From biology to management of Savi's pine vole (Microtus savii)

Savi's pine vole (Microtus savii) is a rodent species of the Cricetidae family, inhabiting southern European agroecosystems. It is considered to be the main cause of rodent‐attributed damage in Italy. To achieve an effective management, detailed knowledge of this species is needed. However, the available information about this species is fragmentary and incomplete. In this paper, the existing knowledge of Savi's pine vole taxonomy, reproduction, population dynamics, habitat and food preferences is reviewed in order to organise available information and identify priority areas of future research. Some of the changes in farming practices that have occurred in recent decades may have increased the impact of Savi's pine vole populations in crop fields. To manage this pest species effectively, an integrated strategy is recommended (involving habitat management, trapping and, when appropriate, the use of rodenticides). The apparent lack of cyclical population outbreaks and the relatively small litter size and long gestation and interpartum period of this species suggest that it could be more manageable than other vole species, while its strict herbivorous diet, stable population size in open habitats and wide distribution seem to indicate it as an ideal model species for risk assessment studies. © 2015 Society of Chemical Industry     

FraxForFuture—research on European ash dieback in Germany

Journal of Plant Diseases and Protection - European ash dieback caused by the alien, invasive ascomycete species Hymenoscyphus fraxineus currently represents, along with its side effects, the...     

Biochar‐compost substrates in short‐rotation coppice: Effects on soil and trees in a three‐year field experiment

Both biochar and compost may improve carbon sequestration and soil fertility; hence, it has been recommended to use a mixture of both for sustainable land management. Here, we evaluated the effects of biochar–compost substrates on soil properties and plant growth in short rotation coppice plantations (SRC). For this purpose, we planted the tree species poplar, willow, and alder in a no‐till field experiment, each of them amended in triplicate with 0 (= control) or 30 Mg ha^?1 compost or biochar–compost substrates containing 15% vol. (TPS15) and 30% vol. biochar (TPS30). For three years running, we analyzed plant growth as well as soil pH, potential cation exchange capacity (CEC), stocks of soil organic carbon (SOC), total N, and plant‐available phosphate and potassium oxide.Biochar‐compost substrates affected most soil properties only in the topsoil and for a limited period of time. The CEC and total stocks of SOC were consistently elevated relative to the control. After three years the C gain of up to 6.4 Mg SOC ha^?1 in the TPS30 plots was lower than the added C amount. Especially in the case of TPS30 treatment, C input was characterized by the greatest losses after application, although the black carbon of the biochar was not degraded in soil. Additionally, tree growth and woody biomass yield did not respond at all to the treatments. Overall, there were few if any indications that biochar–compost substrates improve the performance of SRC under temperate soil and climate conditions. Therefore, the use of biochar for such systems is not recommended.     

Physionomics and metabolomics-two key approaches in herbicidal mode of action discovery

BACKGROUND: For novel herbicides identified in greenhouse screens, efficient research is important to discover and chemically optimise new leads with new modes of action (MoAs). RESULTS: The metabolic and physiological response pattern to a herbicide can be viewed as the result of changes elicited in the molecular and biochemical process chain. These response patterns are diagnostic of a herbicide's MoA. At the starting point of MoA characterisation, an array of bioassays is used for comprehensive physiological profiling of herbicide effects. This physionomics approach enables discrimination between known, novel or multiple MoAs of a compound and provides a first clue to a new MoA. Metabolic profiling is performed with the use of treated Lemna paucicostata plants. After plant extraction and chromatography and mass spectrometry, changes in levels of approximately 200 identified and 300 unknown analytes are quantified. Check for known MoA assignment is performed by multivariate statistical data analyses. Distinct metabolite changes, which can direct to an affected enzymatic step, are visualised in a biochemical pathway view. Subsequent target identification includes metabolite feeding and molecular, biochemical and microscopic methods. CONCLUSION: The value of this cascade strategy is exemplified by new herbicides with MoAs in plastoquinone, auxin or very‐long‐chain fatty acid synthesis. Copyright © 2011 Society of Chemical Industry     

Land Use and Precipitation Affect Organic and Microbial Carbon Stocks and the Specific Metabolic Quotient in Soils of Eleven Ecosystems of Mt. Kilimanjaro,Tanzania

Tropical ecosystems are under increasing pressure of land‐use changes, strongly affecting the carbon cycle. Conversion from natural to agri‐cultural ecosystems is often accompanied by a decrease in the stocks of organic and microbial carbon (C_org, C_mic) as well as changes in microbial activity and litter decomposition. Eleven ecosystems along an elevation gradient on the slopes of Mt. Kilimanjaro were used to investigate impacts of land‐use changes on C_org and C_mic stocks as well as the specific metabolic respiration quotient (q_sCO₂) in surface soils. Six natural, two semi‐natural and three intensively used agricultural ecosystems were investigated on an elevation gradient from 950 to 3,880 m asl. To estimate the effects of precipitation, rainfall regimes of 3·6 and 20·0 mm were simulated. C_org stocks were controlled by water availability, temperature and net primary production. Agricultural management resulted in decreases of C_org and C_mic stocks by 38% and 76%, respectively. In addition, agricultural systems were characterized by low C_mic:C_org ratios, indicating a decline in available substrate. Enhanced land‐use intensity leads to increased q_sCO₂ (agricultural > semi‐natural > natural). The traditional homegardens stood out as a sustainable land‐use form with high substrate availability and microbial efficiency. Soil CO₂ efflux and q_sCO2 generally increased with precipitation level. We conclude that soils of Mt. Kilimanjaro's ecosystems are highly sensitive to land‐use changes and are vulnerable to changes in precipitation, especially at low elevations. Even though q_sCO₂ was measured under different water contents, it can be used as an indicator of ecosystem disturbances caused by land‐use and management practices. Copyright © 2015 John Wiley & Sons, Ltd.     

