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71.
Jonas Schler Dirk Hinrichs Georg Thaller 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(6):518-525
During last decades, native uniqueness decreased in local livestock breeds due to the introgression of high‐yielding breeds. Recovery of native uniqueness became important because of conservation aspects regarding native genetic diversity and native traits. Thereby the expectation exists, that the relation between native uniqueness and genetic gain is contradictory. The aim of this study was to explore the influence of native uniqueness on performance traits and the total merit index in a local red cattle breed from Northern Germany. Data contained a pedigree file of 178,255 Red Dual‐Purpose cattle, 809 target genotypes and 3,581 reference genotypes from introgressed breeds. Native genetic contributions were tested for correlation with performance traits of milk yield, longevity, foundation, somatic cells, fertility and maternal calving and the total merit index. The study revealed that native uniqueness is favourably related to longevity (0.16), foundation (0.23), and somatic cells (0.08), and the total merit index (0.10). Selection on native uniqueness could probably lead to an increased longevity, udder health and genetic gain of the Red Dual‐Purpose cattle. Moreover, it was shown that the Red Dual‐Purpose cattle was not upgraded through introgression of high‐yielding breeds. 相似文献
72.
Dirk Hoffmeister Guido Waldhoff Wolfgang Korres Constanze Curdt Georg Bareth 《Precision Agriculture》2016,17(3):296-312
Information on crop height, crop growth and biomass distribution is important for crop management and environmental modelling. For the determination of these parameters, terrestrial laser scanning in combination with real-time kinematic GPS (RTK–GPS) measurements was conducted in a multi-temporal approach in two consecutive years within a single field. Therefore, a time-of-flight laser scanner was mounted on a tripod. For georeferencing of the point clouds, all eight to nine positions of the laser scanner and several reflective targets were measured by RTK–GPS. The surveys were carried out three to four times during the growing periods of 2008 (sugar-beet) and 2009 (mainly winter barley). Crop surface models were established for every survey date with a horizontal resolution of 1 m, which can be used to derive maps of plant height and plant growth. The detected crop heights were consistent with observations from panoramic images and manual measurements (R2 = 0.53, RMSE = 0.1 m). Topographic and soil parameters were used for statistical analysis of the detected variability of crop height and significant correlations were found. Regression analysis (R2 < 0.31) emphasized the uncertainty of basic relations between the selected parameters and crop height variability within one field. Likewise, these patterns compared with the normalized difference vegetation index (NDVI) derived from satellite imagery show only minor significant correlations (r < 0.44). 相似文献
73.
Nodulation and root growth increase in lower soil layers of water‐limited faba bean intercropped with wheat 下载免费PDF全文
Below‐ground niche complementarity in legume–cereal intercrops may improve resource use efficiency and root adaptability to environmental constraints. However, the effect of water limitation on legume rooting and nodulation patterns in intercropping is poorly understood. To advance our knowledge of mechanisms involved in water‐limitation response, faba bean (Vicia faba L.) and wheat (Triticum aestivum L.) were grown as mono‐ and intercrops in soil‐filled plexiglass rhizoboxes under water sufficiency (80% of water‐holding capacity) and water limitation (30% of water‐holding capacity). We examined whether intercropping facilitates below‐ground niche complementarity under water limitation via interspecific root stratification coupled with modified nodulation patterns. While no significant treatment effects were measured in intercropped wheat growth parameters, water limitation induced a decrease in shoot and root biomass of monocropped wheat. Likewise, shoot biomass and height, and root length of monocropped faba bean significantly decreased under water limitation. Conversely, water limitation stimulated root biomass of intercropped faba bean in the lower soil layer (15–30 cm soil depth). Similarly, total nodule number of faba bean roots as well as nodule number in the lower soil layer increased under intercropping regardless of water availability. Under water limitation, intercropping also led to a significant increased nodule biomass (48%) in the lower soil layer as compared to monocropping. The enhanced nodulation in the lower soil layer and the associated increase in root and shoot growth provides evidence for a shift in niche occupancy when intercropped with wheat, which improves water‐limited faba bean performance. 相似文献
74.
