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Mitochondrial DNA variation of indigenous goat populations from Peste-des-petits-ruminants outbreak in South Kivu, Democratic Republic of the Congo
2018
Bwihangane, B.A. | Gitao, G.C. | Bebora, L.C. | Tarekegn, M.G. | Nicholas, S. | Bacigale, Samy B. | Svitek, Nicholas
This study was conducted to investigate the genetic diversity at d-loop of mitochondrial DNA and establish the possible maternal lineages of indigenous goat breeds in Democratic Republic of Congo (DRCongo). Phylogenetic relationships among and within 111 goats from three indigenous populations from a peste-des-petits ruminants outbreak in South Kivu, Eastern of Democratic Republic of the Congo and 22 goats sequences from the gene bank were analysed using mitochondrial control region sequences (d-loop region). The results show that a total of 120 segregating sites, 56 haplotypes and 124 mutations were found in a 1220-bp sequence. The mean haplotype diversity and nucleotide diversity were 0.971±0.007 and 0.011±0.002, respectively with the overall number of nucleotide differences of 10.73. The phylogenetic analysis showed that all goat sequences were clustered into two haplogroups (A and B), of which haplogroup A was the commonest. The global analysis of molecular variance (AMOVA), incorporating all the three populations independent of any hierarchical clustering, indicated that 83.22% of the total genetic variation present in studied goats was explained by genetic differences between individuals (pv= 0.327), 11.18% among groups (pv=0.000*) and only 5.60% of the variation was attributed to genetic differences between populations (pv=0.003*). These results conclude that there are high levels of intrapopulation diversity in Mwenga-Shabunda, Fizi and Kalehe goats and the weak phylogeographic structuring, thus, suggested that there existed strong gene flow among goat populations probably caused by extensive trans-border movement of goats in the past
显示更多 [+] 显示较少 [-]In vitro methane production and ruminal fermentation parameters of tropical grasses and grass-legume associations commonly used for cattle feeding in the tropics
2022
Uribe, Xiomara Gaviria | Bolívar Vergara, Diana M. | Chirinda, Ngonidzashe | Molina Botero, Isabel Cristina | Mazabel, Johanna | Rosales, Rolando Barahona | Arango, Jacobo
In vitro study was carried out to measure methane (CH4) production and ruminal fermentation parameters of tropical forages either commonly used and with a potential for inclusion in Colombian livestock systems. The forages evaluated wereUrochloa hybrid cv. Cayman, Leucaena leucocephala, Leucaena diversifolia, Megathyrsus maximus cv. Mombaza, Urochloa brizantha cv. Toledo, Canavalia brasiliensis,Urochloa decumbens, Tithonia diversifolia and Dichantium aristatum. which were incubated using the in vitro gas technique for 96 h. Treatments with higher neutral detergent fiber (NDF) and crude protein (PC) contents had higher gas production, dry matter (DM) degradability and the highest CH4 production (ml/g DMd) at 24 hours. Methane at 24 hours of incubation varied between 4.69 and 8.10 ml and increased by 43% on average at 48 hours. In all treatments, the highest proportion of volatile fatty acid (VFAs) corresponded to acetate, which was more than 50% of the total VFAs produced. Treatments with Urochloa hybrid cv. Cayman and their associations with Leucaena diversifolia had the lowest CH4 production values at 24 h. Similarly, treatments with Cayman grass, its associations with Leucaena and Toledo grass alone showed the highest DM degradability values. In conclusion, the inclusion of Leucaena and Tithonia diversifolia on a diet based on forage grass (Cayman or Toledo) had a positive effect on nutrient content and degradability and the group of treatments that included Cayman grass and its associations had lower CH4 production values and higher degradability than the rest of the treatments.
显示更多 [+] 显示较少 [-]The effect of crop rotation and soil tillage on winter wheat yield
2020
Darguza, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Gaile, Z., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Wheat (Triticum) is one of the three most important field crops used for food in the world, as well as in Latvia. The two-factorial trial was conducted at the Research and Study farm ‘Pēterlauki’, Latvia, with the aim to find out the effect of soil tillage and crop rotation on winter wheat grain yield formation. Two soil tillage systems (conventional and reduced), and three crop rotations with different winter wheat (Triticum aestivum) proportion in it (100, 67 and 25%) and different fore-crops (wheat, oilseed rape (Brassica napus ssp. oleifera), faba bean (Vicia faba)) were used. Long-term trial was started in 2009, however, the data from 2016/2017, 2017/2018 and 2018/2019 growing seasons was used for this report. The highest average wheat yield was harvested in 2017 (7.17 t haE−1), and it was significantly (p is less than 0.001) higher than yields in 2018 and 2019 (on average 6.18 t haE−1 and 5.68 t haE−1, respectively). Crop rotation with winter wheat proportion 25%, in which faba bean was wheat fore-crop, showed the highest average grain yield (7.35 t haE−1), but the lowest yield was obtained in rotation with 100% wheat proportion (on average 5.52 t haE−1). Crop rotation scheme had a significant influence on the yield (p is less than 0.001) and 1000 grain weight (p is less than 0.001). Forecrop influenced the yield (p is less than 0.001), number of spikes per 1 square m (p is less than 0.001), and number of grain per spike (p=0.008) significantly. Soil tillage did not affect the studied parameters importantly. Conditions of the trial year affected all parameters significantly.
