Grain quality adversely affects price and consumer acceptance of finished products. Hagberg falling number (hereinafter falling number) is one of the most important grain quality indices of winter wheat (Triticum aestivum L.), especially in humid climate countries (Northern Europe). Field experiments with winter wheat cultivars ‘Bussard’ and ‘Zentos’ were conducted at the Latvia University of Agriculture, Study and Research farm ‘Peterlauki’ during a three year period (from 2009/2010 to 2011/2012). The aim of this investigation was to clarify variation of the falling number (FN) depending on cultivar, weather conditions and different rates of nitrogen (N) fertilizer applied (N 60, N 90, N 120, N 150) on fresh and stored grain (60, 120 and 360 days). During the investigation period, wheat ‘Zentos’ grain was characterised by a higher falling number compared with ‘Bussard’ grain. The falling number values for fresh grain for both wheat varieties studied were high: averagely 301 s for ‘Bussard’ and 359 s for ‘Zentos’, and reached demands set for grain suitable for bread baking. Differences in the falling number values were noted when freshly harvested winter wheat grain was compared with grain stored for 60 or 120 days and 360 days. During storage (60 – 360 days), α-amylase activity in winter wheat grain reduced and the FN increased on average up from 94 to 110 s. The falling number significantly depended on weather conditions, grain storage period and nitrogen fertilizer. The higher was the falling number of freshly harvested grain, the higher its increase during grain storage of compared to freshly harvested grain with a lower falling number value.

Pisum sativum L. (field or garden pea), is widely cultivated in Europe. The purpose of this investigation was to see whether pea varieties differ in their yield and content of protein and nutrients. Another aim was to select the best varieties suitable for breeding or production. A field experiment with different varieties of peas (‘Bruno’, ‘Capella’, ‘Clara’, ‘Mehis’ and ‘Vitra’) was carried out at the Estonian Crop Research Institute in 2014. Yields (t haE-1) were not statistically different. Crude protein content (g kgE-1 in dry matter) was lowest in ‘Clara’; all other varieties had a higher content of protein, within much the same range. The lowest N content was found in ‘Clara’, followed by ‘Capella’ and ‘Vitra‘, ‘Mehis’ (44) and the highest in ‘Bruno’ (45). The lowest P content was found in ‘Clara’, followed by ‘Capella‘ and ‘Vitra’; the highest was found in ‘Bruno’ and ‘Mehis’. The lowest K content was found in ‘Mehis’, then ‘Clara’, followed by ‘Capella’ and ‘Vitra’ and the highest in ‘Bruno’. The lowest Ca content was found in ‘Clara’, followed by ‘Capella’ and ‘Mehis’, ‘Vitra’, and highest in ‘Bruno’. The lowest Mg content was found in ‘Capella’, followed by ‘Clara’ and the highest in the other varieties ‘Bruno’, ‘Mehis’ and ‘Vitra’. Thus, choice of the right variety for pea cultivation is very important, but depends on the local agro-climatic conditions. This investigation has been developed with the help of the project EUROLEGUME, funded from the European Union Seventh Framework Programme for Research, Technological Development and Demonstration under the grant agreement no. 613781.

In Estonia, the most promising perennial grass used as raw material for production of heat energy is reed canarygrass (Phalaris arundinacea L.). Nordic countries (Finland, Sweden) implement a technology including single harvest of the above-ground biomass from frozen soil early in spring. This technology cannot be used in Estonia as the ground does not freeze to the extent of bearing harvesting machines every year. Harvesting in spring is virtually impossible as herbage lodges excessively under the snow weight. A divided harvesting method of reed canarygrass was tested in field trials in 2010–2013 at the Estonian Crop Research Institute. Herbages were cut in July at the height of 60–65 cm, mass was dried as hay, stubble hay was left to grow and was harvested next spring before the growth started but soil had become dry. The effect of seeding rate, row spacing and nitrogen fertilizer on the dry matter yield of reed canarygrass was investigated. The amount of produced heat by trial variants was calculated. The variant with narrow spacing (15 cm), seeding rate of 8 kg haE-1 and usage of fertilizer N70 in the beginning of growth and N70 kg haE-1 after the first cut was giving the best results. Two cuts of this variant yielded on average 8.12 t haE-1 per year, of which the stubble hay, harvested in spring and with better combustion properties, made 64%. Energetic value of the yield was 138 GJ haE-1 per year.