Sabin Basi Juergen Burkhardt Georg Noga Mauricio Hunsche 《Weed Biology and Management》2014,14(3):186-197
The objective of this study was to better understand the role of chaotropic and kosmotropic salts in stomatal uptake, a process that occurs in parallel with cuticular penetration and affects the bioefficacy of glyphosate. In Trial 1, salt solutions of kosmotropic (NH4)2SO4 and chaotropic NaClO3, with or without the organosilicone surfactant, Break‐Thru® S233 (BT), and with or without glyphosate, were prepared. In Trial 2, sodium salts with a kosmotropic‐to‐chaotropic nature (Na2SO4, NaCl, NaNO3 or NaClO3) and BT were prepared with or without glyphosate. At very high concentrations, the salts of a kosmotropic nature induced a slight decrease in the surface tension, whereas those of a chaotropic nature triggered a significant decrease in the surface tension. Solution droplets were deposited onto the leaves of Viola arvensis and Chenopodium album. The dried deposits were analyzed with an environmental scanning electron microscope. The salts formed structures linking the exterior to the interior of the stomata in the crystalline ([NH4]2SO4) or amorphous (NaClO3) form. However, the low surface tension alone did not appear to be the unique driving force for stomatal uptake. With glyphosate, amorphous globular structures of glyphosate salt were formed in the Na2SO4 (kosmotropic) solution. Differently, the salts of a rather chaotropic nature (NaNO3 or NaClO3) formed a colloidal matrix. In general, salt residues were observed over the periclinal cell walls and inside the stomatal chamber. Neither (NH4)2SO4 nor Na2SO4 had a significant impact on glyphosate bioefficacy. However, the chaotropic salt, NaNO3, enhanced the bioefficacy of glyphosate the most, with a performance that was comparable to that of the solution glyphosate + organosilicone surfactant. 相似文献
75.
Spatial patterns of soil biological and physical properties in a ridge tilled and a ploughed Luvisol
Evelyn Müller Holger Wildhagen Michael Quintern Jürgen Heß Florian Wichern Rainer Georg Joergensen 《Soil & Tillage Research》2009,105(1):88-95
The present study was conducted to determine the spatial heterogeneity of bulk density, soil moisture, inorganic N, microbial biomass C, and microbial biomass N in the ridge tillage system of Turiel compared to conventional mouldboard ploughing on three sampling dates in May, July, and August. The soil sampling was carried out under vegetation representing the ridge in a high spatial resolution down the soil profile. Bulk density increased with depth and ranged from 1.3 g cm−3 at 10 cm depth to 1.6 g cm−3 at 35 cm in ploughed plots and from 1.0 g m−3 at 5 cm to 1.4 g m−3 at 35 cm in the ridges. In the ploughed plots, the contents of microbial biomass C and microbial biomass N remained roughly constant at 215 and 33 μg g−1 soil, respectively, throughout the experimental period. The microbial biomass C/N ratio varied in a small range around 6.4. In the ridged plots, the contents of microbial biomass C and microbial biomass N were 5% and 6% higher compared to the ploughed plots. Highest microbial biomass C contents of roughly 300 μg g−1 soil were always measured in the crowns in July. The lowest contents of microbial biomass C of 85–137 μg g−1 soil were measured in the furrows. The ridges showed strong spatial heterogeneity in bulk density, soil water content, inorganic nitrogen and microbial biomass. 相似文献
76.
Cornelia Adlhoch Alexander Wolf Helga Meisel Marco Kaiser Heinz Ellerbrok Georg Pauli 《Veterinary microbiology》2009,139(3-4):270-278
Swine Hepatitis E virus (HEV) can be transmitted from pigs to humans causing hepatitis. A high prevalence of HEV in wild boar populations is reported for several European countries, but actual data for Germany are missing. During the hunting season from October to December 2007 liver, bile and blood samples were collected from wild boars in four different German regions. The samples were tested for HEV RNA by quantitative PCR (qPCR) and anti-HEV IgG antibodies by two different ELISAs and a Line immunoassay. A seroprevalence of 29.9% using ELISA and 26.2% in the Line immunoassay was determined. The seroprevalence rate varied greatly within the analyzed regions. However, qPCR analysis revealed a higher prevalence of 68.2% positive animals with regional differences. Surprisingly, also adult wild sows and wild boars were highly HEV positive by qPCR. Compared to liver and serum samples, bile samples showed a higher rate of positive qPCR results. Sequencing and phylogenetic analysis of a 969 nt fragment within ORF 2 revealed that all isolates clustered within genotype 3 but differed in the subtype depending on the hunting spot. Isolates clustered within genotypes 3i, 3h, 3f and 3e. Within one population HEV isolates were closely related, but social groups of animals in close proximity might be infected with different subtypes. Two full-length genomes of subtypes 3i and 3e from two different geographic regions were generated. The wild boar is discussed as one of the main sources of human autochthonous infections in Germany. 相似文献
77.
