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61.
Otolith Sr:Ca profiles demonstrated that juvenile anadromous brown trout (ABT) Salmo trutta may descend to the brackish waters of the Baltic Sea from their natal streams as parr or fry and then migrate into non‐natal streams before transforming into smolt. To our knowledge, no such published documentation exists for ABT. The ecological significance of this life‐history strategy is presently not clear. However, stream shifting through the marine environment should to be considered with regard to stock management and the assessment and restoration of salmonid populations and their potential habitats.  相似文献   
62.
Efficient utilization of various phosphorus (P) sources for producing optimum yields in P‐deficient conditions requires knowledge of best management under changing weather conditions. In this study, barley (Hordeum vulgare) was grown in an extremely P‐deficient soil with variable moisture conditions. During a wet growing period, utilization of P from dairy cow manure (DCM), fox manure (FM) and meat and bone meal (MBM) was compared with the utilization of P from superphosphate (SP) with concomitant effects on grain yield and quality. High P application rates were necessary to compensate for severe yield losses due to waterlogging. Only 7 kg P/ha was required for optimum yield in less waterlogged conditions, while 43 kg P/ha was needed in waterlogged conditions. In both moisture conditions, broadcast DCM‐P increased grain yield similar to banded SP‐P, although P acquisition was lower in early growth stages. FM‐P and MBM‐P were less efficiently utilized. Waterlogging also depressed yield quality when P was applied. Extreme rainfall events are predicted to become more frequent at northern latitudes. As an alternative to higher P fertilizer rates, improving soil drainage could be a favourable, long‐term measure for better utilization of applied P and soil P resources, even at very low soil P status.  相似文献   
63.
ObjectiveTo investigate MK-467 as part of premedication in horses anaesthetized with isoflurane.Study designExperimental, crossover study with a 14 day wash-out period.AnimalsSeven healthy horses.MethodsThe horses received either detomidine (20 μg kg−1 IV) and butorphanol (20 μg kg−1 IV) alone (DET) or with MK-467 (200 μg kg−1 IV; DET + MK) as premedication. Anaesthesia was induced with ketamine (2.2 mg kg−1) and midazolam (0.06 mg kg−1) IV and maintained with isoflurane. Heart rate (HR), mean arterial pressure (MAP), end-tidal isoflurane concentration, end-tidal carbon dioxide tension, central venous pressure, fraction of inspired oxygen (FiO2) and cardiac output were recorded. Blood samples were taken for blood gas analysis and to determine plasma drug concentrations. The cardiac index (CI), systemic vascular resistance (SVR), ratio of arterial oxygen tension to inspired oxygen (PaO2/FiO2) and tissue oxygen delivery (DO2) were calculated. Repeated measures anova was applied for HR, CI, MAP, SVR, lactate and blood gas variables. The Student's t-test was used for pairwise comparisons of drug concentrations, induction times and the amount of dobutamine administered. Significance was set at p < 0.05.ResultsThe induction time was shorter, reduction in MAP was detected, more dobutamine was given and HR and CI were higher after DET+MK, while SVR was higher with DET. Arterial oxygen tension and PaO2/FiO2 (40 minutes after induction), DO2 and venous partial pressure of oxygen (40 and 60 minutes after induction) were higher with DET+MK. Plasma detomidine concentrations were reduced in the group receiving MK-467. After DET+MK, the area under the plasma concentration time curve of butorphanol was smaller.Conclusions and clinical relevanceMK-467 enhances cardiac function and tissue oxygen delivery in horses sedated with detomidine before isoflurane anaesthesia. This finding could improve patient safety in the perioperative period. The dosage of MK-467 needs to be investigated to minimise the effect of MK-467 on MAP.  相似文献   
64.
65.
Ideotypes are a popular concept for plant breeders, who designate as such the ideal combinations of traits in a particular genotype to reach a pre-set production objective within a given socio-economic context. The historical, ‘genetic’ view of ideotypes has been more recently extended to cover the design of plant genotypes for specific cropping systems (the ‘agronomic’ view), or even the ideal combination of parameters, identified from formal or simulation modeling, to a specific agronomic problem (the ‘modelling’ view). These different forms of ideotypes in turn lead to different strategies for breeding plants. This paper will briefly describe, analyse and discuss some applications of these ideotype views, using the specific case of architectural traits of plant and crop canopies to limit the epidemic development of pests and diseases in crops. It is not intended to be an exhaustive and objective review of the existing literature on plant ideotypes, but rather to express as an ‘opinion’ paper the views discussed and elaborated among participants to the EpiArch network.  相似文献   
66.
