The research focuses on the study of physically-chemical and microbiological parameter changes in Latvian wild cranberries during convective drying. The research was accomplished on fresh Latvian wild cranberries. The following quality parameters were controlled during the experiments: moisture content (oven-dry method), content of vitamin C (LVS EN 14130:2003), content of polyphenol (HPLC), preparation of samples for microbiological testing (LVS EN ISO 7218:2007), enumeration of yeasts and moulds (ISO 21527-2:2008(E)), counting of lactic acid bacteria (LVS ISO 13721:1995), and total plate count (LVS EN ISO 4833:2003A). The research detected the following optimal convective drying parameters of wild cranberries: temperature – +50±1 deg C and drying time – 20.3 hours. The moisture content of dried berries equalled to 9.0±0.1%. The content of vitamin C decreased 1.9 times in wild cranberries dried at the temperature of +50±1 deg C compared with the content of vitamin C in non-dried cranberries and was 13.05 mg 100 gE-1 in dry matter. The results of current experiments show, that the content of such polyphenols as gallic, caffeic, and epicatechin acids decreased 9.70, 9.90, and 11.68 times, respectively, during the treatment at temperatures up to +50±1 deg C compared with the initial content of these compounds in non-dried berries. The drying temperature substantially influences the microflora development in cranberries. It is possible to decrease significantly the content of LAB, mould, and fungi in berries provided the drying temperature of the wild cranberries does not exceed +50±1 deg C, thus prolonging the ready product shelf-life.

Jerusalem artichoke powder (JAP) from Jerusalem artichoke (Helianthus tuberous L.) roots is a nutritive valuable product that can be used for a healthy product development. The influence of JAP on the quality and degree of liking of cakes was investigated. Sensory evaluation of cakes was realized in two stages: the first - to define the quality attributes of the cakes with JAP from the point of view of the experts, the second – to find out the consumers' views on the cakes, whose quality has been improved in accordance with the recommendations of the experts. As a control sample, the classic home cake was evaluated. Control sample was compared with the cakes, where the amount of wheat flour prescribed by recipe was partly substituted with JAP at different concentrations. Experts evaluated cakes and defined the highest acceptable concentrations of JAP in cakes. For the consumers it was offered to assess the cakes with JAP at concentration 30% and with different taste and aroma enhancers. Cakes with 30% of JAP additive were the most favoured by the sensory properties: aroma, texture, softness elasticity, porosity and softness, surface crust, appearance, colour, shape, and size. Results of analysis of variance showed that there no significant differences in the degree of liking between the cakes with JAP and the cakes with taste and aroma enhancer additives (p is greater than 0.05). There had been performed hardness analysis and colour measurement for cakes with JAP. The observed results declare high influence of aroma and taste enhancer on cakes structure and colour.

Both the rowanberries (Sorbus) and the chokeberries (Aronia) belong to the family Rosaceae. The berries of these cultivars are suitable for production of health-food products. The main components in the dry matter of fruits are carbohydrates, primarily sugars. The aim of this experiment was to determine the content of simple sugars and sorbitol in different fresh rowanberry cultivars and chokeberries and to compare the composition of these compounds after freezing and thawing of berries. The experiments were done in the Customs laboratory of the National Customs Board, State Revenue Service (Latvia). The rowanberries were picked in the Pure Horticultural Research centre, and black chokeberries were obtained from farm 'Ceplīši' (rural municipality of Pure). The contents of dry matter and soluble solids were analyzed in fresh berries, and the contents of sugars and sorbitol were analyzed both in fresh berries and in berries after freezing and thawing of 13 different cultivars of rowanberries and one black chokeberry. For determination of the soluble solids content, the refractometric method was used, and for determination of the glucose, fructose, sucrose and sorbitol content, high performance liquid chromatography was used. The results showed that rowanberries and chokeberries contained 3.24-7.24 g 100 gE-1 of sorbitol which was the dominant compound in all investigated berries. The highest content of sorbitol was found in the wild rowanberries and rowanberries Sorbus aucuparia var. sibirica, but fruits of rowanberry×pear 'Alaya Krupnaya' contained the least content of sorbitol. After freezing and thawing of berries, the content of sugars and sorbitol were decreased by 5-23% with some exclusion.

