnlag er tynt med omsyn til fylgjande parametrar for dei fleste fôrslaga: o ulike typar karbohydrat (NDF, totalsukker, vassløyselege sukker, stive) og o ulike protein-fraksjonar (løyseleg protein, potensielt nebrytbart protein, totalt nedbrytbart protein) o nedbrytingskarakteristikkar av NDF • Det vert reist tvil om kvaliteten av NDF-analyser av eldre årgang. • Forsøk med ulike etterbehandlingar (hausteutstyr, konserveringsmiddel, lagring) av same utgangsmateriale har stor innverknad på gjennomsnittsverdiane i Fôrtabellen. • Det vert foreslått å slå saman ei rekke eksisterande fôrnummer slik at talet på fôrnummer kan reduserast • Eksisterande datamateriale for gras, surfôr og høy vert foreslått omgruppert på grunnlag av meltegrad av organisk stoff (FKOS) i fem eller fire (høy) ulike grupper; (svært høg), høg, middels, låg, svært låg meltegrad. • Det er behov for påfyll av nytt datamateriale for fylgjande fôrgrupper: o Beitegrøde/svært tidlege haustetidspunkt av gras o Svært tidleg hausta surfôr av gras og gras/kløver o Raigras av alle slag; Engelsk, italiensk og westerwoldsk o Grønnfôr av erter og korn i reinbestand og blanding • Fylgjande fôrkvalitetar er ikkje representert i Fôrtabellen 2006, men bør vurderast tatt inn: o Surfôr av gjenveksten (2., 3. og 4.slått) av fleirårige engvekstar o Kvitkløver i reinbestand og i blandingar med gras o Sterkt fortørka surfôr (haylage) o Økologisk dyrka fleirårig eng
Abstract
We examined growth responses of Norway spruce using tree-ring series from increment cores and monthly climate variables over the period 19001998. The 1398 cores were selected from 588 plots scattered all over Norway. We correlated tree-ring indices with temperature, precipitation, Palmer drought severity index and length of the growing season.The weather in June had the largest influence on ring widths. However, two different, and almost opposite, response types were found: Tree growth was restricted by June precipitation in the lowlands in southeastern Norway, but by the June temperature in other regions and at high altitudes.In order to define the shift between these two main response types, we correlated response functions with various 30-year mean climatic variables, including humidity and aridity indices. The 30-year mean June temperature was the variable most clearly showing this shift in response, with a threshold at 1213C. At sites with normal temperature below this threshold, spruce responded positively to unusually warm and dry June months, and vice versa.
Authors
Volkmar TimmermannAbstract
Monitoring on the forest officers\" plots in Norway has been running since 1988, with annual assessments carried out by local forest officers. In 2005 they assessed 30277 trees on 557 plots. For 15090 of these trees on 348 plots, there exist complete records of crown condition over the past 18 years. The plots are subjectively selected, mainly in Norway spruce dominated stands, and divided into four development classes. The results from 2005 show a slight increase in mean defoliation of Norway spruce to 16.4 %. There were small, but mostly negative changes in most regions without clear trends in the long term series. In southern Norway, a strong increase in defoliation was observed. Crown colour was improving in the western and northern regions of the country, whereas discolouration was increasing in south-eastern Norway. The mean discolouration was still very low in 2005, with 90 % of the spruce trees having normal, green colour. The mortality rate was low, on the average 3.4 ‰ for all trees. Only few causal agents of crown damage were reported. Data from 18 years of monitoring on the forest officers’ plots reveal some regional patterns for defoliation of spruce in Norway, with western Norway having the lowest mean defoliation through all years, and Mid-Norway the highest. In the other regions, the trends are not so clear with greater fluctuations in defoliation and discolouration.
Abstract
To avoid problems with seed borne diseases in organic cereal production, seed health testing should be compulsory in certification of organic seed. In general, significantly lower infection frequencies of seed borne diseases are recorded on seedlings than on seed. Thresholds for the amount of seed borne inoculum that can be accepted for organic production are therefore needed. The aim of the work presented is to compare transmission rates of Drechslera on barley and oats under organic and conventional conditions, to be able to decide if existing thresholds used to assess the need of chemical seed treatment, can be applied for acceptance of organic seed lots, or for recommendation of alternative treatments. Field experiments were carried out in 2005 in conventional and organic fields situated close to each other at each of three locations (south/east-Norway, east-Norway and mid-Norway). 10 seed lots of barley and 10 lots of oats, with a range of seed infections (barley: 0-94 % Drechslera teres, average 23,7 %; oats: 0-66 % Drechslera avenae, average 22,0 %) were planted in rows of 100 seeds with 8 replicates in each location/`growing system". Percent emergence and seedlings with primary infections were recorded at BBCH 12-13. In average of the three locations 2,5 % and 2.1 % barley seedlings were infected when grown in conventional and organic fields, respectively. In oats, 2,0 % and 0,8 % infected seedlings were recorded in conventional and organic fields, respectively. Similar experiments will be carried out in 2006 and results from this will also be presented.