显示更多 [+] 显示较少 [-]Results of Ribes breeding at the National University of Life and Environmental Sciences of Ukraine
2020
Mezhenskyj, V., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Kondratenko, T., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Mazur, B., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Shevchuk, N., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Andrusyk, Yu., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine) | Kuzminets, O., National Univ. of Life and Environmental Sciences of Ukraine, Kiev (Ukraine)
Breeding work on Ribes species has been started at the National University of Life and Environmental Sciences of Ukraine in Kyiv since 1984 by Petro Sherenhovyj. The breeding programme has been focused on fruit quality, yield, resistance to diseases and pests, as well as on adaptive responses to environmental conditions. As a result of the long-term work, 18 new cultivars were included in the State Register of Plant Varieties of Ukraine in 1999– 2016. The aim of this paper is to describe these varieties: 10 blackcurrant (‘Dochka Vorskly’, ‘Hovtva’, ‘Pam`yati Leonida Mykhalevskoho’, ‘Universytetska’, ‘Aspirantska’, ‘Didorivska’, ‘Poltava 584’, ‘Petrivska’, ‘Yuvileina Sherenhovoho’, and ‘Leleka’), 5 redcurrant (‘Kyianochka’, ‘Poliana Holosiivska’, ‘Buzhanska’, ‘Malva’, and ‘Olha’), 1 whitecurrant (‘Lebidka’), and 2 gooseberry (‘Vasylko’, and ‘Tikych’). The varieties described give farmers and scientists the best knowledge about these cultivars with good level of commercial traits, suitable for dissemination in Ukraine.
显示更多 [+] 显示较少 [-]Influence of drainage reconstruction on radial increment of conifers: case study
2020
Jansone, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia);Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Sisenis, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Pilvere, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Vinters, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Bickovskis, K., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Drainage ensures flow of water and access of oxygen to the roots of the trees. Therefore, melioration systems have been established in a third of the forest area of Latvia, and for the most part highly productive stands can be observed in these areas. Water flow in these systems is often stopped by beaver dams. The aim of our case study was to assess the impact of ditch reconstruction on the increment of the coniferous trees. Increment cores were collected from 169 trees at a distance up to 45 m from the ditch in the drainage system that was reconstructed 8 years prior. Drainage system reconstruction reversed the trend of declining radial increment for both Scots pine and Norway spruce; however, the influence of this measure over an 8 year period was statistically significant, notable (55%) and positive only for Norway spruce, growing closest to the edge of the ditch. Other growth limiting factors need to be considered and tackled to ensure the highest effect of the investment in drainage system reconstruction, including choice of the tree species, stand density, age, and availability of nutrients.
显示更多 [+] 显示较少 [-]Evaluation of compliance of existing forest machine information systems for the implementation of the standard StanForD 2010
2020
Strubergs, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Lazdins, A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Sisenis, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
The aim of the study is to clarify the compliance of machinery information systems used by Latvian logging service providers with the requirements of the Forest Machine Data and Communications Standard StanForD 2010. For determining the number of logging machines and structure registered in Latvia, data from the State Technical Control Agency of Latvia (VTUA) has been used. This dataset includes 2094 registered machinery units from which 1663 units recorded as harvesters and forwarders are distributed for data processing. Using the national AS Latvian State Forests (LSF) database, where 541 machinery units have been recorded, of which 239 harvesters and 302 forwarders, it is determined what and how many machines already use the standard StanForD 2010, how many machines can implement it and which machines are not suitable for the implementation of StanForD 2010. The study showed that the VTUA register does not fully reflect the true quantity of harvesting machines in Latvia and does not provide information about the use of machines. The LSF data provide reliable information on the possibilities of using StanForD 2010 in harvesters in national forests. From the harvesters working in the country’s forests, 52% of the machines use the StanForD 2010 standard. Work should be continued to clarify the possible use of the standard in the machines working in private forests. Similarly, work should be continued with dealers of harvesting machines to identify models for which it is possible to adjust the StanForD 2010 standard and what the cost of adapting the indicative information systems is.
