Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2023
Authors
Taavi Riit Michelle Cleary Kalev Adamson Mimmi Blomquist Daiva Burokienė Diana Marčiulynienė Jonàs Oliva Anna Poimala Miguel Angel Redondo Gunn Strømeng Venche Talgø Leho Tedersoo Iben Margrete Thomsen Anne Uimari Johanna Witzell Rein DrenkhanAbstract
This study aimed to determine the differences and drivers of oomycete diversity and community composition in alder- and birch-dominated park and natural forest soils of the Fennoscandian and Baltic countries of Estonia, Finland, Lithuania, Norway, and Sweden. For this, we sequenced libraries of PCR products generated from the DNA of 111 soil samples collected across a climate gradient using oomycete-specific primers on a PacBio high-throughput sequencing platform. We found that oomycete communities are most affected by temperature seasonality, annual mean temperature, and mean temperature of the warmest quarter. Differences in composition were partly explained by the higher diversity of Saprolegniales in Sweden and Norway, as both total oomycete and Saprolegniales richness decreased significantly at higher longitudes, potentially indicating the preference of this group of oomycetes for a more temperate maritime climate. None of the evaluated climatic variables significantly affected the richness of Pythiales or Peronosporales. Interestingly, the relative abundance and richness of Pythiales was higher at urban sites compared to forest sites, whereas the opposite was true for Saprolegniales. Additionally, this is the first report of Phytophthora gallica and P. plurivora in Estonia. Our results indicate that the composition of oomycetes in soils is strongly influenced by climatic factors, and, therefore, changes in climate conditions associated with global warming may have the potential to significantly alter the distribution range of these microbes, which comprise many important pathogens of plants.
Authors
Stefano PulitiAbstract
No abstract has been registered
Authors
Michel VerheulAbstract
No abstract has been registered
Abstract
Temperature and humidity were measured in 28 vegetable stores and corelated to quality of stored vegetable through two storage seasons. The vegetables swede, carrot and celeriac were grown at one site within each of the four regions in Norway ROG, MID, INN and OSL, respectively. After harvesting, the vegetables were weighed and visually assessed for any injuries or diseases and stored in different stores within the same region as grown. Four bags dug down in four storage bins in each store. Temperature and humidity were logged in each bag as well as on the top of each bin and on wall of the storage. In general, we found significant differences in the storage quality between the different storages as well as between regions. Correlating data on quality with temperature data shows for carrot a tendency to an increase in the proportion of fresh roots and reduction in incidence of tip-rot by an increased average temperature during the first two weeks of storage. This corresponds to results from tested various wound healing treatments. An increase in accumulated temperature during the storage period showed a tendency to increase the emergence of tip-rot and reduce the proportion of fresh roots. For celeriac, the effect of temperature varied between years, possibly due to a large difference in quality in the two test years, and it was difficult to draw any conclusion. In swede, the results suggest that a decrease in temperature in the first two weeks of storage increased the risk of the symptom shown as black veins in the phloem. Nutrient status was found to be a possibly predisposing factor for reduced storage quality in celeriac. Balance of boron (B) to calcium (Ca) and zinc (Zn) were studied in two sites. Highest incidence of brown spots and lowest proportion of fresh roots following storage was found in celeriac with the lowest Ca/B ratio in leaves, lowest content of Zn in the leaves and roots and lowest soil pH.
Abstract
No abstract has been registered
Abstract
Brown rot fungi are a marvel and an enigma of Nature. They are capable of depolymerizing holocellulose within wood cell walls without significantly ineralizing lignin. The exact details behind this feat remain unknown, but a staggered mechanism has been identified: 1) an initial step characterized by oxidative degradation of the wood cell wall biopolymers and hypothesized to involve transport of Fe3+ chelated by oxalate into the cell wall, and 2) a second degradation step dominated by hydrolytic enzymes, primarily endoglucanase activity. We subjected spruce wood (Picea abies) to Rhodonia placenta and isolated xylem tissue in the initial stage of degradation. Confocal Raman microscopy revealed oxalate accumulation in the secondary cell wall of a tracheid having fungal hyphae within the lumen. This observation is the first in situ verification of oxalate accumulation within the cell wall during the first step of brown rot degradation.
Authors
Paulina Paluchowska Erik Lysøe Simeon Rossmann Marta Janiszewska Krystyna MICHALAK May Bente Brurberg Jadwiga Śliwka Zhimin YinAbstract
No abstract has been registered
Abstract
The Euura amentorum species group is Holarctic, and in Europe it is most species-rich in the North. Their larvae develop entirely within the female catkins of Salix species: some species bore in the central stalk, whereas others live outside this and feed mainly on the developing seeds. Eight Palaearctic species are treated here as valid, and a key to these is provided. Males of five species are known. Two new species are described from northern Europe: Euura pohjola sp. n. and E. ursaminor sp. n. First records of E. itelmena (Malaise, 1931) from the West Palaearctic are presented. We propose seven new synonymies: Pontopristia montana Lindqvist, 1961 (junior secondary homonym in Euura) with Euura freyja (Liston, Taeger & Blank, 2009); Pontopristia brevilabris Malaise, 1921, Amauronematus fennicus Lindqvist, 1944, Pontopristia boreoalpina Lindqvist, 1961, Pontopristia punctulata Lindqvist, 1961, and Amauronematus pyrenaeus Lacourt, 1995 with Euura microphyes (Förster, 1854); and Pteronidea holmgreni Lindqvist, 1968 with Nematus umbratus Thomson, 1871. Lectotypes are designated for: Amauronematus fennicus Lindqvist, 1944, Nematus amentorum Förster, 1854, Nematus suavis Ruthe, 1859, Pontopristia brevilabris Malaise, 1921, Pontopristia itelmena Malaise, 1931, Pontopristia kamtchatica Malaise, 1931, Pontopristia lapponica Malaise, 1921, Pontopristia latiserra Malaise, 1921, Pontopristia romani Malaise, 1921, and Pristiphora amentorum var. nigripleuris Enslin, 1916. Many new host plant associations are recorded.
Authors
Johannes BreidenbachAbstract
No abstract has been registered
Authors
Gabriela WagnerAbstract
No abstract has been registered