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.

The objectives of the investigation were to determine effect of hull-less gene on grain quality traits (crude protein, starch and β-glucans) and to evaluate the heritability of these traits in the F4 and F5 generations of six crosses between covered and hull-less barley (Hordeum vulgare L.). The trial was carried out at the State Stende Cereal Breeding Institute during the years 2007 and 2008. Mean value, range and the coefficient of variation of traits for covered and hull-less lines within each cross combination were calculated. Heritability of quality traits was estimated as intergeneration correlation (r) and linear regression coefficients (b). The highest intergeneration correlation values were observed for starch content within covered and hull-less barley populations (rF4:F5=0.609 and 0.635 respectively). Moderate intergeneration relationship was observed for crude protein content within covered barley population (r=0.582), and for β-glucans content within hull-less barley population (r=0.593). The regression estimates of heritability were higher for starch content for both covered and hull-less barleys (b=0.549 and 0.703 respectively). Due to effects of genotype and environment interactions the regression estimates of heritability for crude protein and β-glucans content for both covered and hull-less barley were low (b varied from 0.347 to 0.373).

The experiment was carried out in the Latvia University of Agriculture. The objectives of this research were to study changes of bean (Phaseolus) protein fractions occurring under the thermal treatment conditions and determine the critical temperature for Maillard reactions in beans. In these reactions lignified protein is made from amino acids and sugars, and it decreases the nutrition value of the food. If lignified protein exceeds 50% of crude protein content in food, then food is considered unsuitable for daily diet. In this experiment beans were milled and then heated at 50 ± 3 °C, 75 ± 3 °C, 100 ± 3 °C, 125 ± 3 °C and 150 ± 3 °C temperature in the drying oven for 20 h. As a control sample non heated beans were used, and they all were kept in a plastic jar at room temperature (20 ± 1 °C). Dry matter, crude protein, starch, sugar and lignified protein content were determined in heated beans and control samples. No significant changes of crude protein content were observed due to thermal treatment. It was from 24.3 ± 0.3 g 100 g-1 of dry matter. Similarly, no significant changes were observed in starch content, as it stayed averagely 47.1 ± 0.2 g 100 g-1 of dry matter. Medium high correlation was observed (0.64) between lignified protein content and sugar content for in different temperature treated beans. Lignified protein showed exponential growth if the samples were heated at a temperature of 100 ± 3 °C and higher, giving exponential change.

Renewable energy resources play an important role in energy production both in Latvia and in the world. Bio-ethanol is used as a substitute for oil products in various countries of the world. It is produced from the plants containing starch: cereals, potatoes, beet, maize. The task of the research was to evaluate the suitability of different varieties of winter wheat, triticale and rye for extraction of bio-ethanol in Latvia. The research was carried out at the State Stende Cereals Breeding Institute in 2009, and the following varieties and lines of cereals were examined: winter wheat varieties 'Mulan', 'Skalmeje', and the line '99-115', developed at the State Stende Cereals Breeding Institute; winter triticale varieties 'SW Valentino', 'Dinaro', and the line '0002-26', developed at the State Priekuli Plant Breeding Institute; winter rye varieties 'Matador', 'Placido' Fp and 'Dankowskie Nowe'. The content of crude protein and starch of grains, the grain yield, and the bio-ethanol yield were determined. The highest bio-ethanol yield was acquired from the winter wheat and triticale varieties that had the highest starch content and the lowest crude protein content of grains. The best results were obtained from winter wheat line '99-115' and variety 'Mulan' (409.4 and 406.8 L tE-1), triticale variety 'Dinaro' (423.3 L tE-1), and winter rye variety 'Matador' (370.1 L tE-1.).

