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1.
2.
Ramona Weishaar Robin Wellmann Amelia Camarinha-Silva Markus Rodehutscord Jörn Bennewitz 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2020,137(1):14-22
Most traits in animal breeding, including feed efficiency traits in pigs, are affected by many genes with small effect and have a moderately high heritability between 0.1 and 0.5, which enables efficient selection. Since the microbiota composition in the gastrointestinal tract is also partly heritable and was shown to have a substantial effect on feed efficiency, the host genes affect the phenotype not only directly by altering metabolic pathways, but also indirectly by changing the microbiota composition. The effect of the microbiota composition on the breeding value of an animal is the conditional expectation of its breeding value, given the vector with microbiota frequencies, that is The breeding value of an animal can therefore be decomposed into a heritable contribution that arises from an altered microbiota composition and a heritable contribution that arises from altered metabolic pathways within the animal, so Instead of selecting for breeding value , an index comprising the two components and with appropriate weights, that is , can be used. The present study shows how this breeding strategy can be applied in pig genomic selection breeding scheme for two feed efficiency traits and daily gain. 相似文献
3.
Stefan Möth Markus Redl Silvia Winter Florian Hüttner Siegrid Steinkellner 《Pest management science》2023,79(9):3080-3089
BACKGROUND
A reduction in chasmothecia, an important inoculum of grape powdery mildew (Erysiphe necator Schwein.), is essential for disease control in vineyards; the use of fungicides during the formation of chasmothecia on vine leaves, late in the growing season, may accomplish this. Inorganic fungicides, such as sulphur, copper, and potassium bicarbonate, are very useful for this purpose because of their multisite mode of action. The aim of this study was to evaluate chasmothecia reduction using different fungicide applications late in the growing season in commercially managed vineyards and in an exact application trial.RESULTS
Chasmothecia on vine leaves were reduced in commercial vineyards by four copper (P = 0.01) and five potassium bicarbonate (P = 0.026) applications. The positive effect of potassium bicarbonate was also confirmed in the application trial, where two applications showed lower chasmothecia numbers than the control (P = 0.002).CONCLUSION
The application of inorganic fungicides reduced the amount of chasmothecia as the primary inoculum source. Potassium bicarbonate and copper are of further interest for disease control as these fungicides can be used by organic and conventional wine growers. The application of these fungicides should be carried out as late as possible before harvest to reduce chasmothecia formation and, consequently, the potential for powdery mildew infestation in the subsequent season. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献4.
5.
Anja Hartmann Kathrin Becker Ulf Karsten Daniel Remias Markus Ganzera 《Marine drugs》2015,13(10):6291-6305
Mycosporine-like amino acids (MAAs), a group of small secondary metabolites found in algae, cyanobacteria, lichens and fungi, have become ecologically and pharmacologically relevant because of their pronounced UV-absorbing and photo-protective potential. Their analytical characterization is generally achieved by reversed phase HPLC and the compounds are often quantified based on molar extinction coefficients. As an alternative approach, in our study a fully validated hydrophilic interaction liquid chromatography (HILIC) method is presented. It enables the precise quantification of several analytes with adequate retention times in a single run, and can be coupled directly to MS. Excellent linear correlation coefficients (R2 > 0.9991) were obtained, with limit of detection (LOD) values ranging from 0.16 to 0.43 µg/mL. Furthermore, the assay was found to be accurate (recovery rates from 89.8% to 104.1%) and precise (intra-day precision: 5.6%, inter-day precision ≤6.6%). Several algae were assayed for their content of known MAAs like porphyra-334, shinorine, and palythine. Liquid chromatography-mass spectrometry (LC-MS) data indicated a novel compound in some of them, which could be isolated from the marine species Catenella repens and structurally elucidated by nuclear magnetic resonance spectroscopy (NMR) as (E)-3-hydroxy-2-((5-hydroxy-5-(hydroxymethyl)-2-methoxy-3-((2-sulfoethyl)amino)cyclohex-2-en-1-ylidene)amino) propanoic acid, a novel MAA called catenelline. 相似文献
6.
