The greatest interest in the cultivation of spring wheat is in regions with an increased intensity of late fallow. However, there are also stronger tendencies to limit the area of its cultivation (similarly to other spring cereals), which is mainly due to a lower level of yielding. Farmers decide on the sowing date of varieties mainly after plants that leave the field late, e.g., potatoes, beets and maize. That is why these varieties are usually called „alternative wheat”. The aim of the research was to determine the effect of autumn sowing date on the yield and the technological value of the grains of selected spring wheat varieties. A two-factor field experiment was established using a split-plot design at the Experimental Station of Cultivar Testing (ESCT) in Bezek (51°12′06″N 23°16′06″E), the Lubelskie Voivodeship, Poland (2008/2009, 2009/2010, 2010/2011). Experimental factors were as follows: A) sowing date – I – October, II – November, III – spring, B) spring wheat variety: ‘Tybalt’, ‘Cytra’, ‘Bombona’, ‘Monsun’, ‘Parabola’. It was found that grain yields of spring wheat sown in the autumn were higher than those sown in the spring term. Without regard to the sowing term, the highest grain yields were obtained from ‘Tybalt’ cultivar.

Yellow rust caused by Puccinia striiformis is a significant wheat disease in cereal growing areas worldwide. On average, yellow rust can cause 50% big yield damages resulting in economic losses. Yellow rust damages wheat leaves, leaf sheaths, awns, and glumes. Puccinia striiformis is divided into four lineages – P. striiformis sensu stricto, P. pseudostriiformis, P. striiformoides, P. gansensis. Different races of yellow rust have been determined. After 2000 three new aggressive races – ‘Warrior’, ‘Kranich’ and ‘Triticale aggressive’ have been identified. New races are characterized by shorter latent period, extended spore germination and tolerance to a high temperature in comparison with the races determined before 2000. These characteristics allowed the new races to replace races dominant before 2000. Yellow rust is a biotrophic heteroecious fungus with a complicated life cycle. For successful development, Puccinia striiformis requires cereals as primary hosts and Berberis spp. as alternate hosts. The history of studies regarding yellow rust is more than two hundred years old but only in 2010 the ecidiospores of yellow rust were found on the alternate host Berberis spp. Two types of resistance – seedling (or all-stage) resistance and adult plant resistance (APR) were discovered. Since 2000 multiple severe epidemics of yellow rust have been observed in cereal growing areas with warmer climate. In recent years, the incidence of yellow rust in Latvia has increased. Particular studies about the biology, distribution, and races of Puccinia striiformis in Latvia are necessary. This article summarizes the information about the classification, biology and harmfulness of the yellow rust.

The aim of the article was to develop formulas, which can be used to model forecasts of production and economic effects of irrigated faba bean (Vicia faba var. minor), depending on drought severity level in a growing season. For the analysis we used data of ten-year (2005 – 2014) production effects of irrigated faba bean and indices calculated on the basis of meteorological data from the measuring point set in the vicinity of the experimental site in region of Bydgoszcz city, central Poland. Based on them, the most relevant relationships between irrigation productivity and chosen drought indices, calculated for a period of high water needs of the plant, were searched. Presented results have demonstrated that the non-irrigated faba bean yields depended significantly on drought severity level and showed very high variability in time. Irrigation contributed to a significant 49% increase in yields and their stability in the years. Due to this treatment, the coefficient of variation of the yield decreased from 55.1 to 19.6%. The production effects of irrigation depended significantly on moisture conditions over the period of high water needs of faba bean. In wet seasons, the increases in yields due to irrigation were insignificant and about three-fold lower, while in the dry periods – more than a half higher (57%) than the average increases. The results presented in the work are of great importance because they can be used to model forecasts of production, as well as to plan the development of irrigation systems in the given area.