Abstract
The aim of this three-year study (2001"2003) was to optimize fungicide application against anthracnose (Colletotrichum acutatum) in sweet and sour cherry orchards. The experimental sprays were applied to trees receiving normal fungicide programmes (grower schedule), although without the use of dithianon, except for the first year where only the experimental applications were applied to the sour cherry trees. Fungicide treatments were applied with either dithianon or copperoxychloride added prior to flowering or with dithianon added after flowering. Spraying with dithianon or copperoxychloride prior to flowering did not significantly reduce anthracnose compared to untreated. Two applications with dithianon during the green fruit stage (from petal fall and during the following 3"4 weeks) greatly reduced anthracnose at harvest. Three applications on green fruit did not reduce disease more than two applications. In sweet cherries, two sprays with dithianon at the green fruit stage in addition to the grower schedule reduced anthracnose at harvest from 14% to 3% in 2002 and from 15% to 1% the following year. In 2001, when very few fruit developed anthracnose, no treatment effects were evident. Treatments on green sour cherry fruit similar to those on sweet cherries reduced the attack of anthracnose from 85% to 42% in 2002 and from 51% to 12% the following year. In 2001, no treatment included only sprays on green fruit. However, one treatment, which included copperoxychloride at bud burst, one application of dithianon during flowering and two applications on green fruits, reduced anthracnose from 27% to 9%. Based on these results, cherry growers are recommended to spray twice with dithianon on green fruit if they have a history of anthracnose in their orchards.
Abstract
Korncystenematoder (Heterodera spp.) er et kompleks av arter og patotyper. Så langt er det i Norge påvist den vanlige havrecystenematoden (Heterodera avenae) patotype Ha 11, H. avenae svensk patotype ”Våxtorp” og rugcystenematoden (H. filipjevi) svensk patotype ”Vest”. Biotest med disse patotypene ble gjennomført i 2004 og 2005 ved Sveriges Lantbruksuniversitet i Alnarp. Tester i veksthus av 63 kornsorter viste at de fleste sortene i testen var mottakelige for Ha 11 og Ha Våxtorp. Dette var også tilfelle i tester med H. filipjevi Vest for sorter av bygg og vårhvete, mens et flertall av havresortene var mer eller mindre resistente. Resultatene viser også at det finnes flere sorter på det norske markedet som kan benyttes for å holde korncystenematodene på et lavt nivå. I bygg var Frisko, Helium Meltan, Otira og Simba resistente mot Ha 11. For Ha Våxtorp viste ingen av de testede sortene seg å være resistente. Byggsortene Antaria, Frisko, Gunilla, Iver, Pernilla og Sunnita var resistente mot H. filipjevi Vest. I havre viste sortene Sanna, Gunhild og Vital resistens mot Ha 11, og mot Ha Våxtorp var sortene Gunhild, NK98059, Sanna og Vital resistente. Mot H. filipjevi Vest var Bikini, Bessin, Gunhild, Kerstin, Liberto, Matilda, NK 98008, NK980591, Olram, Pol, Sanna, SW 98195 og Vital resistente.
