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951.
The economically most damaging disease to winter rye is brown rust (Puccinia recondita f.sp.secalis Rob.ex Desm.). There are fungicides of different drug groups in order to fight brown rust in agriculture. Usually mixtures of different active ingredients with different modes of action can be used for the treatment of fungal pathogens. In experiments single agents like pyrazole-carboxamides, azoles and strobilurines were compared to drug combination products like azole strobilurin, azole-carboxamide, or azole carboxamide-strobilurin mixture and their fungicide performance was determined. The active ingredients Epoxiconazole, Pyraclostrobin, and Fluxapyroxad were tested. In eight trials from 2012 to 2013 Fluxapyroxad reached the highest levels of efficiency for P. recondita. Pyraclostrobin or the combination of Pyraclostrobin and Epoxiconazole showed higher efficiencies than Epoxiconazole or the combination of Epoxiconazole and Metconazole in all trials. The thousand seed weight and income from the harvest reflect the efficiency against P. recondita. Both azole strobilurin mixtures as well as the azole carboxamide mixtures are suitable for the control of leaf rust in agriculture. In order to minimize the risk of resistance to strobilurin and azole carboxamide mixtures should be used alternately. 相似文献
952.
R. Kröger M. T. Moore C. M. Cooper M. M. Holland 《Water, air, and soil pollution》2009,201(1-4):209-218
Flooded post-harvest rice paddies were examined as systems for reducing diazinon (organophosphate insecticide) concentrations in stormwater runoff. Two paddies were cultivated in Oryza sativa L. and amended with a 3-h simulated stormwater diazinon runoff event. Initial diazinon adsorption peaked at 347 and 571 μg kg?1 (3% mass load reduction) for mean above-ground plant tissue concentrations in each pond, respectively. Subsequent senescence of above-ground tissue showed significant decreases in tissue mass (r 2?=?0.985) and adsorbed diazinon mass (90?±?4% and 82?±?1%) within 1 month of amendment. There were no corollary increases in water column diazinon concentrations. Furthermore, control O. sativa tissue placed within the treatment ponds had below-detectable levels of diazinon throughout the decomposition phase, suggesting a lack of within pond transference of dissipated diazinon. This study shows the relative effectiveness of diazinon adsorption by post-harvest rice plants and a potential mitigation strategy of senescence and pesticide degradation for contaminated tailwater. 相似文献
953.
Soil organic matter (SOM) represents one of the largest reservoirs of carbon on the global scale. Thus, the temperature sensitivity
of bulk SOM and of different SOM fractions is a key factor determining the response of the terrestrial carbon balance to climatic
warming. We condense the available knowledge about the potential temperature sensitivity and the actual temperature sensitivity
of decomposition in situ, which ultimately depends on substrate availability. We review and evaluate contradictory results
of estimates of the temperature sensitivity of bulk SOM and of different SOM fractions. The contradictory results demonstrate
a need to focus research on biological and physicochemical controls of SOM stabilisation and destabilisation processes as
a basis for understanding strictly causal relationships and kinetic properties of key processes that determine pool sizes
and turnover rates of functional SOM pools. The current understanding is that temperature sensitivity of SOM mineralisation
is governed by the following factors: (1) the stability of SOM, (2) the substrate availability, which is determined by the
balance between input of organic matter, stabilisation and mineralisation of SOM, (3) the physiology of the soil microflora,
its efficiency in substrate utilisation and its temperature optima and (4) physicochemical controls of destabilisation and
stabilisation processes, like pH and limitation of water, oxygen and nutrient supply. As soil microflora is functionally omnipotent
and most SOM is of high age and stability, the temperature dependence of stable SOM pools is the central question that determines
C stocks and stock changes under global warming. 相似文献
954.
955.
956.
L. Roepstorff A. Egenvall M. Rhodin A. Byström C. Johnston P. R. van Weeren M. Weishaupt 《Equine veterinary journal》2009,41(3):292-296
Reasons for performing study: At rising trot the rider sits alternately down on one diagonal pair of limbs and rises up on the other. The possible effects on asymmetry of locomotion induced by rising trot have rarely been studied. Objectives: To demonstrate whether, and if so to what extent, rising trot causes asymmetrical loading in the vertical ground reaction force (VGRF) and/or asymmetrical effects on the locomotion pattern, comparing left and right side. Methods: Seven elite horses were ridden in left and right rising trot on a treadmill, while VGRF and kinematics were measured, with the horses' neck raised, the poll high and the bridge of the nose slightly in front of the vertical. Results: Force loading was generally increased in the limbs of the sitting diagonal. The lumbar back was lower between mid‐stances of the sitting and nonsitting stance, pelvic roll was limited and the tuber coxae heights were lower on the sitting side. Maximal hindlimb protraction was decreased. Forelimb retraction was increased and the T6 height decreased. Conclusion: The rider movement induces an uneven biphasic load that affects the back, pelvis and limb kinematics and VGRF. Potential relevance: The generally advocated technique of alternating limbs when riding in rising trot is supported. The VGRF changes between rising on the left or right diagonal were distinct, but minor in absolute terms and therefore unlikely to have direct impact on the occurrence of locomotor injuries. Knowledge of an increase of asymmetry in rising trot is potentially useful for riders/trainers. 相似文献
957.
