Chemical Diversity as a Function of Temperature in Six Northern Diatom Species

In this study, we investigate how metabolic fingerprints are related to temperature. Six common northern temperate diatoms (Attheya longicornis, Chaetoceros socialis, Chaetoceros furcellatus, Porosira glacialis, Skeletonema marinoi, and Thalassiosira gravida) were cultivated at two different temperatures, 0.5 and 8.5 °C. To exclude metabolic variations due to differences in growth rates, the growth rates were kept similar by performing the experiments under light limited conditions but in exponential growth phase. Growth rates and maximum quantum yield of photosynthesis were measured and interpreted as physiological variables, and metabolic fingerprints were acquired by high-resolution mass spectrometry. The chemical diversity varied substantially between the two temperatures for the tested species, ranging from 31% similarity for C. furcellatus and P. glacialis to 81% similarity for A. longicornis. The chemical diversity was generally highest at the lowest temperature.     

Reduced breeding success in white-tailed eagles at Smøla windfarm,western Norway,is caused by mortality and displacement

Climate change scenarios and efforts to reduce CO₂ emissions have increased the focus on wind power and other renewable energy sources. Despite producing “clean” electricity, windfarms do have impacts on the environment. We studied the impact from a coastal windfarm on the breeding success of white-tailed eagles (Haliaeetus albicilla) at Smøla, western Norway by means of a BACI (before–after–control–impact) approach. The objective was to compare pre- and post-construction breeding success. A 10 year dataset from 47 eagle territories were analyzed using a generalized linear mixed model. Successful breeding was used as a response variable, while distance to turbines, distance to roads and before/after turbine construction were used as predictors. There was a significant effect of the interaction between time period and distance to turbines, showing that territories within 500 m from the turbines in the post-construction period experienced significantly lower breeding success than the same territories before construction. We found that this effect was most likely due to territories being vacated. The results emphasize the importance of using a BACI approach when assessing possible effects from wind-power production on breeding birds, especially for species breeding at low densities. It also emphasizes the importance of conducting thorough pre-construction studies on vulnerable bird species.     

Characterization and Cytotoxicity Studies of the Rare 21:4 n-7 Acid and Other Polyunsaturated Fatty Acids from the Marine Opisthobranch Scaphander lignarius,Isolated Using Bioassay Guided Fractionation

The marine opisthobranch Scaphander lignarius has been analyzed in the systematic search for novel bioactive compounds in Arctic marine organisms using bioassay guided fractionation. A number of highly cytotoxic fractions were shown to contain mainly polyunsaturated fatty acids (PUFAs). Selected PUFAs were isolated and identified using both liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR). It was shown that the opisthobranch contained unusual PUFAs such as several ω3 fatty acids and the ω7 heneicosa-5,8,11,14-tetraenoic acid (21:4 n-7) not isolated before. The organism was shown to be a very rich source of PUFAs and the activity of the isolated compounds against a range of human cancer cell lines (melanoma, colon carcinoma and breast carcinoma) is further reported. The ω7 PUFA was significantly more cytotoxic in comparison with reference ω6 arachidonic and ω3 eicosapentaenoic acid. A noteworthy non-selective cytotoxicity against normal lung fibroblasts was also established. The paper contains isolation protocols in addition to cytotoxicity data of the isolated compounds. The potential of marine mollusks as a source for rare PUFAs is also discussed.     

Cervid herpesvirus 2 infection in reindeer: A review

Herpesviruses of the genus Varicellovirus are known to infect and cause disease in a variety of ruminant species, but the impact of cervid herpesvirus 2 (CvHV2) in reindeer (Rangifer tarandus) is mostly unknown. Reindeer is a circum-polar species with a total estimated number of more than 5 million animals. Mortality may reach high values, as in northern Norway, especially in calves (37%; 2005–2006), and disease can potentially account for some of this mortality. CvHV2 has been isolated during a natural outbreak of infectious keratoconjunctivitis, indicating an etiologal link. Serological screening has shown that CvHV2 infection is prevalent in Northern Norway and experimental infection studies have demonstrated that viremia, latency and vertical transmission occur for CvHV2. The present review aims at summarizing current knowledge on the epidemiology, pathogenesis and molecular virology of CvHV2.     

Changes in the potato (Solanum tuberosum L.) tuber at the onset of dormancy and during storage at 23°C and 3°C. II. Evaluation of protein patterns

Summary The changes in polypeptide profiles (2D-PAGE) occurring in the soluble and microsomal fractions of parenchymatic tissue of potato (Solanum tuberosum L.) tubers were studied during the last 30 d of maturation and during storage at 23°C and 3°C. The major changes were observed in the last period of tuber maturation, when several polypeptides disappeared and new ones appeared. At both 23°C and 3°C specific polypeptides disappeared in dormant tubers and new polypeptides appeared during storage. At 3°C specific changes in protein composition occurred, particularly in the microsomal fraction. The changes in polypeptide profiles are discussed in relation to the transition from “sink” to “source” of the tuber, the onset of dormancy and of sprouting ability and the activation of cold acclimation responses. The results are also discussed on the basis of the physiological and biochemical changes that occur in the parenchymatic tissue.     

