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51.
Charlotte Martin Torsten Schöneberg Susanne Vogelgsang Romina Morisoli Mario Bertossa Brigitte Mauch-Mani Fabio Mascher 《European journal of plant pathology / European Foundation for Plant Pathology》2018,152(3):621-634
Fusarium head blight (FHB) caused by Fusarium graminearum (FG) is a destructive disease impacting barley worldwide. The disease reduces the grain yield and contaminates grains with mycotoxins, such as the trichothecene deoxynivalenol (DON). Although the infection mainly affects the grain yield, little is known about its impact on grain structural and biochemical properties. Yet, such information is instrumental to characterize the facets of resistance in the grains. After artificial inoculation of six barley cultivars with FG in a 2 years field test, different levels of symptoms on spikes, of colonisation of grains and of DON content were observed. The infections caused a reduction in grain weight and an average decrease of 10% of the β-glucan content in grains, indicating alterations of grain filling, composition and structure. According to our results, we postulate the presence of two distinct resistance mechanisms in the grain, tolerance to grain filling despite infection as well as the inhibition of mycotoxin accumulation. Differently to wheat, in barley, type IV resistance (tolerance of the grain to infection) is directly linked with type III resistance (resistance against kernel infection). The resistance against toxin accumulation (named type V resistance in wheat) appeared to be independent to all other resistance types. Generally, the resistance was significantly influenced by the environment and by genotype x environment interactions explaining the generally weak stability of resistance in barley. Interestingly, a significant and inverse relationship between DON contamination and β-glucan content in grains suggests that high β-glucan content in grains contributes to type V resistance. 相似文献
52.
Six phosphorus (P) fertilizers recycled from sewage sludge [Struvite SSL, Struvite AirPrex®, P‐RoC®, Mephrec®, Pyrolysis coal and Ash (Mg‐SSA)] were tested for their plant availability in potted soil of pH 7.2 under greenhouse conditions. The crop sequence simulated a rotation of red clover (Trifolium pratense L.), maize (Zea maize L.), and ryegrass (Lolium perenne L.). Other P fertilizer treatments included: Phosphate Rock (PR), Calcium dihydrogen phosphate [Ca(H2PO4)2], and an unfertilized control. Additionally, soil was regularly inoculated with two strains of plant growth‐promoting rhizobacteria (PGPR; Pseudomonas sp. Proradix, and Bacillus amyloliquefaciens) to test their ability to increase P availability to plants. Sequential P fractionation was conducted to link the amount of readily available P in fertilizers to plant P acquisition. Shoot P content and dry matter of maize decreased in the following order: Struvite SSL ≥ Ca(H2PO4)2 > P‐RoC® ≥ Struvite AirPrex® ≥ Mephrec® > Pyrolysis coal ≥ Mg‐SSA ≥ PR ≥ unfertilized. Rhizobacteria did not affect shoot biomass or P content. The results show that red clover might have mobilized substantial amounts of P. Sequential P fractionation was not suitable to predict the efficacy of the fertilizers. Generally, the sewage sludge‐based fertilizers tested proved to be suitable alternative P sources relevant to organic farming systems. However, the efficacy of recycled fertilizers is strongly dependent on their specific production conditions. 相似文献
53.