显示更多 [+] 显示较少 [-]Chemical properties of needles as an indicator of nutrient status of fertilized coniferous stands
2020
Karklina, I., Latvian State Forest Research Inst. Silava, Salaspils (Latvia);University of Latvia, Riga (Latvia) | Zvaigzne, Z.A., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Stola, J., Latvian State Forest Research Inst. Silava, Salaspils, Latvia
Enhanced forest growth may respond to demand of woody resources and contribute to the climate change mitigation. Forest soil treatment with fertilizers, as well as drainage and thinning enhance forest growth. The analysis of needles is an established method in forest science to identify the nutrient status in the forest stand and need for forest soil enrichment with fertilizers. The aim of this research is to estimate the efficiency of forest soil enrichment with wood ash and ammonium nitrate in order to eliminate nutrient deficiency in forest stands. Forest soil was enriched with wood ash fertilizer or ammonium nitrate in 2016–2017. The current year needles were collected from fertilized and control plots, from three trees in each plot. The samples were collected in the period 2018–2019. Total nitrogen (g kgE−1), calcium (g kgE−1), magnesium (g kgE−1), and potassium (g kgE−1) were analysed in the collected samples. The chemical properties of collected needles were compared at the individual object level to estimate the impact of fertilizer on forest stand. A statistically significant increase in the concentrations of potassium and phosphorus was detected in some plots treated with wood ash and ammonium nitrate. In addition, a correlation analysis conducted between the variables of chemical properties of needles and soil showed few significant correlations between nutrient content in needles and in soil samples.
显示更多 [+] 显示较少 [-]Composition of extracts isolated from black alder bark by microwave assisted water extraction
2020
Arshanitsa, A., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Ponomarenko, J., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Lauberts, M., Latvian State Inst. of Wood Chemistry, Riga (Latvia) | Jurkjane, V., Latvian State Inst. of Wood Chemistry, Riga (Latvia)
The composition of extracts isolated from black alder bark by ‘green’ microwave assisted water extraction in the temperature range of 70–150 °C was studied using the wet chemistry Folin-Ciocalteu method and Py-GC-MS/FID. The composition data were compared with those of the extracts obtained at the same temperature by accelerated solvent extraction (ASE) of bark. It was shown that microwave assisted extraction, compared with ASE, resulted in more significant transition of major cell wall components, including hemicelluloses and phenolics of lignin origination, into the solution. Depending on the microwave assisted extraction regimes, products with different portion of major cell wall components and secondary phenolic metabolites can be isolated that enlarge the possibilities of products valorisation. Thus, a significant promotion of secondary phenolic metabolites’ transition into extracts as a result of microwave extraction was observed at 70 °C. At that time the relative portion of carbohydrates in extracts was increased at high temperature extraction, combining dynamic and isothermal microwave heating. Water extraction of black alder bark in a microwave extractor revealed 25–50% lower specific energy consumption and 1.8–2.6 times higher productivity in comparison with the conventional extraction, that is beneficial in view of the upscale and practical application of this innovative biomass processing.
显示更多 [+] 显示较少 [-]α-amylase activity in freeze-dried and spray-dried honey
2020
Keke, A., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Honey is a naturally supersaturated sugar solution, which tends to crystallize. The crystallization of honey can lead to unwanted fermentation that can have a negative impact to honey quality. The production of honey powder could be an alternative method to prevent honey from fermentation. Honey powder could be used as alternative substitute to liquid honey that would allow to use this product more widely in the food industry. α-amylase activity is one of the most important parameters to evaluate the quality of honey. The aim of this study was to investigate the effect of freeze-drying and spray-drying on honey α-amylase activity. Detection of α-amylase activity was carried out by spectrophotometric method. High-performance liquid chromatography was used to determine the content of hydroxymethylfurfural in the powders. The obtained results showed that both drying methods had a negative impact to the enzyme activity in the samples. The lowest activity of α-amylase (8.3 DN) was measured in the spray-dried honey powder. Concentration of hydroxymethylfurfural (HMF) in the powders did not exceed required concentration 40 mg kgE−1.
显示更多 [+] 显示较少 [-]Development of ecosystem service opportunities in the Nemunas Delta in the context of global climate change
2020
Pilipavicius, V., Vytautas Magnus Univ., Kaunas (Lithuania) | Zukovskis, J., Klaipeda Univ. (Lithuania)
The second half of the 20th century brought to light the consequences of human activity, when Humanity was confronted with demiurgical complexes and realized that the planet Earth was not only nature, but a complex system that today could no longer be operated by traditional methods and logic. While until the middle of the 20th century man used natural resources only to meet his needs, the 21st century poses new challenges for mankind to manage the consequences of human activities and to use them rationally and sustainably. The paper presents a study aimed at assessing the potential of ecosystem services development in the Nemunas Delta and anticipating their development directions. As a result of the research, the possible development directions of the Elderships were presented. It was done in two scenarios. The research was carried out in six municipality subdivisions (elderships) of the Nemunas Delta area in the framework of the Lithuanian Science Council project ‘Interaction of ecosystem services and human activities in the context of climate change’. Preparation of this paper was supported by funding from European Social Fund (project No 09.3.3-LMT-K-712-01-0178) under the grant agreement with the Research Council of Lithuania (LMTLT).
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