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.
2023
Forfattere
Dalphy Ondine Camira Harteveld Paul Goedhart Ilse Houwers Jürgen Köhl Peter Frans de Jong Marcel WennekerSammendrag
European canker is one of the most devastating fungal diseases of apple in most temperate regions. The causal agent, Neonectria ditissima, infects trees through wounds in the bark forming cankers that girdle the stem and eventually cause tree death. Timely protection of the trees is challenged by stagnation of symptom expression after infections for a long period of time. The objective of this research is to use a novel TaqMan PCR assay to detect and quantify N. ditissima during the asymptomatic colonization of apple wood. Pruning wounds on branches of the cultivars Elstar and Gala were inoculated with N. ditissima and wood discs were sampled at 2–6, 10–14, and 30–34 mm distance from the inoculation site after 3 hours, 2 weeks, 4 weeks and 8 weeks for the detection and quantification of the pathogen. The TaqMan PCR assay detected N. ditissima in 51% of the inoculated apple tree samples. This was more sensitive than the culturing method detecting N. ditissima in 11% of the samples. An accumulation of N. ditissima DNA up to 34 mm distance from the inoculation site was observed without development of visible symptoms. To our knowledge this is the first time colonization of N. ditissima was detected and quantified in the absence of symptoms of European canker. The implications of this research are discussed.
Forfattere
Anne Muola Traci Birge Marjo Helander Suni Mathew Vili Harazinova Kari Saikkonen Benjamin FuchsSammendrag
Background Cultivation of oilseed rape Brassica napus is pesticide-intensive, and alternative plant protection strategies are needed because both pesticide resistance and legislation narrow the range of effective chemical pesticides. The entomopathogenic fungus Beauveria bassiana is used as a biocontrol agent against various insect pests, but little is known about its endophytic potential and role in plant protection for oilseed rape. First, we studied whether B. bassiana can establish as an endophyte in oilseed rape, following seed inoculation. To evaluate the plant protection potential of endophytic B. bassiana on oilseed rape, we next examined its ability to induce plant metabolite biosynthesis. In another experiment, we tested the effect of seed inoculation on seedling survival in a semi-field experiment. Results Beauveria bassiana endophytically colonized oilseed rape following seed inoculation, and, in addition, natural colonization was also recorded. Maximum colonization rate was 40%, and generally increased with inoculation time. Seed inoculation did not affect the germination probability or growth of oilseed rape, but B. bassiana inoculated seeds germinated more slowly compared to controls. Endophytic colonization of B. bassiana induced biosynthesis of several flavonoids in oilseed rape leaves under controlled conditions. In the experiment conducted in semi-field conditions, inoculated seedlings had slightly higher mortality compared to control seedlings. Conclusion Beauveria bassiana showed endophytic potential on oilseed rape via both natural colonization and seed inoculation, and it induced the biosynthesis of flavonoids. However, its use as an endophyte for plant protection against pests or pathogens for oilseed rape remains unclear. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Forfattere
Suni Anie Mathew Benjamin Fuchs Riitta Nissinen Marjo Helander Pere Puigbò Kari Saikkonen Anne MuolaSammendrag
Aims: In a field study, the effects of treatments of glyphosate-based herbicides (GBHs) in soil, alone and in combination with phosphate fertilizer, were examined on the performance and endophytic microbiota of garden strawberry. Methods and results: The root and leaf endophytic microbiota of garden strawberries grown in GBH-treated and untreated soil, with and without phosphate fertilizer, were analyzed. Next, bioinformatics analysis on the type of 5-enolpyruvylshikimate-3-phosphate synthase enzyme was conducted to assess the potential sensitivity of strawberry-associated bacteria and fungi to glyphosate, and to compare the results with field observations. GBH treatments altered the abundance and/or frequency of several operational taxonomic units (OTUs), especially those of root-associated fungi and bacteria. These changes were partly related to their sensitivity to glyphosate. Still, GBH treatments did not shape the overall community structure of strawberry microbiota or affect plant performance. Phosphate fertilizer increased the abundance of both glyphosate-resistant and glyphosate-sensitive bacterial OTUs, regardless of the GBH treatments. Conclusions: These findings demonstrate that although the overall community structure of strawberry endophytic microbes is not affected by GBH use, some individual taxa are.
