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Transgressive segregation for rain quality traits in the crossings between covered and hull-less barley Full text
2010
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine the transgressive lines of spring barley (Hordeum vulgare L.) for grain quality traits (1000 kernel weight, and content of crude protein, starch and β-glucans) in the six cross combinations between covered and hull-less barley genotypes. The trial was carried out at the State Stende Cereal Breeding Institute during 2007 and 2008. Lines representing either positive or negative transgression were found in each cross combination if compared covered and hull-less lines with their parent varieties. These lines during the two years of investigation exceeded both parents in positive or negative direction by one standard deviation according to any of the four analyzed grain quality traits. Seven positive transgressive lines were observed regarding 1000 kernel weight, and two transgressive genotypes regarding crude protein content within the population of covered barley lines. No line with positive transgression regarding starch and β-glucan content was found within the covered barley population. 27 hull-less lines showed positive transgression regarding any of the four analyzed grain quality traits. The results show that it is possible to increase grain quality of spring barley grain by implementing selection practices.
Show more [+] Less [-]Characteristic of grain physical traits of spring barley Full text
2009
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objective of this study was to examine the range of variation and correlation relationships of some grain physical traits of different barley types. Field experiments were carried out at the State Stende Cereal Breeding Institute from 2004 to 2006. Grain samples of 52 spring barley (Hordeum vulgare L.) genotypes were analysed for 1000 grain weight, test weight, relative hardness index and hull content. The mean value of 1000 grain weight and test weight for two-row barley was significantly higher than for six-row barley. Test weight for hull-less barley was significantly higher than for covered ones (mean values - 774.6 g lE-1 and 669.8 g lE-1 respectively). The hull content was higher for six-row barley type (10.4%) than for two-row (8.6%) barley. There was no significant difference in relative hardness index between different types of barley. The coefficient of variation for grain hardness ranged from 13.7% for six-row barley to 18.7% for hull-less barley. Among varieties bred in Latvia relative hardness index ranged from 47.1 for two-row variety ‘Sencis’ to 80.4 for only six-row variety ‘Druvis’. Significant (p is less than 0.05) positive correlation was detected between grain hardness index and β-glucans for covered two-row head types of barley (r2-row, covered =0.418 is greater than r25; 0.05=0.396).
Show more [+] Less [-]The evaluation of Rhizobium leguminosarum strains effectiveness in field beans (Vicia faba L.) at different soil microbiological activity Full text
2009
Ansevica, A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Alsina, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Steinberga, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
The inoculation of the legume seed material with active nitrogen fixing bacteria strains before sowing has a significant role for the increase of the legume yield. Inoculation can improve crop yields in cases where appropriate rhizobia are not present in the soil or the soil contains a significant proportion of non-nodulating or ineffective nitrogen-fixing strains. The aim of the investigation was to detect the effectiveness of Rhizobium leguminosarum strains in field beans at different soil microbiological activity. The experiment was conducted at the Institute of Soil and Plant Sciences of the Faculty of Agriculture of the Latvian University of Agriculture from the 5th of June till the 17th of October 2008. The field bean (Vicia faba. L) cultivars - 'Ada', 'Lielplatones', Rhizobium leguminosarum bv. vicia strains No. 110; 408; 501 and 2 types of soils (with different microbiological activity) were used in vegetation pot experiment. The highest shoot dry matter was observed in cultivars cultivated in soil with higher microbiological activity. The highest pod dry matter was observed in cultivars cultivated in soil with higher microbiological activity. The highest total nitrogen amount was in field beans cultivated in soil with lower microbiological activity. Rh. leguminosarum strain resistance to streptomycin decreases with the plants age, from anthesis forward in both soil types and both cultivars. The fingerprinting showed significant difference between Rh. leguminosarum strains.
