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11.
Paakkonen T Mustonen AM Käkelä R Kiljander T Kynkäänniemi SM Laaksonen S Solismaa M Aho J Kortet R Puukka K Saarela S Härkönen L Kaitala A Ylönen H Nieminen P 《Veterinary parasitology》2011,179(1-3):180-188
The deer ked (Lipoptena cervi) is a haematophagous parasitic fly of cervids that spread to Finland in the early 1960's. Presently its northern distribution limit lies at approximately 65°N and it is gradually spreading northwards. In Finland the principal host species has been the moose (Alces alces), but the deer ked is about to establish contact with another potential host, the semi-domesticated reindeer (Rangifer tarandus tarandus) causing possible threats to reindeer health and management. The aim of this study was to investigate if the deer ked would have an influence on the welfare of the reindeer. Eighteen adult reindeer were divided into three experimental groups: the control group and two infected groups with 300 deer keds per reindeer introduced in August-September. One of the infected groups was treated with subcutaneous ivermectin in November. To gather comprehensive data on potential health hazards caused by the deer ked a wide array of physiological variables was measured during and at the end of the experiment in December. The keds caused no clear changes in the complete blood count, plasma clinical chemistry, amino acids, endocrinology, energy stores, enzyme activities or tissue fatty acid profiles of the host. The haematological, clinical chemical and endocrinological values displayed changes that could be related to the seasonal physiological adaptations of the species. In conclusion, at the duration and intensity of infection that were employed, the effects of the deer ked on the measured physiological variables of the reindeer were insignificant. 相似文献
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Hamid Khazaei Kenneth Street Arja Santanen Abdallah Bari Frederick L. Stoddard 《Genetic Resources and Crop Evolution》2013,60(8):2343-2357
Drought is a major constraint to faba bean (Vicia faba L.) production, and there are many mechanisms by which leaves can regulate water loss. Our primary objective was to test if the origin of the faba bean accessions, from drought-prone and non-drought-prone environments, was associated with differences in measurable aspects of stomatal morphology and physiology related to water use. Two sets, each consisting of 201 faba bean accessions, were chosen from environments with contrasting seasonal moisture profiles following the focused identification of germplasm strategy (FIGS), and then screened under well watered conditions. From these, two subsets of 10 accessions each were chosen to test for differences in response to drought. Parameters related to stomatal function and water status were measured. The dry-adapted set had bigger stomata, higher leaf relative water content (LRWC) and cooler leaves under well watered conditions. Stomatal density and stomatal area per unit area of leaflet were negatively correlated with gas exchange parameters and positively correlated with intrinsic water use efficiency. Drought caused stomatal densities to increase in the dry set while stomatal length decreased in both sets. The moisture deficit was sufficient to decrease gas exchange in both sets to similar levels, but the dry-adapted set maintained warmer leaves and a higher LRWC that showed no significant correlations with leaf morphology or gas exchange, demonstrating more effective stomatal regulation. The results also support that collection site data from the environment where genetic resources are collected can be used as indicators of adaptive traits in an herbaceous annual species. 相似文献
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Laitila A Sweins H Vilpola A Kotaviita E Olkku J Home S Haikara A 《Journal of agricultural and food chemistry》2006,54(11):3840-3851
Lactobacillus plantarum VTT E-78076 (E76) and Pediococcus pentosaceus VTT E-90390 (E390) starter cultures were added to the steeping water of normal malting barley in order to balance the microbial community and to enhance malt processability. In this study, we also investigated the effects of lactic acid-acidified MRS-spent medium (MRS-LA) on malting performance. Malting trials with five different two-row barley varieties were carried out in 25 kg pilot scale. The starter cultures promoted yeast growth during malting and restricted the growth of harmful bacteria and Fusarium fungi. Furthermore, they had positive effects on malt characteristics. Reduction in wort viscosity and beta-glucan content and enhanced xylanase and microbial beta-glucanase activities were observed. Starter cultures notably improved lautering performance. Some of the beneficial effects were due to the lactic acid and low pH, as similar effects were obtained with MRS-LA. Starter cultures offer a tool for tailoring of malt properties. 相似文献
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J Riikonen S Kontunen-Soppela V Ossipov A Tervahauta M Tuomainen E Oksanen E Vapaavuori J Heinonen M Kivimäenpää 《Tree physiology》2012,32(9):1102-1112
Northern forests are currently experiencing increasing mean temperatures, especially during autumn and spring. Consequently, alterations in carbon sequestration, leaf biochemical quality and freezing tolerance (FT) are likely to occur. The interactive effects of elevated temperature and ozone (O(3)), the most harmful phytotoxic air pollutant, on Norway spruce (Picea abies (L.) Karst.) seedlings were studied by analysing phenology, metabolite concentrations in the needles, FT and gas exchange. Sampling was performed in September and May. The seedlings were exposed to a year-round elevated temperature (+1.3 °C), and to 1.4× ambient O(3) concentration during the growing season in the field. Elevated temperature increased the concentrations of amino acids, organic acids of the citric acid cycle and some carbohydrates, and reduced the concentrations of phenolic compounds, some organic acids of the shikimic acid pathway, sucrose, cyclitols and steroids, depending on the timing of the sampling. Although growth onset occurred earlier at elevated temperature, the temperature of 50% lethality (LT(50)) was similar in the treatments. Photosynthesis and the ratio of photosynthesis to dark respiration were reduced by elevated temperature. Elevated concentrations of O(3) reduced the total concentration of soluble sugars, and tended to reduce LT(50) of the needles in September. These results show that alterations in needle chemical quality can be expected at elevated temperatures, but the seedlings' sensitivity to autumn and spring frosts is not altered. Elevated O(3) has the potential to disturb cold hardening of Norway spruce seedlings in autumn, and to alter the water balance of the seedling through changes in stomatal conductance (g(s)), while elevated temperature is likely to reduce g(s) and consequently reduce the O(3)-flux inside the leaves. 相似文献
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Sirkka Juhanoja Minna Heikkilä Arja Virtanen 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(2):113-127
Fifty clones of the genera Forsythia, Hydrangea, Lonicera, Philadelphus and Viburnum were cultivated in comparative field trials at five sites in Finland in 1989–93. The aim was to find the hardiest and the most valuable clones to be recommended for landscape gardening. The evaluation covered about 30 traits which were recorded annually. Most attention was paid to winter‐hardiness, resistance to diseases and pests, and ornamental value. The data were analysed using both statistical and non‐statistical methods. A combination of these proved to be a successful method for selecting the clones with the highest value for production. Nine clones were selected as recommendable clones. The Hydrangea paniculata cultivars ‘Grandiflora’, ‘Praecox’ and ‘Mustila’ were found to be valuable and recommendable. Several Lonicera clones succeeded well and were renamed. Three clones were selected as being suitable for different purposes: L. tatarica ’Sanna’ suits well for hedges, L. x bella ’Dropmore’ is white‐flowered, and L. x bella ’Sakura’ has a special growth habit. A true‐to‐type Philadelphus pubescens clone was renamed ‘Tuomas’ and an abundantly blossoming and hardy P. lewisii hybrid was renamed ‘Tähtisilmä’. Finnish Viburnum opulus clones representing a hardy type with plenty of blossoms were renamed ‘Pohjan Neito’. 相似文献