C. B. Gómez Álvarez M. Rhodin A. Byström W. Back P. R. van Weeren 《Equine veterinary journal》2009,41(3):297-300
Reasons for performing study: Treadmill locomotion is frequently used for training of sport horses, for diagnostic purposes and for research. Identification of the possible biomechanical differences and similarities between the back movement during treadmill (T) and over ground (O) locomotion is essential for the correct interpretation of research results. Objectives: To compare the kinematics of the thoracolumbar vertebral column in treadmill and over ground locomotion in healthy horses. Methods: Six sound Dutch Warmblood horses trotted on a T and O during 10 s at their own preferred velocity (mean ± s.d. 3.6 ± 0.3 m/s T and 3.6 ± 0.1 m/s O), which was the same in both conditions. Kinematics of the vertebral column was captured by infrared cameras using reflective skin markers attached over the spinous processes of selected vertebrae and other locations. Flexion‐extension and lateral bending range of motion (ROM), angular motion pattern (AMP) and intravertebral pattern symmetry (IVPS) of 5 vertebral angles (T6‐T10‐T13, T10‐T13‐T17, T13‐T17‐L1, T17‐L1‐L3 and L1‐L3‐l5) were calculated. Neck angle, linear and temporal stride parameters and protraction‐retraction angles of the limbs were also calculated. Results: The vertical ROM (flexion‐extension) was similar in both conditions, but the horizontal ROM (lateral bending) of the lumbar angles T17‐L1‐L3 and L1‐L3‐L5 was less during T locomotion (mean ± s.d. difference of 1.8 ± 0.6 and 1.7 ± 0.9°, respectively, P>0.05). During O locomotion, the symmetry pattern of the lumbar vertebral angles was diminished from 0.9 to 0.7 (1 = 100% symmetry) indicating increased irregularity of the movement (P>0.05). No differences were found in the basic linear and temporal stride parameters and neck angle. Potential relevance: Vertebral kinematics during treadmill locomotion is not identical to over ground locomotion, but the differences are minor. During treadmill locomotion lumbar motion is less, and caution should be therefore taken when interpreting lumbar kinematics. 相似文献
958.
The prevalence of infections with different Brachyspira species was assessed in 202 pigs with various chronic herd problems using different methods. Twenty-seven pigs (13.4%) were positive for Brachyspira spp. with at least one of the methods used. The highest number of positives was identified with mucosal scraping-PCR (23), followed by PET-PCR (22) and bacteriological-biochemical analysis (15). With the exception of three cases of B. pilosicoli infections, only weakly pathogenic Brachyspira species were identified. The majority was B. murdochii, followed by B. innocens and B. intermedia. Concurrent infections with two or more Brachyspira species were common and accounted for 37.1% of the total. Presence of weakly haemolytic Brachyspira was associated with wasting and diarrhoea in a number of cases. This investigation shows that infections with weakly haemolytic Brachyspira spp. may contribute to colonic pathology in pigs with chronic herd problems and that mixed infections seem to occur more frequently than previously noticed. 相似文献
959.
Fecal shedding of infectious feline leukemia virus and its nucleic acids: a transmission potential 总被引:1,自引:0,他引:1
Gomes-Keller MA Gönczi E Grenacher B Tandon R Hofman-Lehmann R Lutz H 《Veterinary microbiology》2009,134(3-4):208-217
Although it is assumed that fecal shedding of feline leukemia virus (FeLV) constitutes a transmission potential, no study has been performed showing that feces of infected cats can be a source of infection. In this study, we investigated fecal viral shedding of FeLV and its role in viral pathogenesis with the goal to improve infection control. FeLV RNA and DNA levels were determined in rectal swabs of experimentally infected cats by real-time PCR, and the results were correlated with proviral and viral loads in whole blood and plasma, respectively, and plasma p27 levels. All antigenemic cats shed FeLV RNA and DNA in feces. To determine whether the viral RNA detected was infectious, virus isolation from feces was also performed. Infectious virus was isolated from feces of antigenemic cats, and these results perfectly correlated with the isolation of virus from plasma. Na?ve cats exposed to these feces seroconverted, showing that infection through feces took place, but remained negative for the presence of FeLV provirus and p27 in blood, an outcome so far not described. Some of the organs collected after euthanasia were provirus positive at low copy numbers. From these results it is concluded that fecal shedding of FeLV plays a role in transmission, but it is probably of secondary importance in viral pathogenesis. Nevertheless, sharing of litter pans by susceptible and viremic cats could increase the environmental infectious pressure and appropriate measures should be taken to avoid unnecessary viral exposure. 相似文献
960.
Döring D Roscher A Scheipl F Küchenhoff H Erhard MH 《Veterinary journal (London, England : 1997)》2009,182(1):38-43
To investigate further the occurrence of fear-related behaviour in dogs in veterinary practice and to evaluate associated factors, 135 dogs were observed under practice conditions within the framework of a standardised test examination and the owners interviewed using a questionnaire. Most dogs exhibited fear reactions, particularly on the examination table, with 78.5% (106/135) categorised as ‘fearful’ based on their behaviour. Unlike weight and castration, age, gender and previous experience were significantly (P < 0.05) associated with fearful behaviour. Male dogs were significantly less ‘fearful’ than females and animals under <2 years were significantly less ‘fearful’ compared with older dogs. Those with only positive previous experiences in veterinary surgeries were significantly less ‘fearful’ than dogs that had a previous negative experience. Fear-related behaviour in veterinary practice is an issue of importance. 相似文献