Japanese quince (Chaenomeles japonica) is cultivated as a fruit crop because its fruit possesses valuable properties. The total area of Japanese quince in Latvia is continuously increasing; therefore, fruit rot can become an important reason of yield loss. The aim of this study was to clarify the fruit rot incidence in Japanese quince plantations in Latvia and explore the influencing factors of rot development in the year 2017. The evaluation of fruit rot was carried out during the fruit development in eight places of different regions of Latvia where Japanese quince is grown commercially. Three plantations of different Japanese quince cultivars in Dobele and seven plantations where Japanese quince is grown from seedlings were observed. Fruit rot incidence among plantations had no significant differences. Statistically significant differences in fruit rot incidence depending on quince growth stage (p is less than 0.05) were found. Significant differences in fruit rot incidence were found between cultivars in Dobele.

Plant factories provide possibilities to get optimal yield of green leafy vegetables entire year independent from the season. The technology of light-emitting diode (LEDs) light has become one of the most powerful tools in photophysiological researches of various horticultural plants. In order to manage plant physiology and improve productivity, it is necessary to develop new LEDs technologies in horticulture. The aim of the study was to investigate different lighting intensities and elevated red light (660 nm) effect on tatsoi photosynthetic parameters. All plants were grown under the same light sources where overall photosynthetic photon flux density (PPFD) varied from 200 to 300 µmol mE-2 sE-1. Three days before harvesting red light intensity (640 and 660 nm) was increased until 132 µmol mE-2 sE-1 and 660 nm until 188 µmol mE-2 sE-1 at 16 hours photoperiod. In the last treatment merely 24 hours photoperiod was applied. The photosynthetic indices in tatsoi were determined by non-destructive methods using LI-6400XT portable photosynthesis system, OS5p fluorometer, DUALEX optical sensor and CID leaf spectrometer. Research was performed in 2017 – 2018 winter season. The obtained data revealed that the total photosynthetic photon flux density (PPFD) at level of 200 µmol mE-2 sE-1 was sufficient for optimal CO2 assimilation in tatsoi plants. The increased PPFD of LED light at pre-harvest stage resulted in reduced photosynthetic parameters of plants.

The objective of the study was to analyze measurements of the sires used in Latvian Warmblood (LWB) and Latvian Heavy Warmblood (LHWB) breeding programs in the period 2003 – 2017, two major horse populations in Latvia included in one studbook. The Latvian Warmblood has an open studbook for breeding sport horses, whereas the Latvian Heavy Warmblood is a partly closed studbook. Measuring information for all sires with at least one foal born (n=834) in the respective time period was retrieved from the Latvian horse database, with 673 stallions measured at least once. The data consisted of direct measurements – height at withers, chest circumference and cannon bone circumference – and two calculated indices – massivity index and boniness index. Average values of adult stallions were analyzed in four groups – LWB, LHWB, ‘other warmbloods’ and refining breeds, with LWB and ‘other warmbloods’ showing similar average values. Sires were divided by use in breeding into 3-year periods to observe a possible change in the breeding objective and stallion choice, however, no significant differences were found in LWB or LHWB. Average measurements of stallions used in the LWB breeding program (different breeds) were 168.6 ± 4.3 cm for height at withers, 194.4 ± 6.6 cm for chest circumference, 21.8 ± 1.0 cm for cannon bone circumference, massivity index 115.5 ± 3.1, boniness index 13.0 ± 0.5. Average measurements of stallions used in the LHWB breeding program (only LHWB stallions) were 167.6 ± 4.6 cm, 201.4 ± 7.3 cm, 23.7 ± 1.0 cm, respectively, and massivity index 120.0 ± 5.0, boniness index 14.1 ± 0.6. Significant differences between LWB and LHWB stallions were observed in all parameters, except height at withers, and between measurements at the age of 2, 3, 4 years and adult (5 and more years).