Kinetics and electron transport of soil hydrogenases catalyzing the oxidation of atmospheric hydrogen

The soil hydrogenases of chernozem and eolian sand were different with respect to their kinetic properties. Increase of soil moisture above optimum moisture content or prior incubation of the soils under very high H₂-mixing ratios (i.e. 1%) resulted in a decrease of V_max or in an increase of the K_m of the H₂ oxidation reaction. Under anaerobic conditions, the K_m for H₂ was higher and V_max was lower than under aerobic conditions. The anaerobic H₂-oxidation activity of both soils was stimulated by the addition of artificial electron acceptors with redox potentials of at least 80 mV. Ferricyanide as the most efficient stimulator did not function as a final electron acceptor for anaerobic H₂-oxidation, but acted as a catalyst by bypassing a rate-limiting electron transport step. In eolian sand, the aerobic as well as the anaerobic activity for atmospheric H₂ oxidation decreased upon exposure to very high H₂-mixing ratios (i.e. 1%). A similar effect was observed after incubation with ferricyanide which enabled the inflow of excess electrons from soil reductants or added NADH into the electron transport system of the soil hydrogenase with anaerobic activity. The activity for atmospheric H₂ oxidation was regenerated during incubation in H₂-free atmospheres, especially in the presence of oxygen. Inhibition and regeneration were probably due to alterations in components of the soil hydrogenases caused by the extent of a maximal electron flow through the electron transport system of the soil hydrogenases. Two classes of hydrogenase activities were discerned in eolian sand: one predominantly active under aerobic and the other under anaerobic conditions.     

Degradation of Cry1Ab protein from genetically modified maize in the bovine gastrointestinal tract

Immunoblotting assays using commercial antibodies were established to investigate the unexpected persistence of the immunoactive Cry1Ab protein in the bovine gastrointestinal tract (GIT) previously suggested by enzyme-linked immunosorbent assay (ELISA). Samples of two different feeding experiments in cattle were analyzed with both ELISA and immunoblotting methods. Whereas results obtained by ELISA suggested that the concentration of the Cry1Ab protein increased during the GIT passage, the immunoblotting assays revealed a significant degradation of the protein in the bovine GIT. Samples showing a positive signal in the ELISA consisted of fragmented Cry1Ab protein of approximately 17 and 34 kDa size. Two independent sets of gastrointestinal samples revealed the apparent discrepancy between the results obtained by ELISA and immunoblotting, suggesting that the antibody used in the ELISA reacts with fragmented yet immunoactive epitopes of the Cry1Ab protein. It was concluded that Cry1Ab protein is degraded during digestion in cattle. To avoid misinterpretation, samples tested positive for Cry1Ab protein by ELISA should be reassessed by another technique.     

Higher grain yield and higher grain protein deviation underline the potential of hybrid wheat for a sustainable agriculture

Grain yield and protein content are traits of major importance in wheat breeding, but their combination is challenging due to a tight negative correlation. Protein yield and grain protein deviation have been proposed as selection criteria to simultaneously improve both traits. Sedimentation volume is an indicator of protein quality, which plays an important role for bread‐making quality in wheat. All these traits have been investigated in our study with 135 parental inbred lines, their 1,604 hybrids and 10 commercial check varieties evaluated at five environments. The focus of our study was to investigate the usefulness of the grain protein deviation and to define a bivariate model for calculating the grain protein deviation. Further, we compared line and hybrid wheat for grain yield and quality‐related parameters such as protein content and sedimentation volume. The grain protein deviation determined with a bivariate model delivered robust estimates of variance components and enabled a balanced selection of genotypes with improved protein content and grain yield across different quality classes. Although heterosis for protein content and sedimentation volume was negative, hybrids had a higher grain protein deviation as well as higher grain yield at a given sedimentation volume or a given protein content than line varieties.     

Nitrification activity in tropical rain forest soils of the Coastal Lowlands and Atherton Tablelands,Queensland, Australia

Intact soil cores from a montane tropical rain forest site in the Atherton Tablelands (Kauri Creek) and from a lowland tropical rain forest site in the Coastal Lowlands (Bellenden Ker), Queensland, Australia were investigated during different hygric seasons for the magnitude of gross nitrification rates using the Barometric Process Separation technique (BaPS). Pronounced seasonal variations of gross nitrification rates were found at both sites with highest values during the transition period between dry and wet season (montane site: 24.0 mg N (kg SDW)^—1 d^—1; lowland site: 13.1 mg N (kg SDW)^—1 d^—1) and significantly lower rates of gross nitrification during the dry and wet season. Rates of gross nitrification were always higher at the montane site than at the lowland site, but the opposite was found for N₂O emissions. The results indicated that the high losses of N₂O at the lowland tropical rain forest site may be contributed largely by high denitrification activity due to its wetter and warmer climate as compared to the dryer and colder climate at the montane tropical rain forest site. This conclusion was supported by analysis of cell numbers of microbes involved in N‐cycling. Higher numbers of denitrifiers were present at the lowland site, whereas higher numbers of nitrifiers were found at the montane site.