Show more [+] Less [-]Influence of biological products - Trihodermin and BioMikss on the yield of lettuce and strawberries Full text
2009
Balode, A., Latvia Univ. of Agriculture, Jelgava (Latvia)
Under open environmental conditions, Trihodermin and BioMikss were used for trial purposes to study lettuce (Lactuca sativa L.) and strawberry (Fragaria x ananassa Duch) yields in 2008. Experiments were carried out in the Region of Riga at the farm 'Pukulejas'. The lettuce cultivar 'May King' and the strawberry cultivar 'Senga Sengana' were both used in the trial. The purpose of the trial was to evaluate the use of biological products when applied on the above mentioned trial plants. In the field trial, both Trihodermin and BioMikss in dry powder form in peat mixture were applied for soil treatment 10 kg haE-1. Trihodermin contains cells of microscopic fungus Trichoderma harzianum 8-21 and Trichoderma viride 1-5. BioMikss is a mixture of microorganisms, containing cells of seven various bacteria (Azotobacter chroococcum 23, Polyangium cellulosum 5-t, Polyangium 56, Pseudomonas putida 48-t, Rhizobium meliloti 15, Streptomyces griseoviridis P-t and Streptomyces cellulosae D) and cells of two various fungus (Trichoderma harzianum 7-t and Trichoderma viride A-L). Three times during the growing period Trichodermin and BioMikss water solution 100 g kgE-1 was applied on the trial plants. When compared to non-treated plants, significantly increased yield was observed on BioMikss-treated lettuce. A significantly increased yield was also observed on BioMikss-treated strawberries. The results of the experiments showed that in open environment, both strawberry and lettuce plants treated with BioMikss showed resistance to the grey mould, caused by a parasitic fungus Botrytis cinerea. The results prove that biological products, by environmentally friendly means, revitalize soils, protect plants, and enhance growth, immunity and productive potential.
Show more [+] Less [-]Development of driving cycles for dynamometer control software corresponding to peculiarities of Latvia Full text
2009
Dukulis, I., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pirs, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
Performing biofuel use studies, a large number of parameters that characterize engine operation under different conditions and with different fuel mixtures have to be identified. The real driving conditions are usually simulated by driving cycles on a laboratory chassis dynamometer. There are two major categories of driving cycles: legislative and non-legislative. From the viewpoint of cycle formation there are also two ways. One is composed of various driving modes of constant acceleration, deceleration and speed, and is referred to as modal or polygonal. The other type is derived from actual driving data and is called as 'real world' cycle. There is a strong agreement among researchers that driving characteristics of each city are unique because of different vehicle fleet composition, driving behaviour and road network topography. It is therefore better to develop own driving cycles than using driving cycles developed elsewhere. The aim of this investigation is to develop driving cycles or models for dynamometer control software corresponding to peculiarities of Latvia. The procedure for cycle development and fuel consumption and exhaust emissions measurement was worked out. Using real driving data on the Jelgava streets, models simulating driving in different urban areas were constructed. The model quality was determined using vehicle driving parameters and fuel consumption measurement results from both the road and laboratory tests. Since the obtained data coincidence of all the parameters exceeded 98%, the elaborated cycles can be used for the biofuel use efficiency determination.
Show more [+] Less [-]Chromatographic profiling of hydrophilic metabolites from tubers of different potato cultivars Full text
2009
Zhokhov, S., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Alstroem, S., Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology | Andersson, B., Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Forest Mycology and Pathology | Jastrebova, J., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science
Potato is an important source of nutrients and bioactive compounds with profitable effect for health, such as antioxidants, vitamins and essential amino acids. The knowledge about metabolite composition of various potato cultivars is necessary to facilitate development of new cultivars with desirable properties. In the present study, the hydrophilic metabolite composition of six potato cultivars with different resistance against potato late blight disease was analyzed. For this, an HPLC-based method was developed and used for the analysis of water-ethanol extracts of freeze-dried potato tubers. Significant differences in concentrations of adenosine, chlorogenic acid, and rutin were revealed. Some other metabolites were found to be cultivar-specific.
Show more [+] Less [-]Christmas tree cultivation as an alternative land use - possibilities and profitability Full text
2009
Sirgmets, R., Estonian Univ. of Life Sciences, Tartu (Estonia)
Cultivation of Christmas trees is not a very common activity in Estonia at the moment. There are about 290 000 hectares of former agricultural and pasture lands, which are out of use in Estonia (Aastaraamat Mets 2007, 2008). Taking into account the knowhow from Europe, the hypothetical plantation was established and calculation of profitability was made. Profitability of Christmas tree cultivation was compared to the other alternative possibilities of land use. Achieving the output of saleable Christmas trees at least 50%, cultivation of Christmas trees is very competitive compared to other possibilities of land use, but at same time it is also the most capital-intensive.