Changes in the potato (Solanum tuberosum L.) tuber at the onset of dormancy and during storage at 23°C and 3°C. I. Biochemical and physiological parameters

Summary In the last 30 d of potato (Solanum tuberosum L.) tuber growth metabolic activity decreased. Levels of glucose-6-P and sucrose in whole tuber tissues declined and in tuber slices there was a decrease in the uptake from the medium and in the incorporation into macromolecules of [U-¹⁴C]sucrose. During storage at 23°C only the uptake of [U-¹⁴C]sucrose increased concomitant with tuber sprouting, indicating a possible involvement of the transport mechanisms in dormancy breaking. At 3°C, levels of reducing sugars and sucrose increased in response to the low temperature and increased release of K⁺ and malondialdehyde levels indicated cell membrane damage. The cell membrane functionality was restored at sprouting. The sprouting potential of the tubers was evaluated using the sprouting ability of single-bud explants (“seedcores”) in response to water, GA₃ or ABA dips. This sprouting potential of tubers changed with stage of tuber growth and storage duration and temperature, indicating that the tissue hormonal state changed strongly throughout tuber life, probably in relation with the “sink” to “source” transition.     

Evaluation of strategies to optimize training populations for genomic prediction in oat (Avena sativa)

Genomic selection is a promising breeding methodology that could increase selection accuracy and intensity and reduce generation interval. As the cost of genotyping decreases, it will be important to optimize training populations for costly phenotypic experiments for many complex traits. The aim of this research was to evaluate different optimization strategies, by using historical data from the Norwegian oat breeding programme at Graminor. In this paper, we focus on the optimization criteria: genetic diversity, phenotypic variance and genetic similarity between the training and testing populations. The four training population strategies—prediction core, diversity core, phenotypic selection and random selection—were applied to an oat candidate population of 1124 lines. An independent testing population was used to calculate the mean prediction abilities for the traits days to heading and plant height. Moreover, the strategies were tested in three independent wheat populations. The results showed that prediction core was the most promising strategy to select training populations with high genetic similarity to the testing set, high genetic diversity, and high phenotypic variance, which resulted in higher prediction ability across population sizes and traits.     

Increased mortality of fish due to changing Al-chemistry of mixing zones between limed streams and acidic tributaries

The present study is mainly focusing on mortality variations of fish due to changing Alchemistry of mixing zones. An artificial mixing zone was made by pumping water from a limed stream and an acidic tributary into a mixing channel. Atlantic salmon (Salmo salar L.) parr were exposed to the mixed water, limed stream water, and acidic tributary water. Mortality, blood haematocrit and plasma Cl^?-concentration were recorded. Neither mortality, nor changes in haematocrit and plasma Cl^? were observed when fish were exposed to limed water, while in both acidic and mixed water, mortalities and loss of plasma Cl^? were observed. The highest mortality rates were found within the initial part (0 to 20 s) of the mixing zone. Blood haematocrit increased only in fish exposed to acidic tributary water. Our results shows that changes in Al-chemistry and subsequent Al-polymerization occur when acidic tributary water is mixed with limed stream water. We have also demonstrated that the toxicity which can arise in mixing zones are greater than in the original acidic water before mixing. The variations in mortality observed are associated with the quality and quantity of Al-polymerization as well as ageing of the polymers.     

Population Density of Brown Trout (Salmo trutta) in Extremely Dilute Water Qualities in Mountain Lakes in Southwestern Norway

We have examined populations of brown trout in low-conductivity mountain lakes (5.0?C13.7 ??S/cm and 0.14?C0.41 mg/l Ca) in southwestern Norway during the period 2000?C2010. Inlets to the lakes were occasionally even more dilute (2007; conductivity?=?2.9?C4.8 ??S/cm and Ca?=?0.06?C0.17 mg/l). The combination of pH and conductivity was the best predictor to fish status (CPUE), indicating that availability of essential ions was the primary restricting factor to fish populations in these extremely diluted water qualities. We suggest that conductivity <5 ??S/cm is detrimental to early life stages of brown trout, and subsequently that there are lakes in these mountains having too low conductivity to support self-reproducing trout populations. Limited significance of alkalinity, Ca, Al, and color suggests that effects of ion deficit apparently overruled the effects of other parameters.     

Assessment of seafood processing wastes as alternative sources of Selenium in plant production

Abstract

In some parts of the world, the soil selenium (Se) content is too low to ensure the Se level recommended for human or animal consumption in the crops produced. In order to secure a desired concentration of Se in crops, Se has been applied as mineral fertilizer to agricultural fields. Since only a minor part of the inorganic Se applied is utilized by plants and small increases in Se concentrations in, e.g., drinking water, may be toxic, the method is somewhat controversial. As an alternative to Se-enriched mineral fertilizer, different seafood-processing wastes have been examined as a source for Se in crop production. Both in greenhouse pot experiments and field trials the Se in seafood waste was not plant-available during the first growing season. There was no significant difference between the Se concentration in wheat growing in soil without added Se and in soil receiving Se from seafood waste in amounts ranging from 0.9 to 9 g ha^?1. Neither was any residual effect of Se in seafood waste seen during a second year growth period. Thus, seafood-processing waste cannot be regarded as a potential source of Se in crop production. Possible mobilization of formerly applied Se, as seafood-processing waste or Se enriched mineral fertilizer due to changes in soil redox conditions were examined in a leaching experiment. The mobility of formerly applied Se was generally very low, but the results indicated that under permanently wet soil conditions leaching of Se may occur in plant dormant periods in soils with low organic matter content and high pH.