Appropriate discount rate for forestry is still an issue for the forest economy. Therefore, it is significant to understand the importance of discounting, and how costs of forestry production process are valued. Forest regeneration and new stands tending costs are considered as investments; they are related to each particular stand. For that reason, the goal of this study was to compare how the value of this investment is growing at the bank deposit or 1 ha forest stand. The study examined the growth rate of two different tree species value with young forest stand establishment and tending investments depositing in the bank or the growth rate of compound interests. As discounting formula derived from a compounding formula, it would allow to find an appropriate discount rate for each timber species. High rates of compound interest cause a very rapid and unrealistic future value increase, while low rates cause slow value increase for a very long period represented by a common forest rotation; for that reason high discount rates used in forestry are not rational. Taking into account an income from intermediate cuttings, the value of timber species in comparison with the deposit significantly improves. Suitable discount rate determination in forest assessment is mainly determined by the species of wood productivity and cutting age. As it is hard to find two identical forest properties, each situation should be considered individually, taking into account and understanding the relationship between a growth rate of timber and compound interests, thus choosing an appropriate discount rate.

One of the key factors affecting the formation of high-quality forest is thinning. Latvia's yearly budget of commercial thinning is not met; therefore, there are plenty of forests which are not thinned as planned and this leads to declining quality of forest stands. The timber processing industry needs significant excluded volume of timber, but forest owners are unable to maximize profits in future. Extensive logging of commercial thinning is hindered by economic factors and forestry regulations. Logging business is not satisfied with the productivity indicates and restricting forestry and environmental laws. The world's leading forest engineering firm offers a variety of forest harvester design and structural solutions. The first real use of commercial harvesters in commercial thinning in Latvia's conditions revealed several problems. The most important one is how to increase harvester productivity, while ensuring the quality of residual stands. To increase effectiveness of the logging machines and the proportion of commercial thinning, it is necessary to explore main factors affecting harvester productivity. This work aims to clarify the main pressures hampering harvester productivity and evaluate the quality of remaining trees in commercial thinning in Latvia. The main results are that during night productivity of harvester decreases by 12%, while marking trees to be cut down with fluorescent colour increases productivity of harvester at night by 15%. Productivity of harvester in thinning depends on average volume of harvested trees. These results of the work were obtained through various experiments on twelve different commercial thinning areas in Latvia.

Large proportion of 30-50 years old spruce stands originated from overstocked plantations can be characterized by low growth potential and present serious problem to forest managers. Although according to legislation unproductive spruce stands can now be clearcut, possible alternative solution allowing a forest owner to remove only trees with the worst growth potential would be also welcome. To be able to recommend any silvicultural measures, information on the inner structural development of the stands is necessary. The aim of this study was to analyze temporal structure of several spruce stands that have originated from overstocked plantations and now belong to the 2nd (increased risk stands) or 3rd (unpromising stands) growth potential groups. Data for the study from seven sample plots located in Forest Research Station ''Kalsnava'' and thinned with different intensity were used. Tree diameter distribution, volume accumulation patterns and tree mortality were analyzed. Correlation between tree diameter and tree diameter difference in the observation period from 2000 to 2006 was weaker than in the observation period from 2006 to 2009, indicating further decline of growth potential. In most cases the major part of the volume was accumulated in the middle of the diameter class distribution. For most of the trees one or both sawlogs were of good or average quality. In order to develop optimal and profitable stand management model, the effect of different thinning methods in spruce stands of low growth potential should be studied in the future.