Show more [+] Less [-]Bioenergy from pre-commercial thinning, forest infrastructure and undergrowth - resources, productivity and costs Full text
2009
Lazdins, A., Latvian State Forestry Research Inst. Silava, Salaspils (Latvia) | Thor, M., Skogforsk - The Forest Research Institute of Sweden, Uppsala (Sweden)
This article is covering results of pre-commercial thinning, forest infrastructure and undergrowth harvesting field studies implemented in July, 2007 by Skogforsk and LSFRI Silava. A scope of the study was to estimate prime costs of biofuel production from small trees and to compare two types of harvester heads (Bracke C16.a and Ponsse EH25). The productivity in pre-commercial thinning expressed as trees per E0-h (effective hour) ranged between 53 (Ponsse) and 118 (Bracke) in the pine stand and 150 (Bracke) in the mixed spruce stand. In comparison the LVm3 (LV - loose volume) ranged between 9.9 (Ponsse) and 14.1 (Bracke) in the pine stand and was 13.0 (Bracke) in the mixed spruce stand. In the forest infrastructure (roadside ditches) harvesting productivity was 8.2 LVm3 E0-hE-1 for Ponsse and 12.5 LVm3 E0-hE-1 for Bracke. Productivity was economically insufficient in undergrowth removal, both in harvesting (Bracke) and forwarding (Ponsse) operations, respectively 1.1 and 2.6 LVm3 E0-hE-1. Prime costs of harvesting, forwarding, comminution and chip transport (50 km one direction) in pre-commercial thinning in calculation to LVL LVm-3 were 5.93 for Ponsse and 5.85 for Bracke. Prime costs in forest infrastructure in LVL LVmE-3 were 4.97 (Ponsse) and 6.36 (Bracke). Only Bracke was tested in the undergrowth, where prime costs were 37.55 LVL LVm-3. 'Environmental footprint' of biofuel production from small trees in terms of carbon (C) emissions ranged from 2.6 to 10.2 kg CLVmE-3, including road transport (50 km) to terminal.
Show more [+] Less [-]Technical and environmental issues of stump harvesting for biofuel production in Latvia Full text
2009
Lazdins, A., Latvian State Forestry Research Inst. Silava, Salaspils (Latvia) | Hofsten, H. von, Skogforsk - The Forest Research Institute of Sweden, Uppsala (Sweden)
This article represents the results of the research project 'Forest energy from small-dimension stands, infra-structure objects and stumps' realized in cooperation between Joint stock company Latvijas valsts meži (Latvia's state forests), SKOGFORSK (The Forestry Research Institute of Sweden) and Latvian State Forestry Research Institute Silava. The article is covering issues related to the results of stump harvesting field study realized in November, 2008. A scope of the study was to estimate costs of stump harvesting and to evaluate working methods and influencing factors related to extraction of stumps. Better harvesting conditions (flat landscape and lack of stones in soil) led to increased productivity of stump extraction in Latvian trials (5.2 tdry (tdry - tons of dry mass) of stumps per effective hour (E0-h)) in comparison to average figures in Scandinavian studies. Load sizes of the forwarder ranged from 5.5 to 9.3 t which is about half of the maximum load of forwarder. Average productivity of forwarding was 6.3 tdry E0-hE-1. Productivity of stump transport (distance - 7 km) was 3.5 tdry E0-hE-1. Productivity of comminution was 10 tdry E0-hE-1. Prime cost of the stump harvesting, including extraction, forwarding, stump transport (7 km one direction), comminution and chip transport (50 km one direction) was 6.3 LVL LVmE-3 (LV - loose volume). 'Environmental footprint' of the stump harvesting in terms of carbon (C) emissions was 2.5 kg C LVmE-3 of wood chips at terminal. Stumps demonstrated considerably higher heat value (5.7 MWh tdryE-1 against 4.7 MWh tdryE-1 for the hog fuel from a slash).
Show more [+] Less [-]Analysis of entry barriers in highly concentrated sectors of Latvian economy: case of grain processing industry Full text
2009
Jasjko, D., Riga International School of Economics and Business Administration, Riga (Latvia) | Pancenko, E., Riga International School of Economics and Business Administration, Riga (Latvia) | Ivanova, T., Riga International School of Economics and Business Administration, Riga (Latvia)
Encouraging of competitive relations and strengthening of competitive position of domestic producers on both national and EU common market of products and services become one of the main priorities of national economic policy. Latvian national interests are closely related to the maintenance of the competitive environment as an important factor for increase of competitiveness of separate commodity, enterprise or industry, which is able to provide economic growth in the circumstances of declining the business activity and strong competition on internal and external markets. However, fair market competition takes place only on the markets where there are no any essential obstacles and barriers for potential entry of new market actors. That is why the present article is prepared on the basis of case study carried out for Latvian grain processing sector with the purpose to describe and qualitatively assess the effects of various entry barriers, which really exist on the domestic market.
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