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.
2007
Sammendrag
Denne artikkelen omhandlar biologi og epidemiologi hos både det kjønna og ukjønna stadiet til Mycosphaerella ribis i solbær (Ribes nigrum) og tiltak mot sjukdomen som soppen årsakar.
Forfattere
David M. Gadoury Arne Stensvand Robert C. Seem M. Cathy Heidenreich Maria Herrero Mary Jean WelserSammendrag
Dette foredraget omhandlar det kjønna stadiet til mjøldogg i jordbær, overvintring, spreiing og infeksjon.
Sammendrag
Denne posteren omhandler ontogenetisk resistens mot mjøldog i jordbærplanter.
Forfattere
Matias Pasquali Kye-Yong Seong Jon Menke Erik Lysøe Karen Hilburn Yanhong Dong Jin-Rong Xu H. Corby KistlerSammendrag
To understand trichothecene accumulation and the infection cycle of the head blight pathogen F. graminearum sensu stricto, fungal gene expression profiles were monitored during germination of ascospores and during plant infection. A total of 328 genes were determined to be specifically expressed in ascospores. Among genes highly up-regulated in ascospores was one most closely related to FoStuA of F. oxysporum and StuA in Aspergillus. Mutants deleted for this gene in F. graminearum (FgStuA) are greatly decreased in sporulation and produce no perithecia. Unlike FoStuA mutants in F. oxysporum, FgStuA mutants are greatly reduced in pathogenicity. Reduced pathogenicity may be due to decreased le vels of trichothecene toxins, which in the mutant are
Sammendrag
Occurrence of entomopathogenic nematodes (EPNs) have been reported from all continents in the world except Antarctica. Africa is the continent with fewest reports so far. There have however been reports on EPNs occurrence in Egypt, Kenya and South Africa. EPNs are well known due to their potential as biological control agents of insect pests. Banana weevil (Cosmopolites sordidus) is as an important insect pest of banana. This pest causes reduced banana production in all countries of the East African Highlands in particular Tanzania and Uganda. Different strategies have been employed to control the insect. However the potential for using entomopathogenic nematodes as biological control agents of the weevil has not yet been considered in Tanzania. A preliminary study is ongoing to find out if entomopathogenic nematodes naturally exist in banana growing areas in Tanzania. Currently nine soil samples have been collected from three regions (Mbeya, Morogoro and Coast) with different agroecological conditions. The samples have been taken to Bioforsk in Norway, for extraction of EPNs. Analysis of the samples has been done using larvae of the Greater Wax moth (Galleria mellonella) as bait. After 7 and 14 days dead larvae were removed from the soil samples and placed on water agar. Some of the dead larvae were infected with entomopathogenic fungi and at least one sample had a dead larva with EPN infection. In this sample an adult nematode in the genus Steinernema was isolated. Many dead larvae also had what appeared to be secondary infections of saprophytic nematodes (Rhabditidae) and/or saprophytic fungi. Identification to species or genus level of the nematodes is ongoing. This study reports the find of EPNs for the first time in Tanzania. The isolation of indigenous EPNs are important for further studies on their suitability for control of local insect pests including banana weevils. Future work will include more soil samples for EPNs analysis and semi-field tests using EPNs against banana weevil.
Forfattere
Sverre KobroSammendrag
Seven species of fungivorous thrips, Acanthothrips nodicornis, Bolothrips dentipes, Cryptothrips nigripes, Hoplandrothrips bidens, Phlaeothrips annulipes, Phlaeothrips coriaceus and Xylaplothrips fuliginosus were collected from dead branches of birch. Despite previously being regarded as rare, P. annulipes was abundant in large numbers, but only the first year after the branches had died. Accordingly, P. annulipes perform only one generation on one branch, and have to move to another recently died branch to perform the next.
Forfattere
Richard MeadowSammendrag
The practice of IPM in horticultural crops in Europe in the last half of the 20th century has primarily consisted of fine-tuning the use of pesticides to avoid unnecessary applications. This has led to benefits for growers, consumers and the environment. Many of the fundamental tools for this practice, the synthetic pesticides, are rapidly disappearing from the European market. At the same time, consumers are making clear choices for produce that is not treated with these pesticides. Most of the new pesticides that have appeared in the last decade, and pesticides currently under development, are less effective and/or less long-lasting in the field. These factors have been a driving force in the development of new methods of approaching pest problems in horticultural crops. There is little indication that any method alone will solve pest problems in a cropping situation.
Sammendrag
Numerous fungicide applications are often needed to control powdery mildews in greenhouse-grown crops, and consequently there is an increasing demand for alternative means to control them. In commercial greenhouses, attack of powdery mildew caused by Podosphaera xanthii in cucumbers and P. pannosa in cut roses was controlled by weekly sprays of C-Pro CE601, a dilution of grapefruit seed extract (GSE). The raw material of GSE, delivered by Citricidalâ, is a glycerolic extract from seed and juiceless pulp of grapefruits (Citrus paradise). In both cultures C-Pro at 2000 ppm achieved as good control as treatments with penconazole or triforine. The mean level of attack by powdery mildew on leaves of cut roses one week after the last of three weekly treatments, was 9.8, 12.9 and 40.5 % for penconazole, C-Pro (2000 ppm), and untreated, respectively. In cucumbers, there was less difference between the untreated control and the different treatments, but for all times of assessments, C-Pro and triforine were better than untreated (P = 0.001). There was no significant difference in cucumber between C-Pro and triforine. Phytotoxicity symptoms like leaf twisting and rolling in roses (cv. Jade and Cezann) and dark green leaves and indications of growth retardation in cucumbers (cv. Ventura) were observed at the higher concentrations used (3000-4000 ppm). Thin layer chromatography of C-Pro CE601 has previously shown presence of benzethonium chloride, a synthetic antiseptic agent. Further research is necessary to determine if the observed effects of the product tested are due to natural compounds or if it is merely due to a synthetic preservative agent added. Our results revealed that C-Pro might be a supplement or even a replacement to some of the current fungicides used against powdery mildew.
Forfattere
Trond HofsvangSammendrag
Her gis en oversikt over en del sommerfuglarter som formerer seg lenger sørover i Europa, men som enkelte år migrerer nordover til Norge i store mengder.
Sammendrag
Foredraget presenterer resultater fra forsøk der virkningen av kontinuerlig belysning på fekunditet, utvikling og overlevelse hos veksthusmellus (Trialeurodes vaporariorum) ble undersøkt.