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1.
Wheat stem rust, caused by the fungus Puccinia graminis f. sp. tritici (Pgt), is a notoriously damaging disease of wheat and barley. Pgt requires two hosts to complete its lifecycle; undergoing asexual reproduction on cereal crops and completing sexual reproduction on Berberis spp. The latter stage of its lifecycle is of particular importance in temperate regions such as western Europe, where asexual urediniospores are unable to survive cold winter weather. In the past, the crucial role of Berberis in the lifecycle of stem rust led to intensive eradication campaigns, initially carried out by farmers in the face of hostile scientific opinion. In the United Kingdom, common barberry (Berberis vulgaris) is today a relatively rare plant. Stem rust is, however, currently experiencing a resurgence; at the same time, there has been a general increase in the prevalence of barberry and an upsurge in its planting which, in the United Kingdom, is associated with attempts to encourage the endangered barberry carpet moth (Pareulype berberata). This article situates current developments within a broader chronological framework, examining changing attitudes towards barberry and rust in England in the past and the history of the plant's use and cultivation. It assesses how widespread B. vulgaris really was in the environment historically, and thus the scale of its eradication. We suggest that Berberis was never widely established as an archaeophyte in the United Kingdom. Current attempts to re-establish it are based on a misunderstanding of the plant's historical status and could potentially pose a serious threat to food security. 相似文献
2.
T. Schöneberg K. Kibler F. E. Wettstein T. D. Bucheli H. R. Forrer T. Musa F. Mascher M. Bertossa B. Keller S. Vogelgsang 《Plant pathology》2019,68(1):173-184
High occurrence of Fusarium poae (FP) and Fusarium langsethiae (FL) and their mycotoxins nivalenol (NIV) and T-2/HT-2 have been observed in Swiss oats. Early prediction of mycotoxin levels is important for farmers and the cereal industry to minimize the risk of contaminated food and feed. Therefore, climate chamber experiments were conducted to investigate the influence of different temperatures (10, 15, 20 °C) and durations (4, 8, 12 h) at 99% relative humidity (RH) on the infection of oats with FP and FL. In addition, to discover the most susceptible period of oats, artificial FL inoculations were conducted at different growth stages. Field experiments were performed to observe the dispersal of these fungal species within the field and to investigate the weather conditions that influence the dispersal. The climate chamber experiments revealed higher contamination with NIV and T-2/HT-2 in the 10 °C treatments and with a prolonged humidity duration of 12 h 99% RH. Inoculations of oat plants at early (DC 61) and mid (DC 65) anthesis, led to higher FL infection and T-2/HT-2 accumulation in the grains compared with treatments at earlier growth stages, which might be due to an increased susceptibility during anthesis. No indication for spore dispersal was observed in the field experiments. The results obtained, together with the cropping factors that influence infection and mycotoxin production, could be used as a first step in developing forecasting models to predict the contamination of oats with the mycotoxins NIV and T-2/HT-2. 相似文献
3.
Ren Reiser Viktor Stadelmann Peter Weisskopf Lina Grahm Thomas Keller 《植物养料与土壤学杂志》2020,183(3):316-326
Oxygen diffusion rate (ODR) and redox potential (EH) are quantitative indices representing oxygen availability and redox status in soils, which is valuable information for better understanding causes and effects of soil aeration. Because these indices are spatially and temporally highly variable, continuous measurements and adequate numbers of repetitions are essential for accurate in situ monitoring. Here, we present a new, fully automated recording system for in situ measurements where ODR and EH are measured at the same platinum electrode. The conflict between electrode polarization for ODR and the resulting biased EH readings is solved by reducing the polarization time and introducing a recovery interval between two consecutive measurement cycles. The shorter polarization time ensures accurate EH readings. It also results in moderately overestimated ODR readings, but this can be corrected before data analysis. The recovery interval restricts temporal resolution of the EH‐ODR data pairs to 8 h. We illustrate the use of the system with measurements in a field experiment in Zürich, Switzerland. ODR curves at different depths ran roughly parallel to the corresponding curves of O2 concentration in soil air but ODR was much more sensitive to precipitation. Low ODR was a necessary but not a sufficient condition for declining EH. EH ran parallel to O2 concentration in soil air rather than to ODR. The fully automated system allows for time series of replicate measurements in multifactorial field studies with reasonable labor requirements. It may be particularly suitable for studies examining the effects of soil tillage, compaction, and irrigation, where structure‐related soil properties such as porosity, gas permeability, and soil aeration play a dominant role. 相似文献
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Tadahisa MASHITA Hiroaki KAMISHINA Yuya NAKAMOTO Yosuke AKAGI Ataru NAKANISHI Yusuke HARASAKI Tsuyoshi OZAWA Takashi UEMURA Yui KOBATAKE Shunsuke SHIMAMURA Naoki KITAMURA Sadatoshi MAEDA Yuji UZUKA Gerry SHAW Jun YASUDA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(4):433-438
The aim of this study was to evaluate the prognostic value of concurrent measurement of
serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary
T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent
measurement of these would provide a more accurate prediction of functional outcome in
dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control
clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The
association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2),
deep pain perception and surgical outcome were evaluated with logistic regression analysis
after three months for all 94 surgically treated dogs. Sensitivity to predict
non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both.
Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were
significantly correlated with surgical outcome (P<0.05); however, deep
pain perception was not (P=0.41). The results of logistic regression
analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for
serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity
and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6
ng/ml, using T2H/L2 value of>0.84 and using both
serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%,
respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful
for predicting long-term outcome in dogs with thoracolumbar IVDH. 相似文献
6.
Comparison of the effects of propofol or alfaxalone for anaesthesia induction and maintenance on respiration in cats 下载免费PDF全文
Ivo Campagna Andrea Schwarz Stefanie Keller Regula Bettschart‐Wolfensberger Martina Mosing 《Veterinary anaesthesia and analgesia》2015,42(5):484-492
ObjectiveTo compare the effects of propofol and alfaxalone on respiration in cats.Study designRandomized, ‘blinded’, prospective clinical trial.AnimalsTwenty cats undergoing ovariohysterectomy.MethodsAfter premedication with medetomidine 0.01 mg kg−1 intramuscularly and meloxicam 0.3 mg kg−1 subcutaneously, the cats were assigned randomly into two groups: group A (n = 10) were administered alfaxalone 5 mg kg−1 minute−1 followed by 10 mg kg−1 hour−1 intravenously (IV) and group P (n = 10) were administered propofol 6 mg kg−1 minute−1 followed by 12 mg kg−1hour−1 IV for induction and maintenance of anaesthesia, respectively. After endotracheal intubation, the tube was connected to a non-rebreathing system delivering 100% oxygen. The anaesthetic maintenance drug rate was adjusted (± 0.5 mg kg−1 hour−1) every 5 minutes according to a scoring sheet based on physiologic variables and clinical signs. If apnoea > 30 seconds, end-tidal carbon dioxide (Pe′CO2) > 7.3 kPa (55 mmHg) or arterial haemoglobin oxygen saturation (SpO2) < 90% occurred, manual ventilation was provided. Methadone was administered postoperatively. Data were analyzed using independent-samples t-tests, Fisher's exact test, linear mixed-effects models and binomial test.ResultsManual ventilation was required in two and eight of the cats in group A and P, respectively (p = 0.02). Two cats in both groups showed apnoea. Pe′CO2 > 7.3 kPa was recorded in zero versus four and SpO2 < 90% in zero versus six cats in groups A and P respectively. Induction and maintenance dose rates (mean ± SD) were 11.6 ± 0.3 mg kg−1 and 10.7 ± 0.8 mg kg−1 hour−1 for alfaxalone and 11.7 ± 2.7 mg kg−1 and 12.4 ± 0.5 mg kg−1 hour−1 for propofol.Conclusion and clinical relevanceAlfaxalone had less adverse influence on respiration than propofol in cats premedicated with medetomidine. Alfaxalone might be better than propofol for induction and maintenance of anaesthesia when artificial ventilation cannot be provided. 相似文献
7.
The detection of hidden F-injury of forest trees by a simple colorimetric determination of peroxidase actívity . The paper describes a simple routine method for determining colorimetrically peroxidase activity (p. a.) in foliage of forest tree species, including conifers. The effect of factors such as foliage age, F Content, external F dust, necrosis etc. on p. a. is investigated. Analyses of plants exposed at different distances to F exhalates of an aluminum plant show that with decreasing distance F content and p. a. increase. P. a. thus is an indicator of air pollution effects on tree physiology even in the range where no visible symptoms of injury occur. 相似文献
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9.
Gerry Van Leeuwen Senior Consultant 《国际木业》2003,33(11):3
尽管在过去10年里日本集成材的进口取得惊人增长,然而值得注意的是日本本国的结构集成材的生产甚至增长更快. 相似文献
10.