Xiaolu Tang Lutz Fehrmann Fengying Guan David I. Forrester Rubén Guisasola César Pérez-Cruzado Torsten Vor Yuanchang Lu Juan Gabriel Álvarez-González Christoph Kleinn 《Annals of Forest Science》2017,74(1):12
Key message
A generalized algebraic difference approach (GADA) developed in this study improved the estimation of aboveground biomass dynamics of Cunninghamia lanceolata (Lamb.) Hook and Castanopsis sclerophylla (Lindl.) Schott forests. This could significantly improve the fieldwork efficiency for dynamic biomass estimation without repeated measurements.Context
The estimation of biomass growth dynamics and stocks is a fundamental requirement for evaluating both the capability and potential of forest carbon sequestration. However, the biomass dynamics of Cunninghamia lanceolata and Castanopsis sclerophylla using the generalized algebraic difference approach (GADA) model has not been made to date.Aims
This study aimed to quantify aboveground biomass (AGB, including stem, branch and leaf biomass) dynamics and AGB increment in C. lanceolata and C. sclerophylla forests by combining a GADA for diameter prediction with allometric biomass models.Methods
A total of 12 plots for a C. lanceolata plantation and 11 plots for a C. sclerophylla forest were selected randomly from a 100 m × 100 m systematic grid placed over the study area. GADA model was developed based on tree ring data for each stand.Results
GADA models performed well for diameter prediction and successfully predicted AGB dynamics for both stands. The mean AGB of the C. lanceolata stand ranged from 69.4 ± 7.7 Mg ha?1 in 2010 to 102.5 ± 11.4 Mg ha?1 in 2013, compared to 136.9 ± 7.0 Mg ha?1 in 2010 to 154.8 ± 8.0 Mg ha?1 in 2013 for C. sclerophylla. The stem was the main component of AGB stocks and production. Significantly higher production efficiency (stem production/leaf area index) and AGB increment was observed for C. lancolata compared to C. sclerophylla.Conclusion
Dynamic GADA models could overcome the limitations posed by within-stand competition and limited biometric data, can be applied to study AGB dynamics and AGB increment, and contribute to improving our understanding of net primary production and carbon sequestration dynamics in forest ecosystems.54.
Phosphoinositides are involved in a large number of processes in cells and it is very demanding to study individual protein-lipid interactions in vivo due to their rapid turnover and involvement in simultaneous events. Supported lipid bilayers (SLBs) containing controlled amounts of phosphoinositides provide a defined model system where important specific recognition events involving phosphoinositides can be systematically investigated using surface sensitive analytical techniques. The authors have demonstrated the formation and characterized the assembly kinetics of SLBs incorporating phosphatidylinositol 4,5-biphosphate (PIP(2); 1, 5, and 10 wt?%) and phosphoinositol-3,4,5-triphosphate (1 wt?%) using the quartz crystal microbalance with dissipation monitoring and fluorescence recovery after photobleaching. An increased fraction of phosphoinositides led to a higher barrier to liposome fusion, but full fluidity for the phosphatidylcholine lipids in the formed SLB. Significantly, the majority of phosphoinositides were shown to be immobile. X-ray photoelectron spectroscopy was used for the first time to verify that the PIP(2) fraction of lipids in the SLB scales linearly with the amount mixed in from stock solutions. 相似文献
55.
Browsing by free-living ungulates is a serious threat to forest regeneration. Although predictors of browsing and potential consequences are well researched, less information is available in the scientific literature about possible solutions to the problem. We investigated whether a large-scale game management system in a traditional sport hunting culture has the potential to effectively reduce browsing damage. Our analysis was based on browsing survey data from 2006 and 2009 covering more than 25,000 km2 in Bavaria, Germany. After an initial assessment of browsing damage throughout Bavaria in 2006, game management plans were altered, and the effect of this intervention was assessed in 2009. Browsing damage clearly declined in 2009 in areas where the suggested deer harvests were increased in 2006 game management plans. This is the first report of a successful implementation of a large-scale game management system aiming at reducing browsing damage to facilitate unfenced forest regeneration. 相似文献
56.
57.
Thermal utilization of sewage sludge through mono‐incineration or gasification results in phosphorus (P) rich sewage sludge ash (SSA) that must be returned to agricultural production systems to fulfill the need for recycling of P resources contained in wastewater streams. As the plant‐availability of P contained in SSA is low, we propose feeding SSA directly into the production of superphosphate fertilizers, thereby opening a further pathway for the recycling of phosphorus (P) from wastewater streams to agricultural production systems by using available technologies. We carried out laboratory‐scale production of superphosphate test‐products, in which rock phosphate (RP) was partially replaced with SSA (gasification) before digestion with concentrated sulfuric acid, and evaluated these products with regard to the solubility of P in H2O and neutral ammoniumcitrate solution. We further carried out a growth‐chamber experiment (28 d) using maize (Zea mays L. cv. Sulano) as a model plant on a low P (0.4 mg PCAL 100g?1), high pH (7.6) substrate to evaluate plant P availability of the test products. Our laboratory‐scale results show that at least 8% of P from RP can be replaced by P from SSA while maintaining both the high solubility of P in the fertilizer product and the growth of maize compared to pure RP digested with concentrated sulfuric acid. Further substitution of RP through SSA decreased the total P concentration of the test products, as well as the relative amounts of P soluble in H2O and neutral ammoniumcitrate solution, which affected early plant development of maize. 相似文献
58.