Field trials were carried out at Jõgeva Plant Breeding Institute in 2008 – 2011 to identify the possibilities of using early red clover (Trifolium pratense L.) ‘Jõgeva 433’ (diploid), Washington lupine (Lupinus polyphyllus Lind.) ‘Lupi’ and crimson clover (Trifolium incarnatum L.) as green manure. Fresh material of the above species was ploughed into the soil in autumn of the sowing year. Fertilizer value was quantified through yield and grain quality of spring wheat ‘Vinjett’ and barley ‘Inari’. The composition and amount of ploughed biomass were recorded. By the time of ploughing, Washington lupine had produced the most abundant biomass. >From studied species crimson clover had the lowest fertilizer value – only by 6–7% extra yield of spring wheat in the following year. Crimson clover had no residual effect of fertilization in the second year. The fertilizer values of red clover and Washington lupine were approximately equal. Their effect on yield increase of spring wheat and barley lasted for three years, on grain quality for two years. Red clover, ploughed into the soil in the year of sowing, resulted in maximum spring wheat yield increase of 23.9%, compared with N 0 treatments; that of Washington lupine was 21.3%. The residual positive effect in the second year quantified as barley production increased by 6.2% in Washington lupine and 7.9% in red clover. The yield increase in the third year was 3.9% and 12.1%, respectively. Green manure increased the contents of crude protein and gluten in spring wheat and crude protein content in barley.

The aim of the work was to study accessions of Dactylis glomerata L. of different origin for breeding in the Leningrad region. The work was carried out at the Leningrad Agricultural Research Institute. The study involved 15 accessions. The nursery was founded in 2016 and included two replications for green yield and two – for seed production. Cutting and sampling for biochemical studies were conducted in May-June 2018, seeds were collected in July. The amount of ascorbic acid, carotenoids and chlorophylls and crude protein were determined. Statistical analysis included the calculation of the parameters of variation, ANOVA and correlation analysis. Three groups were identified by the degree of ripeness: a small group of early maturing – 31 days, a group of late maturing (single accession from Karelia) – 51 days, a large group of middle maturing – 34–37 days. For the late maturing accession the mechanism of regulation of the beginning of heading is due to the sensitivity to photoperiod. The adaptive potential of widely zoned varieties is wider than for localized. Their productivity is higher. The content of pigments in the green mass is closely correlated. The system of pigments in the complex of characters is separate, but is positively associated with the seed productivity and negatively – with the content of ascorbic acid. The seed productivity of the accessions is related to the total pigment content and power of the generative shoots (length and mass).

The objective of the study was to examine the range of variation in chemical composition of different barley types. Field experiments were carried out at the State Stende Cereal Breeding Institute from 2004 to 2006. Grain samples of 52spring barley (Hordeum vulgare L.) genotypes, including two-row, six-row, covered and hull-less genotypes were analysed for starch, crude protein, crude fat, crude fibre, crude ash and phosphorus. On the average, the six-row barley genotypes had a significantly larger content of crude protein (152.0 g kgE-1), crude fibre (53.5 g kgE-1), crude ash (24.4 g kgE-1) and phosphorus (4.7 g kgE-1) but less starch (590.4 g kgE-1) than the two-row barley genotypes (626 g kgE-1). The hull-less barley grain contained significantly more crude protein (149.4 g kgE-1), crude fat (25.4 g kgE-1) and phosphorus (4.7 g kgE-1) than covered ones. The largest coefficient of variation was found for crude protein of covered barley (15.0%), for crude fibre of hull-less barley (13.8%) and for phosphorus of six-row barley (18.0%) genotypes. Consequently, energetic value was slightly higher in the hull-less barley with waxy type of endosperm, because of the higher fat (27.1-28.3 g kgE-1) and starch content (622.3-680.7 g kgE-1) and less crude fibre (17.3-17.4 g kgE-1) and crude ash (18.9-21.2 g kgE-1) content.