Forfattere
Anne MuolaSammendrag
Det er ikke registrert sammendrag
Forfattere
Anne MuolaSammendrag
Det er ikke registrert sammendrag
Forfattere
Anne MuolaSammendrag
Det er ikke registrert sammendrag
Forfattere
M.L. Robinson P.G. Hahn B.D. Inouye N. Underwood S.R. Whitehead K.C. Abbott E.M. Bruna N.I. Cacho L.A. Dyer L. Abdala-Roberts W.J. Allen J.F. Andrade D.F. Angulo D. Anjos D.N. Anstett R. Bagchi S. Bagchi M. Barbosa S. Barrett C.A. Baskett E. Ben-Simchon K.J. Bloodworth J.L. Bronstein Y.M. Buckley K.T. Burghardt C. Bustos-Segura E.S. Calixto R.L. Carvalho B. Castagneyrol M.C. Chiuffo D. Cinoğlu E. Cinto Mejía M.C. Cock R. Cogni O.L. Cope T. Cornelissen D.R. Cortez D.W. Crowder C. Dallstream W. Dáttilo J.K. Davis R.D. Dimarco H.E. Dole I.N. Egbon M. Eisenring A. Ejomah B.D. Elderd Joshua Lynn Anne Muola Vigdis VandvikSammendrag
Interactions between plants and herbivores are central in most ecosystems, but their strength is highly variable. The amount of variability within a system is thought to influence most aspects of plant-herbivore biology, from ecological stability to plant defense evolution. Our understanding of what influences variability, however, is limited by sparse data. We collected standardized surveys of herbivory for 503 plant species at 790 sites across 116° of latitude. With these data, we show that within-population variability in herbivory increases with latitude, decreases with plant size, and is phylogenetically structured. Differences in the magnitude of variability are thus central to how plant-herbivore biology varies across macroscale gradients. We argue that increased focus on interaction variability will advance understanding of patterns of life on Earth.
Forfattere
Anne MuolaSammendrag
Det er ikke registrert sammendrag
Sammendrag
The European spruce bark beetle Ips typographus and the North American spruce beetle Dendroctonus rufipennis cause high mortality of spruces on their native continents. Both species have been inadvertently transported beyond their native ranges. With similar climates and the presence of congeneric spruce hosts in Europe and North America, there is a risk that one or both bark beetle species become established into the non-native continent. There are many challenges that an introduced population of bark beetles would face, but an important prerequisite for establishment is the presence of suitable host trees. We tested the suitability of non-native versus native hosts by exposing cut bolts of Norway spruce (Picea abies), black spruce (Picea mariana) and white spruce (Picea glauca) to beetle attacks in the field in Norway and Canada. We quantified attack density, brood density and reproductive success of I. typographus and D. rufipennis in the three host species. We found that I. typographus attacked white and black spruce at comparable densities to its native host, Norway spruce, and with similar reproductive success in all three host species. In contrast, D. rufipennis strongly preferred to attack white spruce (a native host) but performed better in the novel Norway spruce host than it did in black spruce, a suboptimal native host. Our results suggest that I. typographus will find abundant and highly suitable hosts in North America, while D. rufipennis in Europe may experience reduced reproductive success in Norway spruce.
Forfattere
Hadush Tsehaye Beyene Leif Sundheim Arne Tronsmo May Bente Brurberg Dereje Assefa Anne Marte TronsmoSammendrag
Fusarium verticillioides is the most common fungal pathogen of maize in Ethiopia. Many strains of this pathogen produce fumonisin myotoxins that are harmful to human and animal health. This study was conducted to determine the fumonisin-producing ability of isolates of F. verticillioides isolated from maize kernels collected from different maize- growing areas of the country. Eighty F. verticillioides isolates were grown on autoclaved maize cultures for one month, and the fumonisin content was quantified using Enzyme Linked Immunosorbent Assay (ELISA). All the 80 isolates evaluated were able to produce detectable levels of total fumonisins in the maize culture with values ranging from 0.25 to 38.01 mg of the toxin per kg of culture material (fungal biomass and maize kernels). The mean levels of total fumonisins produced by the F. verticillioides isolates were not significantly (p>0.05) different among maize growing areas, however, the total fumonisins levels produced by isolates obtained from the same area as well as agroecological zones were wide-ranging. The results indicate that the majority (57.5%) of the F. verticillioides isolates associated with maize grains in Ethiopia produced total fumonisins >4 mg/kg, while 35% of the isolates produced total fumonisins <2 mg/kg. The widespread occurrence of higher fumonisin-producing strains across all maize-growing areas in Ethiopia indicates a possible food safety risk. Thus, efforts should be made to prevent the spread of this fungus with good agronomic practices and to implore all possible ways to avoid maize contamination with fumonisin both in the field and in storage.