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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.

NIBIO POP → NIBIO Rapport → NIBIO Bok → Våre poenggivende vitenskapelige publikasjoner →

2011

Forfattere

Eivind Vangdal Sigrid Flatland Ingvild Mehl

Sammendrag

Foliar applications of fertilizers are an important part of standard fertilization programmes in apples to optimize the content of nutrients important to growth and fruit quality. In an experiment in plums (Prunus domestia L.) a foliar fertilization programme was compared to traditional application of fertilizers on the soil. In another experiment extra magnesium, potassium and the combination of both magnesium and potassium were compared to control trees given a standard foliar fertilization programme. Yield and fruit size was registered. Analyses included fruit quality factors, content of major nutrients in fruits and leaves as well as storability. The effects of the different programmes on yield, fruit size and most fruit quality factors were not significant. Fruits from trees given foliar fertilizers had, however, higher content of nitrogen and significantly lower contents of the other major nutrients. The application of extra potassium and magnesium did not increase the level of these elements, but a significant reduction in the Ca-content was observed. Accordingly a higher K:Ca-ratio was observed in potassium and magnesium sprayed fruits. Even though no differences in fruit firmness were observed between the treatments at harvest, after two weeks of storage the plums from potassium sprayed trees were significantly softer than the controls.

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Forfattere

Jan Bartoš Simen Rød Sandve Roland Kölliker David Kopecký Pavla Christelová Štepán Stoces Liv Ostrem Arild Larsen Andrzej Kilian Odd-Arne Rognli Jaroslav Doležel

Sammendrag

Species belonging to the Festuca-Lolium complex are important forage and turf species and as such have been intensively studied. However, their out-crossing nature and limited availability of molecular markers make genetic studies difficult. Here, we report on saturation of F. pratensis and L. multiflorum genetic maps using Diversity Array Technology (DArT) markers and the DArTFest array. 529 and 148 DArT markers were placed on genetic map of L. multiflorum and F. pratensis, respectively, with overlap of 16 markers mapped in both species. The markers were sequenced and mapped in silico to the sequenced genomes of rice and Brachypodium. The utility of the DArTFest array was then tested on a Festulolium population FuRs0357 in an integrated analysis using the DArT marker map positions to study associations between markers and freezing tolerance. Ninety six markers were significantly associated with freezing tolerance and five of these markers were genetically mapped to chromosomes 2, 4 and 7. Three genomic loci associated with freezing tolerance in the FuRs0357 population co-localized with chromosome segments and QTLs previously implicated in freezing tolerance. The present work clearly confirms the potential of the DArTFest array in genetic studies of the Festuca-Lolium complex. The annotated DArTFest array resources could accelerate further studies and improvement of desired traits in Festuca-Lolium species.

Forfattere

Lars Tørres Havstad

Sammendrag

Seed yield of perennial ryegrass normally decrease from the first to the second seed-harvesting year. In order to maintain a high seed yield in the second year crop different treatments in autumn / spring, after harvesting first year crop, were evaluated in two different series with Norwegian tetraploid forage-type cultivars of hybrid- and perennial ryegrass during 2006-2010. Treatments included nitrogen application (both series), treatments of straw (series 1) and regrowth (both series) and spraying against winter diseases (series 2). On average for three trials, straw chopping and spreading during the combining process reduced seed yield with 10 per cent compared to plots where straw had been removed. It is recommended to remove straw soon after harvest and keep stubble height during combining as low as possible. Except for one year (series 2), when the seed crops suffered from an early summer drought (poor utilization of applied spring nitrogen), it was not necessary to apply nitrogen in autumn in order to maximize seed yield. While removal of regrowth in autumn did not normally have any positive influence on the following years seed yield, the highest seed yield in one field was found on plots where regrowth had been cut to 5 cm and removed in early spring. Burning of stubble and regrowth in early spring may harm the plants and should be avoided. Plots being sprayed against winter diseases in late autumn (10 -20 October) produced the highest seed yields in series 2, and was economical beneficial, but further testing is necessary before recommendation for use in practical seed production.

Forfattere

Tor J. Johansen

Sammendrag

Dormancy in a potato tuber prevents sprout growth even under optimal sprouting conditions and is the first stage in the physiological ageing process. The intensity and duration of this phase differs between genotypes (cultivars) and may also be affected by environmental conditions both during tuber bulking and early storage. The current study aimed at finding how simulated high latitude growth conditions influence dormancy and the physiological age of tubers to be used as seed potatoes. In a controlled climate at natural light conditions, tubers grown at a low temperature (9°C) had 2-3 weeks shorter dormancy than tubers grown at higher temperatures (15 and 21°C). In tubers grown at artificial light conditions, day-lengths (12, 18 or 24 h) did not affect dormancy significantly. A post-harvest treatment with a low temperature (one month at 4°C and subsequently 18°C) reduced dormancy by 2-3 weeks in tubers from the highest growth temperatures (15 and 21°C) in comparison with constant 18°C post-harvest. After the lowest growth temperature (9°C) the duration of dormancy was not affected by post-harvest temperature treatments. Physiological age was determined by sprouting characteristics after winter storage. At this stage the sprouting capacity was highest in tubers originating from the lowest and the highest growth temperatures. Further, the number of sprouts per tuber was higher in tubers grown at 9°C than at 15 or 21°C. These results were not correlated with duration of dormancy after the various treatments, suggesting that temperatures may affect dormancy and physiological ageing independently. The present results show that dormancy may be shortened by low grow temperatures, and similarly by low post-harvest temperatures at higher growth temperatures.  