The long-term effects of an overall foliar paclobutrazol application (750 mg a. i. per tree) was tested on sweet cherry spur growth and fruiting. Leaves and fruits were counted on spurs situated on long upright shoots, during the year of treatment and in the following two years. Paclobutrazol significantly increased the mean number of leaves per spur during the three year study. It also significantly increased the number of fruits per spur on three year old spurs, whereas no differences were observed on two year old spurs. Furthermore, the chemical treatment led to a significant increase in the number of fruits per corymb at the base of one year old long shoots. Otherwise, paclobutrazol appeared to induce spur ramification in the year of treatment. The same year, these ramifications, which did not bear fruits, accounted for 16.5% of the total number of spur leaves. This phenomenon was probably due to a direct action of the chemical spray since almost no new ramifications were produced the following years. In addition to the known retardation of extension shoot growth, foliar application of paclobutrazol thus appeared effectively to enhance leaf and fruit production of the spurs, not only in the year of treatment but also during the two following years.  相似文献   
67.
Two genes of wheat low-molecular-weight glutenin subunits (LMW-GS), B16 and P73, were cloned and expressed in E. coli. They were homologous to proteins encoded respectively at Glu-B3 and Glu-D3 loci. The N-terminal and C-terminal halves of B16 (NB16 and B16C) and the two chimeras combining the halves of the two genes (B16-P73 and P73- B16) were also expressed. All these constructs were compared for their reactivity with IgE from 24 patients suffering from different forms of wheat allergies. The results confirmed that LMW-GSs bound IgE in all adult allergies tested. Strong differences in reactivity between all the constructs were observed. They were disease-dependent. In wheat-dependent exercise-induced anaphylaxis (WDEIA), the reactivity of the constructs depended partly on common epitopes with omega-5 gliadins but also on differences in molecule conformation. The presence of NB16 in the constructs greatly influenced their IgE reactivity.  相似文献   
68.
Summary

Inflorescences are known to be important physiological sinks especially when they set fruit. The effect, over two successive years, of inflorescence removal on one year old wood was investigated on apple (Malus domestica Borkh.). The study was carried out on medium vigour (around 30 cm) branches of cv. Granny Smith. On one set of branches (control) the inflorescences were untreated, while on two other sets, one-third and two-thirds of inflorescences (spur leaves, bourse-shoot and flower cluster) were removed at full bloom. The first analysis investigated the fruit setting ability of remaining inflorescences. The results generally confirmed previous results on the positive correlation between the number of leaves and flowers of the inflorescence and fruit set, and also the higher fruit set on two year old wood as compared with one year old wood. On one year old wood, inflorescence removal treatments tended to increase the fruit set of inflorescences with a low number of leaves and flowers leading to a level of fruit set similar to that of inflorescences with a larger number of leaves and flowers. On two year old wood, in the following year, only the two-thirds treatment increased fruit set consistently compared with the control. A second analysis investigated the effect of inflorescence removal on lateral shoot development. It was shown that the treatments had a little effect on quantitative growth (length, diameter) of the laterals per se. On the other hand, the removal of two-thirds of the inflorescence significantly stimulated the development of fruitful inflorescences the following year. Results are discussed in relation to the local versus global physiological integration at the branch level.  相似文献   
69.
Projected changes in forest carbon stocks and carbon balance differ according to the choice of estimation methods and the carbon pools considered. Here, we compared three carbon assessment methods for optimizing timber production and carbon sequestration in six example Scots pine (Pinus sylvestris L.) stands in Finland. The forest carbon stock was assessed, with three methods: stem carbon, biomass expansion factors (BEFs), and a process-based model. Given a carbon price of 40 € t−1 (equivalent to 10.9 € t−1 CO2) and a 3% discount rate, the highest average carbon stock and mean annual increment (MAI) were obtained with the BEF method. Increasing the carbon price from 0 to 200 € t−1 resulted in longer optimal rotations and higher MAI, and increased the average carbon stock, especially when carbon was assessed by the BEF method. Comparison of these carbon assessment methods, using economic sensitivity analyses, indicated that optimal thinning regimes and average carbon stocks are strongly dependent on the assessment method. The process-based method led to less frequent thinnings and shorter rotations than the BEF method, due to different predictions of biomass production. As a cost-effective option, optimal thinning regimes play a very important role in timber production and carbon sequestration.  相似文献   
70.
The effects of silviculture on wood and tracheid properties, and economic returns of Norway spruce (Picea abies (L.) Karst.) were investigated in two case studies, one comparing different thinning intensity in southeastern Finland and the other considering the effects of optimal nutrient addition in northern Sweden. Models for predicting the wood and tracheid properties of Norway spruce were integrated into a distance-independent process-based growth and yield model. Increasing the thinning intensity resulted in a lower mean wood density, tracheid length, and latewood proportion in harvested wood. Wood density and tracheid length of harvested pulpwood slightly decreased in later thinnings and final cuts. Thinning regimes with high early growing stock and decreasing later growing stock were most profitable. Nutrient addition accelerated volume growth and increased the value growth. The increase in volume growth due to nutrient addition more than offset the economic influence of the loss in wood density and tracheid length.  相似文献   
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