Oevermann A Botteron C Seuberlich T Nicolier A Friess M Doherr MG Heim D Hilbe M Zimmer K Zurbriggen A Vandevelde M 《Veterinary microbiology》2008,130(3-4):320-329
This paper describes the prevalence of brain lesions in the Swiss fallen stock population of small ruminants. 3075 whole brains (75% sheep, 25% goats) were collected as part of a year-long active survey of transmissible spongiform encephalopathies (TSEs) in small ruminants conducted by the Swiss authorities between July 2004 and July 2005. All fallen stock brains were systematically examined by histopathology to obtain reliable data on histologically identifiable brain lesions. Lesions were found in an unexpectedly high number of animals (8.1% of all examined brains). A wide spectrum of diseases was detected showing that this approach provides an excellent opportunity to screen for the prevalence of neurological diseases. Encephalitic listeriosis was by far the most frequent cause of CNS lesions in both species and its prevalence was unexpectedly high when compared to notified confirmed cases. In conclusion, the prevalence of listeriosis as estimated by passive surveillance based on the notification of clinical suspects has been underestimated in the past. 相似文献
59.
Anna Lena Kunz Antje Labes Jutta Wiese Torsten Bruhn Gerhard Bringmann Johannes F. Imhoff 《Marine drugs》2014,12(4):1699-1714
Eight streptophenazines (A–H) have been identified so far as products of Streptomyces strain HB202, which was isolated from the sponge Halichondria panicea from the Baltic Sea. The variation of bioactivities based on small structural changes initiated further studies on new derivatives. Three new streptophenazines (I–K) were identified after fermentation in the present study. In addition, revised molecular structures of streptophenazines C, D, F and H are proposed. Streptophenazines G and K exhibited moderate antibacterial activity against the facultative pathogenic bacterium Staphylococcus epidermidis and against Bacillus subtilis. All tested compounds (streptophenazines G, I–K) also showed moderate activities against PDE 4B. 相似文献
60.
OBJECTIVE: To compare results obtained by use of laparoscopyassisted abomasopexy versus omentopexy via right flank laparotomy for the treatment of dairy cows with left displaced abomasum (LDA). ANIMALS: 120 dairy cows with an LDA. PROCEDURE: In a prospective clinical trial, cows were randomly allocated to the abomasopexy group (laparoscopy-assisted abomasopexy) or to the control group (omentopexy via right flank). Data were obtained during the first 5 days after surgery and 6 weeks and 6 months after surgery. RESULTS: 59 of 60 cows in the abomasopexy group and all 60 cows in the control group were treated successfully. Median duration was shorter for the laparoscopic procedure (27.5 minutes), compared with that for the control group (38 minutes). Five cows in the abomasopexy group had wound complications and 2 had LDA relapses, compared with 2 wound complications and no relapses in the control group. During the 5 days after surgery, the abomasopexy group had a significantly higher increase in rate of energy intake and milk yield and a more rapid return to reference range for serum glutamic dehydrogenase activity and total bilirubin concentration, compared with results for the control group. CONCLUSIONS AND CLINICAL RELEVANCE: Success rates were almost equal for both methods. Advantages of the laparoscopic abomasopexy procedure include practicality, low risk of complications, and rapid postoperative recovery. Contraindications are cardiopulmonary diseases. Other disadvantages include the cost of the instruments and inability to perform the procedure in cows with abomasal adhesions. 相似文献