Kleber Trabaquini Antnio Roberto Formaggio Lênio Soares Galvo 《Land Degradation \u0026amp; Development》2015,26(4):397-408
Soils from central Brazil have been intensively used over the last decades because of the rapid conversion of savannas ( Cerrado ) into corn/soybean fields. The objective of this work is to study modifications in the physical properties of soils in the Rio Verde watershed, as a function of the land use time for agriculture, determined from classification of Landsat satellite images between 1980 and 2010. Soil samples were collected at surface (0–20 cm) and subsurface (20–40 cm) horizons for the different classes of land use time (<10, 10–20, 20–30, and >30 years). The following physical properties were measured: bulk density (BD), air permeability (Ka), penetration resistance (PR), microporosity (MI), macroporosity (MA), and total porosity (TP). Results showed a strong expansion with time of agriculture that occupied 35·3% (1980), 37·4% (1990), 51·3% (2000), and 60·9% (2010) of the watershed area. When properties were compared with those from the reference areas (preserved soils under native vegetation), significant differences were observed for all the physical attributes of soils for a land use time higher than 20 years. Overall, BD and PR increased with land use time, and the opposite was verified for Ka, MA, and TP. Some physical properties presented values (e.g., 1·54 g cm−3 for BD and 0.06 cm3 cm−3 for MA) close to the critical ones reported to affect crop development, but they were not still impacting on local soybean yield. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Vito Armando Laudicina Agata Novara Vito Barbera Markus Egli Luigi Badalucco 《Land Degradation \u0026amp; Development》2015,26(1):45-53
Several studies have reported how tillage and cropping systems affect quantity, quality, and distribution of soil organic matter (SOM) along the profile. However, the effect of soil management on the chemical structure of SOM and on its hydrophobic and hydrophilic components has been little investigated. In this work, the long‐term (19 years) effects of two cropping systems (wheat monoculture and wheat/faba bean rotation) and three tillage managements (conventional, reduced, and no tillage) on some chemical characteristics of SOM and their relationships with labile carbon (C) pools were evaluated. Soil samples were taken from the topsoil (0–15 cm) of a Chromic Haploxerert (central Sicily, Italy). After 19 years of different tillage and cropping systems management, total organic C significantly differed among treatments with the labile organic C pools showing the greater amount in no till and in wheat/faba bean plots. Hydrophobic and hydrophilic components of SOM, determined by diffuse reflectance infrared Fourier transform spectroscopy, were mainly affected by cropping system, whereas aromatic components of SOM by tillage. Soil organic matter components and characteristics showed significant correlations with the soil biochemical parameters, confirming the expected synergism between chemical and biochemical properties. This study demonstrated that (i) no tillage and crop rotation improve the chemical and biochemical properties of SOM of Vertisols under semiarid environment; and (ii) tillage management and cropping systems have affected, after 19 years, more the chemical and biochemical properties of SOM than its quantity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
文章通过计算各种蛋氨酸源的影子价格并进行比较,探讨其在实际配方中的应用。以现有肉鸡日粮推荐为基础配制了288个试验日粮,DL-methionine为标准添加蛋氨酸,计算蛋氨酸类似物的影子价格。结果表明:液体蛋氨酸羟基类似物(MHA-FA)的影子价格受多种因素的影响,如果想要替代产品具有竞争力的话,应在假定生物学效价计算出的价格上减去大约5.6%。 相似文献
9.
Current silvicultural treatments in beech forests are aimed at achieving thick logs without discoloured hardwood. Therefore
intensive thinning is applied already in younger stands with the objective of large-sized trunks at an age of 100 years. However,
this approach bears the risk that dead wood structures and broken trees are completely removed from the forest. The impact
of three different silvicultural management intensity levels on wood-inhabiting fungi over decades was investigated in a large
beech forest (>10,000 ha) in southern Germany in 69 sampling plots: A Intensive Thinning and Logging with high-value trees,
B Conservation-Oriented Logging with integration of special structures such as dead wood and broken trees and C Strict Forest
Reserves with no logging for 30 years. The analysis of community showed marked differences in the fungus species composition
of the three treatments, independent of stand age. The relative frequencies of species between treatments were statistically
different. Indicator species for naturalness were more abundant at sites with low silvicultural management intensity. Fomes fomentarius, the most common fungus in virgin forests and strict forest reserves, is almost missing in forests with high-management intensity.
The species richness seemed to be lower where intensive thinning was applied (P = 0.051). Species characteristic for coarse woody debris were associated to low management intensity, whereas species with
a significant preference for stumps became more frequent with increasing management intensity. A total amount of dead wood
higher than 60 m3/ha was found to enable significantly higher numbers of species indicators of naturalness (P = 0.013). In conclusion, when applying intensive silvicultural treatment, the role of dead wood needs to be actively considered
in order to maintain the natural biocoenosis of beech forests. 相似文献
10.
Rockfall and snow avalanche events often cause injury to European larch (Larix decidua Mill.) trees, giving rise to the formation of callus tissue and tangential rows of traumatic resin ducts (TRDs). We analyzed and quantified anatomical reactions of juvenile trees injured before the start of the growing season by snow avalanches (15 trees, 324 cross sections) or rockfalls (18 trees, 270 cross sections). Traumatic resin ducts were observed in the growth ring formed following injury in 94.3% of the rockfall samples and 87.3% of the snow avalanche samples. Traumatic resin ducts were formed at the beginning of the new annual ring around wounds caused by rockfalls. In contrast, in trees injured by snow avalanches, TRDs were not formed until after the formation of several rows of early earlywood (EE) tracheids (mean +/- SD = 4.19 +/- 2.56 rows). The dimensions of the EE tracheids observed in the snow avalanche samples were greatly reduced in the tissues bordering the wound, with radial width reaching an average of only 50% and lumen cross-sectional area an average of only 46% of pre-event values. It is therefore possible to differentiate injuries due to past snow avalanches from injuries due to rockfall based on anatomical growth reactions in the tissues bordering scars. 相似文献