Black alder wood is suitable for production of high quality veneer and other uses, but doe to its small share in total forest area (3%) in Latvia its genetic improvement have not been a priority. Set of progeny tests, together 22.8 ha, have been established only in the last decade. First of them have reached the age of 8 to 10 years and are suitable for first assessment. Aim of our study was to evaluate potential of improvement of black alder using selection, based on progeny testing. Data from 4 open pollinated progeny tests of phenotypically selected black alder plus trees, located in central part of Latvia, each containing from 15 to 21 families, are evaluated, using breeding value as a criterion. Results reveal that selection of parent trees with the practically possible intensity (10%) yields notable improvement in height at the age of 8 to 10 years: from 10 to 32%. Parent trees of open-pollinated families S9, S14, S16 and 84115 that have superior productivity and above-average quality can be recommended for establishment of second-round seed orchard. Estimates of genetic parameter suggest that selection in black alder trials could be carried out with high accuracy and improvements are possible both in productivity and quality (branch thickness, stem straightness, occurrence of spike knots).

This study was undertaken to assess the potential for sweet potato silage making business by estimating sweet potato vines and root wastage and assessing the economic feasibility of investing in sweet potato silage. Information was collected through key informant interviews, secondary data review, sweet potato root peeling and weighing, focus group discussions with pig and sweet potato producers covering a sample of 180 farmers. Semi-structured interviews with 240 respondents (120 sweet potato farmers, 60 pig farmers and 60 sweet potato traders) were also conducted. The results showed that sweet potato production is seasonal with substantial wastage of sweet potato components existing across the various nodes of the sweet potato value chain. The study concludes that there is an opportunity for investment in sweet potato silage business that has the potential to reduce wastage of sweet potato and bridge the feed scarcity gap faced by pig farmers.

The aim of the work is to investigate raw milk from different bulls' daughters to clear up the influence of cows' genetic predisposition to milk microbial contamination and somatic cell count (SCC). Particular attention is paid to develop productive cow milk yield, milk fat, milk protein and in recent years, the SCC heredity. The literature describes a variety of lines and families, representatives of the resistance to certain diseases (leucosis, mastitis, tuberculosis, brucellosis, foot disease), it shows the determination of a genetic factor for this trait. If the selection results show increased resistance to a disease, then this indicates a genetic disease resistance and shy. The paper focuses on microbial contamination of raw milk at 7 different studies of bull daughters in the same line for housing, feeding and conditions of use. Raw milk samples were obtained from the breed Latvian brown (LB) from dairy cows shed of cattle shed Saujas, which belongs to SIA Palsa and is located in the civil parish Varini, Smiltene county in the year 2008/2009. Compared between the lines of bulls' daughter milk yield of the sample average value of the uniformity of variance analysis shows that they significantly differ (F=2.452, p=0.039). Comparing each line of bulls' daughters SCC of the sample average value of the uniformity of variance analysis showed that the SCC was statistically significantly different (F=2.083, p=0.075) of the various lines of bulls daughters.

Latvia is a territorially small country with small open economy, and its main and the most competitive recourses are highly educated society and well developed science which is based on research, innovation and modern technologies. To create a well functioning innovation system as a part of knowledge-based economy, several conditions has to be met to insure that all parts of national innovation system effectively work together. This article is dedicated to analysis of financing mechanisms that can be used by research institutes in the field of agriculture in Latvia to ensure sustainable rural development. The research in the field of agriculture in Latvia is mainly performed by the state research institutes and research agencies of Latvia University of Agriculture. To provide favourable environment for development of research and science, there is set legislation framework and financing mechanisms such as base financing from the state budget, state research programmes, European Commission Framework Programmes, and the European Union (EU) Structural Funds assistance. The analysis has shown that support of EU Structural funds has positive impact on number of applied research carried out in research institutes in the field of agriculture in Latvia. EU Structural funds assistance helps to develop fundamental research activities and innovative approach to the science that is one of the preconditions for the development of states' competitiveness. In conclusion, the authors resume that it is necessary to establish a strong link between higher education institutions, research institutes, and entrepreneurs in the process of building effectively working national innovation system.