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151.
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Replicate clones of compatible cultivars of Populus deltoides and P. euramericana, grown for 3 months on a high (28/20°C - day/night) temperature regime and incubated, following inoculation with a mixture of urediniospores of six races of Melampsora medusae, on a high (28/20°C - light/dark) temperature regime, were more resistant (as determined by uredinial number) to leaf rust than those raised and incubated on any other combination of the high (28/20°C) and low (20/10°C) pre- and post-inoculation temperature regimes. Irrespective of the parameter employed to assess disease intensity, cultivar constitution and pre- and post-inoculation temperature are significant contributors to the level of disease induced in the cultivars by the isolate of M. medusae. The rating of cultivars for relative resistance is somewhat dependant on the parameter employed to assess disease, and for most parameters there are significant interactions of cultivar and pre- and post-inoculation temperature in determining the disease level induced. The coefficients of determination between the parameters of disease level are low, hence the results of the experiment are of limited value for extrapolation to field conditions. The possibility, in future investigations, of employing a disease parameter with more epidemiological significance is discussed. 相似文献
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Antony F. Machin Heather Rogers Alan J. Cross Michael P. Quick Laurence C. Howell Norman F. Janes 《Pest management science》1975,6(5):461-473
The phosphorothionate insecticide diazinon was incubated with liver microsomes from the sheep, cow, pig, guinea-pig, rat, turkey, chicken and duck. Metabolism by liver slices of most of these species was also examined. Hydroxydiazinon, isohydroxydiazinon, dehydrodiazinon, their oxons and diazoxon were identified and determined quantitatively or semi-quantitatively. An eighth metabolite was tentatively identified as the 6-aldehyde analogue of diazinon. Yields and rates of production of these metabolites varied greatly between species. Production of oxons was not generally correlated with susceptibility to diazinon poisoning, although it was lowest in the least susceptible animal, the sheep. The degradation of oxons by liver slices was too slow to explain the low toxicity of diazinon to the mammals. The relative importance of hepatic and extrahepatic metabolism in determining toxicity to vertebrates is discussed. 相似文献
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Seibert LM Crowell-Davis SL Wilson GH Ritchie BW 《Journal of the American Animal Hospital Association》2004,40(4):261-269
This double-blind, placebo-controlled trial was performed to evaluate the efficacy of clomipramine for the treatment of feather picking disorder in otherwise healthy cockatoos. Twenty cockatoos with chronic feather picking disorder were screened for medical conditions and then randomly assigned to either a clomipramine or placebo group. Based on caregiver assessments and physical examination findings, treatment with clomipramine significantly improved feather picking when compared to a placebo at 3 weeks (P=0.028) and at 6 weeks (P=0.021). Clomipramine had no significant effect, however, on videotaped preening behaviors. 相似文献
158.
Felicity Crotty Heather McCalman Huw Powell Sue Buckingham Christina Marley 《Soil Use and Management》2019,35(1):169-176
Perennial ryegrass starts growing when soil temperatures reach 5.5°C for five consecutive days; applying N fertilizer before this risks environmental losses. To test whether daffodil flowering signified when to apply N fertilizer, farmers volunteered to take part in a citizen science study. The PROSOIL project used a “citizen science”, participatory approach to create farmer‐informed science, aiming to increase awareness of the importance of soil health. In 2014, over 300 farmers completed a “How do you manage your soil” survey. The survey included a question on the use of daffodils (Narcissus spp.) to indicate the best time to apply the first nitrogen fertilizer of the season, based on anecdotal feedback from farmers involved in the PROSOIL project. The survey recorded 7% of farmers based their first fertilizer application on when daffodils flowered. To increase farmer awareness of soil temperatures, we provided them with soil thermometers, held workshops and hosted interactive stands at agricultural events in 2014. In autumn 2014, farmers planted daffodil bulbs of the same variety, across Wales, and monitored soil temperatures. Farmers returned postcards once their daffodils were in flower, noting the soil temperature. An assessment of whether daffodil flowering date could indicate when to apply N fertilizer was made. Overall, in spring 2015, daffodils flowered when soil temperature was 6.4(±0.35)°C, suggesting daffodil flowering date is a more reliable indicator for fertilizer application, than first hypothesized. Findings show a scientific validation of local knowledge, regarding the use of daffodils to indicate the “not‐before” date for the first N fertilizer application. 相似文献
159.
Negative attitudes toward invertebrates are a deep-seated, visceral response among Western peoples. These internalized aversions toward insects and other terrestrial arthropods, both in general and specifically as a food source, subtly and systemically contribute to unsustainable global foodways. Insect cuisine is, for Westerners, emblematic of the alien, a threat to our psychological and cultural identity. Yet failure to embrace entomophagy prevents us from seeing the full humanity of those of other classes, races, and cultures, and leads to agricultural and food policy decisions that fail in their objectives to improve nourishment for all people. Key to enabling the world’s peoples to live sustainably with the land are: (1) awareness of the psychological and cultural barriers to a more insect-positive perspective (2) embracing insects as a desirable food resource, (3) understanding the processes by which those barriers are constructed, their negative consequences, and (4) identifying strategies for transforming our attitudes. 相似文献
160.
Bridget C. Garner Heather Priest Jo Smith 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2014,43(2):266-269
A 10‐year‐old spayed female Miniature Poodle was presented to the University of Georgia veterinary teaching hospital for evaluation of lethargy, vomiting and anorexia of 4 days' duration. Physical examination, history and a minimum database led to a diagnosis of immune‐mediated hemolytic anemia accompanied by marked hyperbilirubinemia. Refractometric protein determination was within the reference interval, whereas the biuret method indicated hypoproteinemia. This discrepancy was attributed to interference of bilirubin and biliverdin with the spectrophotometric read‐out of the biuret total protein assay. The albumin concentration, determined by bromcresol green, and refractometric total protein were less affected by this interference. 相似文献