This research was conducted to determine the chemical composition of smooth bromegrass in artificial pasture from the years 2010 to 2012 in Isparta Province located in the Mediterranean region of Turkey. The mixture of the pasture used were alfalfa (Medicago sativa L.) + sainfoin (Onobrychis sativa Lam.) + crested wheatgrass (Agropyron cristatum L.) + smooth bromegrass (Bromus inermis L.). Animal grazing applications were performed in the second and the third year of the study since the first year covered only the establishment of the artificial pastures. Forage samples were collected from grazing and non-grazing areas once every 15 days during the grazing seasons. The crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF) contents, total digestible nutrient (TDN) and relative feed value (RFV) were determined on the smooth bromegrass forage samples. According to results, CP, TDN and RFV values decreased throughout the grazing season, while ADF and NDF contents increased in grazing and non-grazing areas. The ADF and NDF contents of smooth bromegrass in non-grazed areas were higher than the grazed areas, while CP, TDN and RFV values of grazed areas were higher than non-grazed areas. It can be concluded that the harvesting at the late stages caused a reduction in forage quality of smooth bromegrass in grazing and non-grazing areas.

The purpose of research was to analyze dairy cows (Bos taurus) milk productivity according to the calving body condition score (BCS) and to predict the nitrogen output with urine according to BCS and live weight. The research was carried out at the Research and Study farm ‘Vecauce’ of Latvia University of Agriculture. Data were collected from 55 dairy cows during October 2013 to October 2014. Dairy cows were from different breeds (Holstein Black and White, red breed cows with Holstein blood more than 40% and crossbreeds) and different lactations. Cows were grouped in two groups for the estimation of BCS effect on the analyzed traits: BCS is less than or equal to 2.5 and BCS is greater than or equal to 2.6. BCS was estimated at calving and in monthly recording control days. Nadir value of BCS is greater than or equal to 2.6 group was 2.64 ± 0.06 points on the third control day, but 2.46 ± 0.08 points of BCS is less than or equal to 2.5 on the second control day. Calving live weight of BCS is less than or equal to 2.5 and BCS is greater than or equal to 2.6 groups were 613.8 ± 13.3 kg and 651.1 ± 11.4 kg. The highest milk yield was observed in BCS is greater than or equal to 2.6 group until the third control day, the highest fat content was observed in this group, but the highest protein content was in BCS is less than or equal to 2.5 group. Milk urea content was not significantly affected by calving BCS, but milk urea content of BCS is greater than or equal to 2.5 group ranged from 23.2 ± 1.86 to 30.9 ± 1.98 mg dLE-1, and from 20.6 ± 1.53 to 30.2 ± 2.27 mg dLE-1 in BCS is greater than or equal to 2.6 group. A significantly higher urinary nitrogen output was observed from BCS is greater than or equal to 2.6 group on the second control day – 237.8 ± 8.1 g dayE-1 (p is less than 0.05).

In plot trials, seeded in a pure stand without a cover crop, tetraploid red clover varieties bred at Jogeva - 'Varte' (early) and 'Ilte' (late), outyielded the diploid standard varieties in crude protein yield at optimal harvest schedule by 30.8% as an average of two production years (the yields 2255 and 1724 kg ha*[-1), respectively) and 14.9% (the yields 2073 and 1804 kg ha*[-1), respectively), by 26.3% as an average of three production years (the yields 2254 and 1785 kg ha*[-1), respectively) and 28.4% (the yields 2173 and 1693 kg ha*[-1), respectively). Considering the crude protein content of dry matter and crude protein yield, a three-cut harvesting regime should be applied in early tetraploid red clover varieties to attain the best result. Then the first cut should be taken at the budding stage, the second at early bloom of regrowth and the third cut prior to the commencement of night frosts. The late tetraploid red clover varieties should be harvested twice-the first cut at the budding stage and the second cut prior to the first night frosts. The larger crude protein yield of tetraploid varieties was caused mainly by their higher dry matter yield; it was affected to a lesser extent by the crude protein content of dry matter. Yet, the tetraploid varieties exceeded in majority of harvest times the diploid varieties in dry matter's crude protein content but the excess was mainly insignificant.