Forfattere

Lillian Øygarden Anne -Grete Buseth Blankenberg

Sammendrag

Pro­sjek­teter fi­nan­si­ert av Nor­ges forsk­nings­råd for pe­ri­oden 2006-2011 og har sommål å bi­stå nor­ske kom­mu­ner i ar­bei­det med å til­pas­se seg eks­trem­værpå kort og lang sikt. Pro­sjek­tet had­de som ho­ved­mål å gjø­re nye forsk­nings­funnsom kan være til hjelp for kom­mu­ner som er ut­satt for eks­trem­vær og ef­fek­terav kli­ma­end­rin­ger. Tre sek­to­rer har hatt spe­si­elt fo­kus: drik­ke­vann,kul­tur­arv og na­tur­mil­jø.   Ef­fek­te­neav kli­ma­end­rin­ger for nor­ske kom­mu­ner er be­skre­vet i rap­por­ten. Dess­utenin­ne­hol­der rap­por­ten et ka­pit­tel om hvor­dan kom­mu­ni­se­re kli­ma­end­rin­gertil kom­mu­ne­ne. Så føl­ger en opp­sum­me­ring av forsk­nings­re­sul­ta­te­nefor de tre ho­ved­sek­to­re­ne. Te­ma­ene in­klu­de­rer av­ren­ning fra jord­bruk,vann­be­hand­lings­an­legg, for­uren­sing som på­vir­ker byg­nings­fa­sa­der,kli­ma­end­rin­ge­nes på­virk­ning på kul­tur­ar­ven og be­slut­nings­ta­king ifor­hold til den­ne og bio­di­ver­si­tet på flom­slet­ter. Et­ter det­te føl­geren dis­ku­sjon om kunn­skap i kom­mu­ne­ne og mu­lig­he­ter for in­te­gre­ringav ny kunn­skap i kom­mu­nal be­slut­nings­ta­king. Til slutt føl­ger et for­slagfor fram­ti­dig forsk­ning på om­rå­de­ne som er dek­ket av det­te pro­sjek­tet.

Forfattere

Inger Hansen Christian Uhlig Odd-Arild Finnes

Sammendrag

The main goal of this study was to develop an alternative bedding material for cattle and sheep based on locally produced woodchips from birch trees and Sphagnum peat in Northern Norway. Four litter mixtures; 2.5 and 5.0 cm woodchips, with and without 20 % peat of total volume were studied in A) Four pens sized 20.4 m2 with two cattle each, ie one pen per treatment; B) Eight pens sized 21.2 m2 with seven ewes each, ie two pens per treatment, and two similar sheep pens with deep straw (barley) as controls. The number of lying animals was counted in 10 minutes’ intervals from 6 pm to 6 am for two consecutive days and the mean number of animals lying simultaneously per pen and hour, was calculated. The cleanliness of the animals was assessed within three separate body sections (legs, side, rear) using a scale from 0-2 points for each body part (0 p=clean, 6 p=dirty). The proportion of animals lying simultaneously per pen and hour and individual cleanliness scores were analysed by GLM. No differences in lying behaviour and cleanliness between the four woodchips mixtures were found, neither for sheep nor cattle. However, straw bedding resulted in the least dirty ewes (P

Forfattere

Christer Magnusson Ricardo Holgado

Sammendrag

Some species of plant parasitic nematodes restrict severely the productivity of crops. In Nordic countries nematodes are often overlooked as factors explaining crop failure. This neglect may relate to a 2/3 reduction of personnel in Nordic nematology which has happened since 1994. The resulting decrease in the lecturing and training of students threatens recruitment, scientific development and awareness of plant nematodes as parasites. This is serious since damage from nematodes can only be reduced by correct management of populations. This will contribute to soil health and a sustainable production. Potato cyst nematode (PCN), Globodera spp., is economically the most important pest attacking potato. It is difficult to detect in the fields, and 20 years may elapse before damage is noticed. The cost for managing PCN is high since management relies on intensive monitoring and regulation. PCN is mainly managed by crop rotations with non-hosts crops grown between alternating susceptible and resistant potato. Among cereal cyst nematodes (CCN) the most common species are Heterodera.avenae and H. filipjevi. Both species have pathotypes differing in their host preferences. Under Nordic conditions serious damage seems to appear with about 40-years intervals. For CCN, correct knowledge of species, pathotype and population density is essential in designing crop rotations. Optimal rotations may allow for yield increases of up to 1 t/ha. In Norway and Sweden damage from root knot nematodes (RKN), Meloidogyne hapla on vegetables and M. naasi on cereals, has been detected more frequently in recent years. RKN have their largest importance in continental and southern Europe, and the increase in field damage seen in the Nordic area may be a first sign of climate change. It is likely that also damage from other nematodes will increase with rising temperatures. Research cooperation between Nordic countries seems urgent to meet the future challenges in plant nematology.

