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.
2011
Sammendrag
Arable weeds are generally distributed in patches, while herbicides are applied uniformly. Herbicides can be saved if only the patches are sprayed, i.e. patch spraying (PS). Bottlenecks for cost-effective PS are weed monitoring technology and valid technology-based decision rules for PS (thresholds). The novel machine vision algorithm Weedcer has been developed as an efficient weed monitoring tool for PS. Weedcer estimates the proportions of young weed leaves and cereal leaves in high resolution red–green–blue images. We conducted field trials to test relative weed cover (RWC) and relative mayweed cover (RMC) estimated by Weedcer as decision rules for PS. RWC is the total weed cover divided by the total plant cover and RMC is the mayweed cover divided by the total plant cover. The main criterion for evaluation and basis of these thresholds was the measured grain yield. Images (about 0.06-m2) were acquired with a GPS guided autonomous field robot in spring, the normal time for spraying seed-propagated broadleaf weeds in both winter – and spring cereals in Norway. Three map-based trials (weed monitoring and spraying in two separate operations) showed that mean RWC per management unit (12.0 × 12.5-m) was generally adequate. In winter wheat heavily infested with scentless mayweed (Tripleurospermum inodorum (L.) Sch.Bip.) and/or scented mayweed (Matricaria recutita L.), the mean RMC per management unit was more adequate. Progress during the project allowed three additional trials conducted in real-time (weed monitoring and spraying in the same operation). These were conducted with the robot in spring cereals, and showed that a weighted moving average of RWC per image was adequate. The sprayed and unsprayed management units in these trials were minimum 3.0 × 3.0-m and 0.5 × 3.0-m, respectively. Results indicated that the Weedcer-based thresholds should be lower in wheat (Triticum aestivum) than in barley (Hordeum vulgare).
Sammendrag
Sorten Glen Ample dominerer nå norsk bringebærdyrking, også den økologiske. Denne sorten har mange gode egenskaper under norske forhold, men er dessverre spesielt utsatt for store angrep av bringebærbladmidd (Phyllocoptes gracilis) som svekker plantene og går utover bærkvaliteten. Heldigvis fi nnes det økologiske tiltak mot denne skadegjøreren.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Glen Ample is the main raspberry cultivar in Norway. This cultivar is very susceptible to the raspberry leaf and bud mite Phyllocoptes gracilis, and serious damage on both leaves and fruits are common. The only documented control measure available has been fenpyroximate (Ortus/ Danitron), a substance that can only be used once per growing season, which is not sufficient to keep P. gracilis below damaging population levels. Nor can it be used by organic growers. In a search for alternative control measures we conducted trials with rapeseed oil (emulsified with soft soap) and sulphur (Thiovit Jet) in heavily infested fields. The effect was measured by assessing leaf damage and counting mites overwintering in the buds. The results imply that post harvest spraying with vegetable oils or sulphur targeting overwintering females in the buds is a very valuable component of a management strategy for the leaf and bud mite in ‘Glen Ample’.
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.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Artikkelen oppsummerer resultatene fra 8 norske sprøyteforsøk med konvensjonelle og alternative midler mot bringebærbladmidd (Phyllocoptes gracilis) siden 2005. Denne midden er et stort problem i "Glen Ample". To høstsprøytinger med rapsolje+grønnsåpe eller svovel har i forsøkene hatt opp mot 100% effekt på overvintrende bladmidd rundt knoppene. Riktig sprøyteteknikk og god væskemengde er trolig avgjørende for så gode resultater. Når sprøytevæsken renner nedover stengelen og samler seg i restene av bladstilkene rundt neste års knopper, får bladmidden seg et dødelig bad. Ved å kombinere slik høstsprøyting og sprøyting med et vanlig middmiddel i tiden før blomstring bør det være mulig å få bladmidden under kontroll.
Forfattere
Nina TrandemSammendrag
Omtale av bringebærbille og bringebærbladmidd. Stoff om skadedyr i bringebær og bjørnebær ligger på www.bioforsk.no/rubusdyr
Forfattere
Ingeborg KlingenSammendrag
Det er ikke registrert sammendrag