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Hematological traits are essential parameters for veterinary practice to quantify health status of individuals and herds. A major problem with the interpretation of hematological values is their pronounced variability that is to a great extend caused by non-systematic factors. Differences in breeds and populations are providing evidence for different genotypes in this regard, although there is no information available in swine about the nature and shares of participating genes. Goal of the present paper was to evaluate the additive-genetic share of total variability of traits of the red and white blood cell count. The results are based on 139 F2-pigs of a Pietrain-Meishan-family. Medium to high heritabilities have been estimated for the numbers of neutrophiles, the mean corpuscular hemoglobin concentration and the hemoglobin content, and for the shares of basophile granulocytes, platelets and lymphocytes. No meaningful shares of additive genetic variance were obvious in the other traits. Shares of additive genetic variance of the above mentioned traits argue for the existence of favourable and unfavourable gene variants to be involved in their phenotypic variation. Isolation of these variants might improve the diagnostical use of those traits in the future and provide a measure to advance general health in the pig. 相似文献
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Frauke Kleemann Maximilian von Fragstein Barbara Vornam Annika Müller Christoph Leuschner Andrea Holzschuh Teja Tscharntke Reiner Finkeldey Andrea Polle 《European Journal of Forest Research》2011,130(5):707-716
Knowledge on phenological, morphometric, and phytochemical variation of local progenies of European aspen (Populus tremula, L.) is limited. The goal of this study was to characterize variation in growth and ecologically important leaf properties
in aspen full-sib families in relation to interacting organisms (mycorrhiza, endophytes, and insects) and to determine whether
these interactions were affected by soil application of a systemic fungicide. In local progenies, within-family variation
of neutral molecular genetic markers (nuclear microsatellites) was higher than between families. Significant variation in
growth, production of phenolic defensive compounds and other phytochemical leaf traits was found between families. Phenolic
compounds showed clear negative correlation with generalist herbivores, but did not result in negative trade-off with biomass
production. Differences in mycorrhizal colonization were not found among full-sib families and application of a systemic fungicide
suppressed neither mycorrhizal colonization nor infestation with insects. However, a strong suppression of endophytes occurred,
whose long-term consequences may require attention when fungicides are used in agroforestry plantations. 相似文献
25.
Madhav Pandey Oliver Gailing Hans H. Hattemer Reiner Finkeldey 《European Journal of Forest Research》2012,131(3):739-746
Knowledge of SGS in plants is vital to understand the ecological and evolutionary dynamics of populations and to plan conservation
strategies. Some of the major factors that can affect spatial genetic structure (SGS) in plants are the level of gene flow,
spatial arrangement and life stages of individuals within populations. Applying six highly variable microsatellite markers,
we investigated the effect of these factors on spatial genetic structure selecting two natural populations of sycamore maple,
which is an insect-pollinated, autotetraploid and an indigenous hardwood species in Germany and in other central European
countries. The two study populations had different shapes (“compact” and “elongated”) and tree densities. Significant SGS
extended to ~180 m in the elongated population and to ~35 m in the compact population. Juvenile plants of the compact population
showed significant SGS up to 40 m. Estimate of Sp statistic in high-density population was almost double of that in the population
with low density. Gene dispersal distance in the low-density population was about 9 times higher than in the population with
high density. The similar level of significant SGS in both adult and juvenile plants suggested minimal or no effect of life
stages of individuals on SGS in the sycamore maple population. The data presented in this study can provide guidelines for
seed collection and to establish populations for the conservation and management of genetic resources of the species. 相似文献
26.
Marie Reimer Clara Kopp Tobias Hartmann Heidi Zimmermann Reiner Ruser Rudolf Schulz Torsten Müller Kurt Möller 《植物养料与土壤学杂志》2023,186(2):217-233
Background
Fertilization with organic waste compost can close the nutrient cycles between urban and rural environments. However, its effect on yield and soil fertility must be investigated.Aim
This study investigated the long-term effect of compost on soil nutrient and potentially toxic elements (PTEs) concentration, nutrient budgets, and nitrogen (N) mineralization and efficiency.Methods
After 21 years of annual compost application (100/400 kg N ha–1 year–1 [100BC/400BC]) alone and combined with mineral fertilization, soil was analyzed for pH, organic carbon (SOC), nutrient (total N and P, Nmin, extractable CAL-P, CAL-K, and Mg), and PTE (Cu, Ni, Zn) concentrations. Yields were recorded and nutrient/PTE budgets and apparent net mineralization (ANM, only 2019) were calculated.Results
N efficiency was the highest in maize and for mineral fertilization. Compost application led to lower N efficiencies, but increased ANM, SOC, pH, and soil N, and surpluses of N, P, and all PTEs. Higher PTE concentrations were only found in 400BC for Cu. Nutrient budgets correlated with soil nutrient concentration. A surplus of 16.1 kg P ha–1 year–1 and 19.5 kg K ha–1 year–1 resulted in 1 mg kg–1 increase in CAL-P and CAL-K over 21 years.Conclusion
Compost application supplies nutrients to crops with a minor risk of soil-accumulation of PTEs. However, the nutrient stoichiometry provided by compost does not match crop offtakes causing imbalances. Synchronization of compost N mineralization and plant N demand does not match and limits the yield effect. In winter wheat only 65–70% of N mineralization occurred during the growth period. 相似文献27.
