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Development of effective extension methods to motivate farmers for the adoption of improved water management practices
1985
Ali, A. | Saleem, M.
To study and improve existing watercourse layout system for its maximum efficiency
1985
Khan, M.H. | Ali, M.B.
Reproductive performance indicators of dairy cattle in selected small-scale dairy farms in semi-arid Eastern Kenya Full text
2019
Mungube, E.O. | Njarui, D.M.G. | Maichomo, M.W. | Olum, M.O. | Ndirangu, P.N. | Kabirizi, J. | Ndikumana, J. | Mwangi, G.
Mitochondrial DNA variation of indigenous goat populations from Peste-des-petits-ruminants outbreak in South Kivu, Democratic Republic of the Congo Full text
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
Show more [+] Less [-]The effect of crop rotation and soil tillage on winter wheat yield Full text
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.
Show more [+] Less [-]Results of Ribes breeding at the National University of Life and Environmental Sciences of Ukraine Full text
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.
Show more [+] Less [-]Occurrence of genetic lineages of Puccinia striiformis in Latvia Full text
2020
Feodorova-Fedotova, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia). Inst. of Soil and Plant Sciences;Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia). Research Inst. of Plant Protection | Bankina, B., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia). Inst. of Soil and Plant Sciences
Puccinia striiformis is a biotrophic pathogen able to cause broad scale epidemics in wheat growing regions. P. striiformis is genetically highly variable pathogen. New, aggressive genetic lineages, adapted to warm temperatures have been observed in the last decades worldwide. The study aimed to ascertain the structure of genetic lineages of P. striiformis in Latvia. Forty one wheat leaf samples with yellow rust symptoms were collected in 2017–2019. Fenotyping and genotyping methods were used for identification of genetic lineages in Global Rust Reference Center, Denmark. Assessments of leaf diseases on winter wheat differentials – ‘Ambition’, ‘Mariboss’, ‘Moro’, ‘Compair’, ‘Rendezvous’, ‘Spalding Prolific’ and local variety ’Fredis’ were made during the research. Five genetic lineages of P. striiformis – PstS4, PstS7, PstS10, PstS13 and PstS14 were found. 56% from the samples belonged to PstS14, 17.1% PstS10, 12.2% PstS4 and PstS7, 2.4% PstS13. Genetic lineages identified from Latvian wheat samples are found in the biggest cereal growing regions in Europe and are able to cause epidemics on wheat. Genetic lineages of P. striiformis from Latvian samples have not been identified before. All differential varieties were infected with P. striiformis in 2017, ‘Ambition’ and ‘Moro’ in 2018, no infection was observed on differentials in 2019 despite the presence of P. striiformis on winter wheat variety ‘Fredis’. The identification of genetic lineages of P. striiformis on wheat in Latvia is necessary to continue.
Show more [+] Less [-]Comparision of regeneration of Scots pine \{Pinus sylvestris L.\} in Myrtillosa and Hylocomiosa forest types after shelterwood cuttings Full text
2020
Rums, O., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Straupe, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Zdors, L., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The aim of the study is to determine how successful the initial growth of naturally grown and planted pines is after performing the shelterwood cutting. The research includes tree count and height analysis in Myrtillosa and Hylocomiosa forest types with different regeneration methods in 2018. A total of 10 sites were arranged for the research, each site having 4 sample plots. All naturally regenerated and planted pine (2009, 2012 and 2013) heights were measured. Judging by the number of trees after shelterwood cutting, most sites should not be considered regenerated, additional planting or scarification of soil is required which can improve the efficiency of natural regeneration. In all the sites both in Myrtillosa and Hylocomiosa, after shelterwood cutting it was observed that the height of artificially regenerated trees is higher than the height of naturally regenerated trees, indicating the ability of planted pines to produce more rapid height increment in the first years of life, regardless of forest type. The basal area of the stand has a significant negative impact on the increment, and it indicates the need for the subsequent shelterwood cut to be performed. Although Hylocomiosa is a more fertile forest type than Myrtillosa, the height of the planted pine trees in Myrtillosa is higher than in Hylocomiosa, where, after shelterwood cutting, no sufficiently intensive agro-technical tending has been performed.
Show more [+] Less [-]Smartphone-based colorimetric determination of DPPH free radical scavenging activity in vegetable oils Full text
2020
Vucane, S., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Sabovics, M., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Leitans, L., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia) | Cinkmanis, I., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
Free radicals can rapidly and irreversibly oxidize various structures, including unsaturated fatty acids in vegetable oils, which affect the sensory properties. Spectrophotometry is the most widely used method for the determination of free radical scavenging activity (RSA) using 2,2-diphenyl-1-picrylhydrazyl (DPPH). Barrier to the further use of classical analytical methods to analyse biologically active compounds in foodstuffs is that equipment requires high cost and has limited mobility. One of solutions is to replace classical methods, such as spectroscopy, with smartphonebased colorimetry. Huawei P30 Lite smartphone was used for colorimetric detection. The free radical scavenging activity (RSA) in vegetable oil was detected using an application ‘Color Picker’, with image matching algorithm for red, green, and blue (RGB) model. RSA was expressed as percentage and measured by the DPPH method. The aim of the study was to determinate the total free radical scavenging activity with smartphone-based colorimetry. For the data comparison and accuracy spectrophotometer as analytical optical instrument was used. Eleven vegetable oils: sea buckthorn, sunflower, rice, macadamia nut, hemp, corn, grape, linseed, rapeseed, olive and milk thistle oils were selected for analysis. The best results with no significant differences (p is greater than 0.05) compared to smartphone-based colorimetry from spectrophotometry were determined using RG values. The poor results were detected by using B value (p is less than 0.05) and were not suitable for determination of RSA. Smartphone-based colorimetry can be used in the determination of the RSA in vegetable oils.
Show more [+] Less [-]α-amylase activity in freeze-dried and spray-dried honey Full text
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.
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