78.
Greenhouse gas emissions in response to straw incorporation,water management and their interaction in a paddy field in subtropical central China 总被引:2,自引:0,他引:2
Cong Wang Hong Tang Kazuyuki Inubushi Georg Guggenberger 《Archives of Agronomy and Soil Science》2017,63(2):171-184
A field experiment was conducted to study the effects of combination of straw incorporation and water management on fluxes of CH4, N2O and soil heterotrophic respiration (Rh) in a paddy field in subtropical central China by using a static opaque chamber/gas chromatography method. Four treatments were set up: two rice straw incorporation rates at 0 (S1) and 6 (S2) t ha?1 combined with two water managements of intermittent irrigation (W1, with mid-season drainage) and continuous flooding (W2, without mid-season drainage). The cumulative seasonal CH4 emissions for the treatments of S1W2, S2W1 and S2W2 increased significantly by 1.84, 5.47 and 6.63 times, respectively, while seasonal N2O emissions decreased by 0.67, 0.29 and 1.21 times, respectively, as compared to S1W1 treatment. The significant increase in the cumulative Rh for the treatments S1W1, S2W1 and S2W2 were 0.54, 1.35 and 0.52 times, respectively, in comparison with S1W2. On a seasonal basis, both the CO2-equivalents (CO2e) and yield-scaled CO2e (GHGI) of CH4 and N2O emissions increased with straw incorporation and continuous flooding, following the order: S2W2>S2W1>S1W2>S1W1. Thus, the practices of in season straw incorporation should be discouraged, while mid-season drainage is recommended in paddy rice production from a point view of reducing greenhouse gas emissions. 相似文献
79.
Schäberle TF Goralski E Neu E Erol O Hölzl G Dörmann P Bierbaum G König GM 《Marine drugs》2010,8(9):2466-2479
Three myxobacterial strains, designated SWB004, SWB005 and SWB006, were obtained from beach sand samples from the Pacific Ocean and the North Sea. The strains were cultivated in salt water containing media and subjected to studies to determine their taxonomic status, the presence of genes for the biosynthesis of polyketides and antibiotic production. 16S rDNA sequence analysis revealed the type strain Enhygromyxa salina SHK-1(T) as their closest homolog, displaying between 98% (SWB005) and 99% (SWB004 and SWB006) sequence similarity. All isolates were rod-shaped cells showing gliding motility and fruiting body formation as is known for myxobacteria. They required NaCl for growth, with an optimum concentration of around 2% [w/v]. The G + C-content of genomic DNA ranged from 63.0 to 67.3 mol%. Further, the strains were analyzed for their potential to produce polyketide-type structures. PCR amplified ketosynthase-like gene fragments from all three isolates enhances the assumption that these bacteria produce polyketides. SWB005 was shown to produce metabolites with prominent antibacterial activity, including activity towards methicillin resistant Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE). 相似文献
80.
Georg Schirrmacher Thomas Skurk Hans Hauner Johanna Graßmann 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(1):71-76
Daily consumption of fruits and vegetables is frequently recommended to prevent several diseases. This health-promoting effect
is considered to be in part due to the antioxidant content of fruits and vegetables and their ability to decrease oxidative
stress. To investigate whether the ingestion of preparations from spinach or perilla, two carotenoid-rich leafy vegetables,
is followed by an increase in carotenoid concentration and/or affects parameters of oxidative stress in human blood plasma.
12 healthy volunteers ingested a perilla- or spinach preparation for 10 days (5 mg lutein/d). We quantified antioxidant levels
in plasma, kinetics of lipid peroxidation, MDA concentration, and total antioxidative capacity of plasma. We observed a significant
increase in lutein content and a moderate increase (n.s.) in β-carotene content in human blood plasma after consumption of
spinach or perilla. The markers of lipid peroxidation tended to decrease, but no influence on antioxidative capacity of plasma
could be detected. The high lutein content of perilla caused a more pronounced increase of lutein compared to spinach. Both
vegetables seem to be able to influence lipid peroxidation in a beneficial manner. 相似文献