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Polycyclic Musks in Water, Sediment, and Fishes from the Upper Hudson River, New York, USA 总被引:1,自引:0,他引:1
Synthetic musks are used in many consumer products for their pleasant odor and their binding affinity for fabrics. In the early 1990s, polycyclic musks were reported to occur in air, water, sediment, wildlife, and humans from many European countries. Concentrations of polycyclic musks, particularly 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-[??]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN), have been reported to increase over time in the environment. In this study, concentrations of musks in water, sediment, fish, and mussel were determined from three locations along the upper Hudson River. HHCB and AHTN were detected in water (n?=?5; 3.95?C25.8 and 5.09?C22.8 ng/L, respectively), sediment (n?=?3; 72.8?C388 and 113?C544 ng/g, dry weight), fish (n?=?30; <1?C125 and <1?C32.8 ng/g, lipid weight), and zebra mussel (n?=?4; 10.3?C19.3 and 42.2?C65.9 ng/g, lipid weight) samples. Bioaccumulation factors of HHCB calculated for white perch, catfish, smallmouth bass, and largemouth bass were in the range of 18 to 371, when the concentrations in fish were expressed on a wet weight basis; the factors were in the range of 261 to 12,900, when the concentrations in fish were expressed on a lipid weight basis. 相似文献
30.
Comparisons of energy balance and evapotranspiration between flooded and aerobic rice fields in the Philippines 总被引:3,自引:0,他引:3
Ma. Carmelita R. Alberto Reiner Wassmann Takashi HiranoAkira Miyata Ryusuke HatanoArvind Kumar Agnes PadreModesto Amante 《Agricultural Water Management》2011,98(9):1417-1430
The seasonal and annual variability of sensible heat flux (H), latent heat flux (LE), evapotranspiration (ET), crop coefficient (Kc) and crop water productivity (WPET) were investigated under two different rice environments, flooded and aerobic soil conditions, using the eddy covariance (EC) technique during 2008-2009 cropping periods. Since we had only one EC system for monitoring two rice environments, we had to move the system from one location to the other every week. In total, we had to gap-fill an average of 50-60% of the missing weekly data as well as those values rejected by the quality control tests in each rice field in all four cropping seasons. Although the EC method provides a direct measurement of LE, which is the energy used for ET, we needed to correct the values of H and LE to close the energy balance using the Bowen ratio closure method before we used LE to estimate ET. On average, the energy balance closure before correction was 0.72 ± 0.06 and it increased to 0.99 ± 0.01 after correction. The G in both flooded and aerobic fields was very low. Likewise, the energy involved in miscellaneous processes such as photosynthesis, respiration and heat storage in the rice canopy was not taken into consideration.Average for four cropping seasons, flooded rice fields had 19% more LE than aerobic fields whereas aerobic rice fields had 45% more H than flooded fields. This resulted in a lower Bowen ratio in flooded fields (0.14 ± 0.03) than in aerobic fields (0.24 ± 0.01). For our study sites, evapotranspiration was primarily controlled by net radiation. The aerobic rice fields had lower growing season ET rates (3.81 ± 0.21 mm d−1) than the flooded rice fields (4.29 ± 0.23 mm d−1), most probably due to the absence of ponded water and lower leaf area index of aerobic rice. Likewise, the crop coefficient, Kc, of aerobic rice was significantly lower than that of flooded rice. For aerobic rice, Kc values were 0.95 ± 0.01 for the vegetative stage, 1.00 ± 0.01 for the reproductive stage, 0.97 ± 0.04 for the ripening stage and 0.88 ± 0.03 for the fallow period, whereas, for flooded rice, Kc values were 1.04 ± 0.04 for the vegetative stage, 1.11 ± 0.05 for the reproductive stage, 1.04 ± 0.05 for the ripening stage and 0.93 ± 0.06 for the fallow period. The average annual ET was 1301 mm for aerobic rice and 1440 mm for flooded rice. This corresponds to about 11% lower total evapotranspiration in aerobic fields than in flooded fields. However, the crop water productivity (WPET) of aerobic rice (0.42 ± 0.03 g grain kg−1 water) was significantly lower than that of flooded rice (1.26 ± 0.26 g grain kg−1 water) because the grain yields of aerobic rice were very low since they were subjected to water stress.The results of this investigation showed significant differences in energy balance and evapotranspiration between flooded and aerobic rice ecosystems. Aerobic rice is one of the promising water-saving technologies being developed to lower the water requirements of the rice crop to address the issues of water scarcity. This information should be taken into consideration in evaluating alternative water-saving technologies for environmentally sustainable rice production systems. 相似文献