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1.
Boulanger Yan Arseneault Dominique Boucher Yan Gauthier Sylvie Cyr Dominic Taylor Anthony R. Price David T. Dupuis Sébastien 《Landscape Ecology》2019,34(1):159-174
Landscape Ecology - Forest landscapes at the boreal–temperate ecotone have been extensively altered. Reducing the gap between current and presettlement forest conditions through... 相似文献
2.
Zhai Changyuan Long John Taylor Randal Weckler Paul Wang Ning 《Precision Agriculture》2020,21(3):589-602
Precision Agriculture - With recent developments allowing increased planter speeds, improving spatial uniformity of crop emergence will continue to be an important focus of research. Vertical... 相似文献
3.
Ray blight caused by Stagonosporopsis tanaceti is one of the most important diseases of pyrethrum (Tanacetum cinerariifolium), a perennial herbaceous plant cultivated for the extraction of insecticidal pyrethrins in Australia. The disease is responsible for complete yield loss in severe outbreaks. Infected seed is considered as the principal source of S. tanaceti. Infection hyphae remain only in the seed coat and not in the embryo, resulting in pre- and post-emergence death of seedlings and latent infection. Therefore, quantification of the level of infection by S. tanaceti within seed using a qPCR assay is important for efficient management of the disease. Stagonosporopsis tanaceti completes its life cycle within 12 days after leaf infection through production of pycnidia and can infect every tissue of the pyrethrum plant except the vascular and root tissues. Ray blight epidemics occur in pyrethrum fields through splash dispersal of pycnidiospores between adjacent plants. Besides steam sterilization, thiabendazole/thiram and fludioxonil are effective seed-treating chemicals in controlling S. tanaceti before planting begins. Ray blight is currently managed in the field through the foliar application of strobilurin fungicides in the first 1–2 years of crop establishment. Later on, difenoconazole and multisite specific fungicides in the next 2–3 years during early spring successfully reduce ray blight infestation. Avoiding development of resistance to fungicides will require more sustainable management of ray blight including the development and deployment of resistant cultivars. 相似文献
4.
A.M. Taylor L.E. Heflin M.L. Powell A.L. Lawrence S.A. Watts 《Aquaculture Nutrition》2017,23(2):375-386
In experiment 1, juvenile sea urchins (n = 80, 0.088 ± 0.001 g wet weight and 5.72 ± 0.04 mm diameter) were held individually and fed ad libitum one of three semi‐purified formulated diets (n = 16 individuals treatment?1). In the diets, protein was held constant (310 g kg?1 dry, as fed) and carbohydrate level varied (190, 260, or 380 g kg?1 dry, as fed). Wet weights were measured every 2 weeks. Total wet weight gain was inversely proportional to dietary carbohydrate level and energy content of the respective diet. In experiment 2, sea urchins (5.60 ± 0.48 g wet weight, n = 40) fed 190 g kg?1 carbohydrate consumed significantly more dry feed than those fed 260 g kg?1, but not more than those fed 380 g kg?1 carbohydrate. Based on differential feed intake rates, sea urchins that consumed more feed also consumed higher levels of protein and had the highest weight gain. Consequently, protein content and/or protein: energy ratio may be important in determining feed utilization and growth among sea urchins in this study. The average digestible energy intake was approximately 70 kcal kg?1 body weight day?1, suggesting daily caloric intake of juvenile Lytechinus variegatus is lower than in shrimp and fish. 相似文献
5.
Rapid salinity changes affect the survival and physiology of a penaeid prawn: Implications of flood events on recruitment to the fishery 下载免费PDF全文
K. J. Tyler A. Becker N. A. Moltschaniwskyj M. D. Taylor 《Fisheries Management and Ecology》2017,24(6):478-487
Estuaries act as nurseries for many penaeid prawns, but these habitats are highly susceptible to salinity decline through flooding. The rate of salinity decline and duration of exposure to non‐optimal salinity may affect survival and subsequent recruitment of prawns to the fishery. This study aimed to determine the effect of salinity fluctuations observed in local estuaries during flood events using a novel dilution approach. Mortality of juvenile Melicertus plebejus (Hess) was assessed after 24 hr exposure to 24 rates of salinity decline ranging from 0.01% to 20% per hr. After the salinity decline, prawns were held at the final salinities for five days before again assessing mortality as well as aerobic metabolic rate and prawn water content. Salinity decline from 36 to ~0.8 led to 50% mortality, but continued exposure to low salinity for five days increased mortality at this salinity to 99% and shifted the 50% mortality point to salinity ~5. Aerobic metabolic rate and water content data suggested the cause of mortality due to exposure to salinities < 5 was osmoregulatory failure. Rapid salinity declines over 24 hr and sustained low salinity due to flooding could compromise the survival of juvenile prawns, potentially reducing recruitment to the fishery. 相似文献
6.
Farnaz Kordbacheh Charles L. Mohler Alan G. Taylor Anna S. Westbrook Hamid Rahimian-Mashhadi Hassan M. Alizadeh Antonio DiTommaso 《Weed Research》2023,63(1):34-44
Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti. 相似文献
7.
L. H. Taylor L. Knopf the Partners for Rabies Prevention 《Zoonoses and public health》2015,62(7):543-552
Effective prevention of deaths due to human rabies is currently hampered by a lack of understanding of the scale of the problem, and the distribution of both animal and human cases across countries, regions and continents. Unfortunately, despite the severity of the disease, accurate data on which to assess these questions and to prioritize and direct public health interventions are not available for many parts of the world. This survey sought to understand the current global situation regarding the surveillance of human rabies. Data were collected from 91 countries across all continents and all categories of human rabies risk, generating the most complete and representative global data set currently available. Respondents were asked key questions about whether human rabies was a notifiable disease, how the surveillance system for human rabies operated and whether the respondent considered that the surveillance system was working effectively. Across the 91 countries from which data were collated, human rabies was a notifiable disease in all but eight. Despite international guidance, surveillance systems were very varied. Even where rabies is a notifiable disease, many countries had surveillance system judged to be ineffective, almost all of these being high and moderate rabies risk countries in Africa and Asia. Overall, 41% of the population covered by this survey (around 2.5 billion people) live in countries where there is no or ineffective rabies surveillance. The lack of robust surveillance is hindering rabies control efforts. However, whilst worldwide rabies surveillance would be improved if rabies were notifiable in all countries, many other challenges to the implementation of effective global human rabies surveillance systems remain. 相似文献
8.
9.
Sophie St-Hilaire Derek Price Shawna Taylor David Groman 《The Canadian veterinary journal. La revue veterinaire canadienne》2015,56(8):876-878
Rainbow trout (average weight of 2 g) in fresh water experienced high mortality and were infected with a diplomonad intestinal parasite. Tanks of fish experienced an immediate reduction in mortality after an in-feed treatment with 3% Epsom salts for 2 d. Treatments had to be applied several times, but in each case there was a similar reduction in mortality. 相似文献