Rangifer tarandus (reindeer) – is actively bred in the northern regions of different countries. Therefore, an urgent task is to deepen information about the features of reindeer adaptations. Rumen symbiotic microorganisms play an important role in the life of Rangifer tarandus, allowing animals to efficiently use scarce nutrient resources of the tundra and forest-tundra. The microbial community of the reindeer rumen, as well as its age-related changes, are the least studied compared to other ruminants. The comparative analysis results of rumen bacterial community composition of calf (4 months), young animals (1–2 years) and adults (3–6 years) Rangifer tarandus of the Russian Arctic are presented for the first time. The reindeer ruminal bacterial community composition was analyzed in the laboratory of the ‘BIOTROF+’ Ltd by T-RFLP method. In the ontogenesis, significant changes in the microorganism representation were noticed, the greatest of which was noted in microorganism involved in carbohydrate fermentation. The content of cellulolytic Clostridia and the acid-utilizing species of the Negativicutes (P is less than 0.05) decreased with age, but bacteria with the amylo- and cellulosolytic properties of the phylum Bacteroidetes increased (P is less than 0.05). A wide range of microorganisms which traditionally belong to the pathogens of various animals and humans diseases was revealed. With age, a tendency to increase the number of pathogens, including the bacteria of the families Campylobacteraceae, Burkholderiaceae, phylum Fusobacteria, and the genus Staphylococcus was noticed. The greatest percent of opportunistic microorganisms, including phylum Actinobacteria and the family Enterobacteriaceae, were detected in young animals.

Farming outputs in agriculture depend on the nature of production, i.e. different farming systems generate different outputs. All these outputs are important for the society, and, therefore, require an integrated approach in view of the specific farming characteristics, where market and non-market outputs are taken into account. Therefore, the paper focuses on analysis of farming system outputs and methods of their evaluation. The objectives of this paper are to define the features of different farming systems and their outputs, then, to analyse the methods of evaluation of farming system outputs used in the studies. In order to achieve the research aim, analysis of economic scientific literature has been conducted; characteristics of farming systems and their outputs have been analysed; evaluation methods of the market and non-market farming system outputs, revealing their advantages and disadvantages, have been examined. Methods of systemic and logic analysis have been applied to analysis of the farming system outputs and their evaluation. The analysis has shown that intensive farming systems generate more market goods, while extensive farming systems – more public goods. Price-based methods are mostly used for the evaluation of market outputs of farming systems. Stated preferences methods are the most universal techniques used for the determination of the values from non-market farming system outputs. Hedonic pricing approaches are used for evaluation of specific agricultural public goods related to recreation or leisure and related to the particular groups of users.

Based on data on the number of newly established enterprises and the total number of enterprises, the authors analysed whether and what changes occurred in the industries of the national economy that have high transfer potential in relation to smart specialisation implementation in the country, broken down by region, thereby identifying the RIS3 specialisation field on which the focus has to be placed and to which attention has to be drawn. The aim of the research is to identify the entrepreneurship development in RIS3 specialisation fields broken down by region and economic development according to the RIS3 specialisation fields. The research has found that the number of enterprises in the industries having high transfer potential in relation to RIS3 as a percentage of the total number of enterprises was slightly above 50%; the regional breakdown of the enterprises revealed that two thirds were located in the regions of Riga and Pieriga, and that ICT was the most significant RIS3 specialisation. In the post-crisis period, the number of newly established enterprises increased at the highest rate in 2011, exceeding the rate of the previous year more than two-fold, whereas in the next two years the rate decreased below the 2009 level.

In the fish processing sector, the further exploitation of by-products and wastes left after industrial production promotes sustainability of raw materials, access to added value and increased profitability, as well as contributes to environmental protection by reducing the volume of dumped products. Besides obvious value-added features, it also addresses the clear market demand dictated by prospects of the population growth. Given the limitations for further expansion of the husbandry sector, fish-based items available for human consumption represent a major avenue for coping with the pressing demands of increased population and enable the development of innovative food items of high nutritional importance. Current research is focused on the analysis of fish processing by-product utilization possibilities available up to date and introduces empirical findings of innovative food product development made on the basis of by-products left after traditional canned “Sprats in oil” production. In Latvia, “Sprats in oil” production is an integral part of fish processing sector and the rural economy overall. The production accounts for at least 30% of raw material left as by-products (smoked heads and, in some cases, tails) after such technological stage as smoked sprats processing into cans. Efforts were made to prepare value-added and attractive to customer food product made out of this fish-processing by-products, which are typically processed to a fishmeal or just dumped as waste. The study demonstrates a strong potential for its utilization to a range of fish pâté with various flavours and of high nutritious value.