Authors
May Sæthre Arne Hermansen Ragnhild NærstadAbstract
The western flower thrips, Frankliniella occidentalis (Pergande), is a highly polyphagous species with a host range including over 250 species of herbaceous and woody plants belonging to 62 families. F. occidentalis originates in western USA but has spread, since 1970, into many countries in Asia, Africa, Central and South America, Europe and Oceania. In southern regions of Europe the pest is found outdoors attacking the flowers of a number of host plants. In northern European countries it is a pest mainly in protected crops (i.e. glasshouses) attacking a number of ornamentals and vegetables. F. occidentalis is a vector of Tomato spotted wilt virus (TSWV) and several other viruses. Both these organisms are regulated as quarantine pests in the EPPO region (European and Mediterranean Plant Protection Organization). The first report of F. occidentalis in Norway was in 1986 and it spread very quickly within greenhouse environments. In 1987 the species was added to the A-list (quarantine pests with zero-tolerance on import to Norway) and a comprehensive spraying program to eradicate the introduced pest and stop further spread was developed. The thrips, however, continued to spread and in 1991 about 40% of all greenhouses in Norway were infested with F. occidentalis. A plan of action (Trips-aksjonen) to combat and eradicate F. occidentalis from Norway was executed in 1991. In spite of extensive efforts by growers and authorities they did not succeed in eradicating or stopping further spread of F. occidentalis. In 1997 the species was considered established in Norwegian greenhouses and it was therefore deleted from the Norwegian A-list. It is now under surveillance as a vector for TSWV (an A-list pest) and is treated as a quarantine pest if discovered in connection with TSWV. The introduction and establishment of F. occidentalis in Norwegian greenhouses has been a burden to both growers and the society. Growers have suffered financial losses in terms of costs of carrying out comprehensive quarantine instructions (1986-1996) as well as through direct crop loss and costs of control measures (1986-2006). Indirect economic impacts of F. occidentalis include the implications for growers due to the quarantine instructions (1987- 1996) such as increased labour to carry out the instructions; cost of pesticides; loss of production time during the quarantine and eradication period; loss of contracts when not able to deliver plants and seedlings on time; loss of reputation; and perhaps as a combination of the others also loss of future contracts. Growers have also suffered in terms of health risks as they have used pesticides more frequently and thereby been exposed to pesticides more often. Very rough estimates and assessments to predict potential crop loss caused by F. occidentalis suggests a worst case scenario (or 100% crop loss) to be about 1454.4 mill NOK per year (2003-numbers). Assuming that the proportion of infested greenhouses at any given time during the year is somewhere between 30-40%, then potential crop losses would be between 436-582 mill NOK per year. It should be underlined that these numbers are rough estimates only, not accurate measurements. Introduction/establishment of the species has resulted in an increased effort from extension service, phytosanitary authorities, and scientists, the costs involved are, however, difficult to assess. […]
Authors
Aldo Marchetto Rosario Mosello Gabriele A. Tartari John Derome Kirsti Derome Pia Sorsa Nils König Nicholas Clarke Erwin Ulrich Anna KowalskaAbstract
Working Ring Test (WRT) was organised in the framework of the EU Regulation (EC) No 2152/2003 (`Forest Focus`) and of the UN/ECE Program `ICP Forests` in order to evaluate the overall performance of the laboratories monitoring atmospheric deposition and soil solution in European Forests, and to verify the improvement in the analytical quality as the results of the QA/QC work carried out in the laboratories which participated to a previous WRT. Seven natural samples of atmospheric deposition and soil solutions and 5 synthetic solutions were distributed to 52 laboratories, which analysed them using their routine method for the following variables: pH, conductivity, calcium, magnesium, sodium, potassium, ammonium, sulphate, nitrate, chloride, total alkalinity, phosphate, total dissolved nitrogen, dissolved organic carbon, aluminium, copper, iron, manganese, zinc, total phosphorus, total sulphur and silica. For each variable, a Data Quality Objective was defined, based on the results of the previous WRT, the comparison with the DQOs of other international networks, and the importance of the variable in deposition and soil solution monitoring. It resulted that 38% of the results do not meet the DQO, showing for which variables and in which laboratories improvement in analytical performance is needed. The results of the exercise clearly show that the use of data check procedures, as those described in the ICP Forests manual for sampling and analysis of atmospheric deposition, would make it possible to detect the presence of outliers or results not accurate, and would greatly improve the overall performance of the laboratories. Some analytical methods were found not suitable to the samples used in this WRT, nor to atmospheric deposition samples in European forests, and they include outdated methods, such as turbidimetry or nephelometry for the determination of sulphate, silver nitrate titration and ion selective electrode for chloride, Kjeldahl digestion for the determination of ammonium and organic nitrogen, and colorimetric titrations for alkalinity. A detailed discussion of the analyses of total dissolved nitrogen, dissolved organic carbon and total alkalinity is also provided, as they were the variables for which more analytical difficulty arose. Finally, a comparison between the results of this WRT and those of the previous exercise showed that the analytical performance of the laboratories participating in both WRTs improved as a consequence of the adoption of QA/QC procedures.
Abstract
Three multiparous cannulated dairy cows were used to test the effect of including 0, 23 % and 46 % red clover (RC) on dry matter (DM) basis in timothy (T) silage on nitrogen (N) intake, utilization and excretion. The cows were offered a fixed ration; 13 kg silage and 7 kg concentrate DM. The N intake and urine N excretion increased with increasing silage clover proportion. Milk yield was higher in the clover containing silages than in the pure grass silage, probably due to higher organic matter digestibility in RC containing silages. The efficiency in converting feed N into milk N, however, was higher in cows fed the timothy silage than in cows offered grass/clover silages. The efficiency in microbial protein synthesis in the rumen and the proportion of microbial N of the total N flow to duodenum was higher on the T diet than on the RC containing diets. However, the clover diets gave a slightly higher proportion of bypass N originating from the feed. So, the total flow of N to duodenum was the same for all three diets. In conclusion, increased proportion of RC in T silage did not improve the N utilization.