Forfattere

Ricardo Holgado

Sammendrag

  mest avanserte og fremgangsrike planteparasitter. PCN ble påvist i Europa av Kühn i 1881, og i 1923 erklærer Wollenweber den som egen art. Stone i 1973 skiller PCN i to arter. Gul PCN (Globodera rostochiensis) og hvit PCN (G. pallida). I Norge ble PCN først påvist 1955 i Agderfylkene. PCN har spredt seg raskt og i1993 ble de første funn gjort i Nord-Trøndelag. På verdensbasis er PCN funnet utbredt i 23 land og har en begrenset forekomst i 42 land, og i tillegg er det 130 land det ikke er blitt påvist enda. Både gul og hvit PCN er klassifisert som karanteneskadegjørere i 106 respektive 55 land. I de siste årene har PCN blitt påvist i Australia, Canada og USA, som på nytt satt fokus på hvor lett PCN kan spres og hvilke nasjonale konsekvenser PCN har.   De plantesanitære og økonomiske konsekvensene av PCN er betydende. I EU vil PCN bli regulert i det nye EU direktivet 2007/33/EC som implementeres nå. Formålet med direktivet er å bergrense og kontrollere spredningen til PCN. I direktivet gjøres det ingen forskjell mellom gul og hvit PCN, det nevnes at arealer for settepotet og planter til videre dyrking må ha en offisiell dokumentasjon om PCN status, det skal årlig gjennomføres offisiell prøvetaking av 0,5 % av arealet av felt for produksjon av annen potet enn settepotet. Smittede felt får ikke brukes til produksjon av settepotet eller planter til videre dyrking. Bekjempelsestiltak iverksettes på smittede felt som skal brukes til produksjon av annen potet enn settepotet. Ved resistensbryting skal PCN populasjonen rasetestes. Det skal sendes en årsrapport til EU om tiltak som iverksettes i hvert land. I dag benyttes nematicider for å kontrollere PCN, og samtidig disponeres mye resurser for å foredle sorter med resistens.

Forfattere

Ingeborg Klingen Gunnhild Wærsted Karin Westrum

Sammendrag

The two spotted spider mite Tetranychus urticae is known to overwinter as hibernating females, and these partly inactive females may harbour Neozygites floridana. N. floridana is a fungal natural enemy of spider mites. The aim of this study was therefore to investigate whether N. floridana may be present inside living hibernating females of T. urticae throughout the winter season, and if so, in what prevalence and what stage of its fungal life cycle. Hibernating T. urticae females were investigated for the presence of fungal structures throughout one winter (October 12, 2006 to February 19, 2007) in field-grown strawberries in a cold climate in Norway (min. ambient temp -15.3oC). The study confirmed that N. floridana survived the winter as a semilatent hyphal body infection, protected inside live hibernating females. The beneficial fungus N. floridana is therefore ready to develop and sporulate as soon as climatic conditions permits, resulting in early season infection of T. urticae. An early-season infection of N. floridana that may result in the control of T. urticae in strawberries is important, since T. urticae is known to cause reductions in strawberry yield at much lower population levels in early season than in late season. For N. floridana to control T. urticae populations early in the spring, factors important for sporulation and dissemination of the fungus needs to be favoured. The adapted use of pesticides, especially fungicides might therefore be very important at this time of the year.  

Forfattere

Nina Trandem Jørn Haslestad

Sammendrag

  The strawberry blossom weevil (Anthonomus rubi) is a small univoltine weevil severing the flower buds of strawberry and some other species of Rosaceae in order to provide for its offspring. The damage made by the weevil in Norwegian strawberry fields is increasing as chemical control is proving difficult and large numbers of weevils are observed in yet more districts. To develop new strategies to control the weevil, a better understanding of its biology is needed. Most studies of A. rubi have focused on the period when bud damage is done, whilst less is known about the ecology and behaviour at other times of the year. The literature on overwintering habits indicates that in the UK A. rubi leaves the strawberry field to overwinter, while elsewhere in Europe they may stay in the field. In a Norwegian project we used emergence traps and laboratory inspection of individual plants to search for weevils in the late autumn and early spring. In fields with weevil problems, we found significant numbers of A. rubi, typically 1-5 per plant (average of 10 plants) shortly before snow fall, and similar numbers early in the spring. The overall sex ratio was close to 1:1. We also found large numbers of overwintering weevils in plants that had been terminated with glyphosate, indicating that weevils were not repelled by dying plants as overwintering habitat. This considerable presence of weevils in the crop throughout the year could increase the chance of succeeding with alternative methods like microbiological control or mass trapping. It also implies that terminated (glyphosate-treated etc) fields should be ploughed on cool days in the autumn (A. rubi cannot fly at low temperatures) to bury the weevils, and not be left alone till late in the spring for weevils to escape.