The objective of this study was to evaluate the main plant nutrient: mineral nitrogen (NH4 + -N and NO3 -N) dynamic in soil under fertilizing for obtaining high grain yields of winter wheat (Triticum aestivum L.) and to determine relationships between nutrient uptake and winter wheat productivity. The field study was carried out at the Research and Study farm ‘Vecauce’ of the Latvia University of Agriculture for two years 2012/2013 and 2013/2014 with winter wheat variety ‘Kranich’. Different nitrogen application rates (0, 85, 153, 150, 175, 180 and 187 kg haE-1) and timing were used for winter wheat. The content of nitrates NO3 -N and ammonium nitrogen NH4 -N was determined in the soil layers 0-0.20 m, 0.20-0.40 m, 0.40-0.60 m. Nitrogen management strategy during the plant growth period based on soil Nmin evaluating can improve N use efficiency and reduce environmental contamination. The maximum of mineral nitrogen content in soil in the vegetation period was observed at the beginning of stem elongation with a tendency to decrease. A significant impact (p is less than 0.05) of nitrogen fertilizer application was noted on the mineral nitrogen content in soil layer 0-0.20 m deep in both trial years. The increasing doses of nitrogen fertilizer raised the amount of mineral N in the soil profile. The significant impact (p is less than 0.001) of nitrogen application and year conditions was observed on grain yield. Close positive correlation significant at 99% probability level was observed between the grain protein content and nitrogen concentration mostly in all soil layers, but it was not found between the grain yield and nitrogen content.

Environmental conditions and climate change on a global scale affect the overall agriculture and food supply. Globe artichoke (Cynara cardunculus var. scolymus (L.) Fiori) is widely distributed all over the world. Immature inflorescence, commonly called capitula or head, is used in human consumption. These vegetables are a good source of human health promoting components. Artichokes are widely used in human diet, characterized by low protein and fat, high content of minerals, vitamins, inulin, carbohydrates and polyphenolic compounds. Relationship between plant growth and development is tight and complicated. Many agroecological factors, such as temperature, irrigation and fertilization level, planting and harvesting date, influence processes of growing and development of globe artichoke. Biologically active compounds in plants are dependent on climate conditions, seasonal changes, cultivar properties and maturity. Pre-germination is required for better plant establishment in the field. Better plant growing and development can be ensured by regular irrigation which provides 85 – 100% from evaporation and applied fertilization before planting and during vegetation period according to soil properties. The biochemical quality of artichoke heads differs between cultivars, head fraction, and stage of head development. This indicates possibility to grow artichokes in Latvia.

Oat (Avena sativa L.) is one of the small grain crops produced in temperate climate zone. Common oat has been studied most often due to its multifunctional characteristics and nutritional profile. The main function of the oat husk is to protect grain from harmful conditions during harvesting and storage time. Oat grain size uniformity is an important parameter to the oat milling industry. The aim of this study was to compare the husk content of common oat cultivars grown in Latvia and to obtain its changes at different grain size fractions during three growing seasons. The field trial was carried out at the State Stende Cereal Breeding Institute from 2012 to 2014. Ten husked oat genotypes were studied. Oat samples were fractioned into size fractions and samples of each fraction dehulled by hand. Results showed that significant (p is less than 0.05) differences in the husk content were observed among genotypes, growing season and different grain size fractions. Significantly lower husk content was for genotype ‘Arta’ in all growing seasons. For majority of used genotypes increasing grain size the husk content decreased.

Legumes (Leguminosae) are one of the most widely grown crops in the world after cereals (Poaceae). They are not only an important source of protein in food and feed, but also a significant component of different agrosystems. The N2 fixation by legumes is of great importance in nutrient management and sustainable economy of nitrogen. Legume productivity largely depends on a successful formation of symbiosis between the plant and soil microorganisms. The most important among those are rhizobia and mycorrhiza fungi. The field experiment was carried out at the Institute of Soil and Plant Sciences, Latvia University of Agriculture in 2014 to evaluate the influence of double inoculation using rhizobium leguminosarum and mycorrhiza fungi preparation on yield formation of broad bean V. faba L. var. major Harz ‘Bartek’. The bean seeds were treated with rhizobia and/or mycorrhiza fungi before sowing. Seeds were treated with rhizobia by soaking in bacteria suspension for 30 minutes directly before sowing. Mycorrhiza fungi preparation was added in soil under seeds before sowing. Plant height, fresh and dry weight and the weight of nodules were measured at the beginning of broad bean flowering (BBCH 60-61). rhizobium leguminosarum response to double inoculation differed between the strains. Rhizobium leguminosarum strain RL407, isolated from Vicia faba, was shown to be the most appropriate strain used for inoculation of broad bean seeds. Bean seed double inoculation increases the protein content significantly comparing to single inoculation using mycorrhiza fungi preparation.

Heat is one of the most important types of energy at northern latitudes. In 2013 the total consumption of renewable energy resources (RER) in Latvia was 68 PJ. The heating systems can function on plant or other organic material, for example, wood chips or agricultural residues. By using local biomass resources it is possible to reduce the pollution of atmosphere caused by greenhouse gas emissions. Different variety of winter wheat (Triticum aestivum), triticale (Triticosecale) and rye (Secale cereale) were used in the research. The following aspects were determined during the research: dry matter yield, chemical composition and the higher heating value of grains and straw. The evaluation of grains and straw of winter cereals showed that the higher heating value (MJ kgE-1) was acquired from the straw of winter cereals, whereas the grains had the highest dry matter yield, thus the grains of winter cereals had the highest heating yield from one hectare (GJ haE-1).

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.

This study was carried out in 2012 to determine the effects of different irrigation intervals and irrigation water amounts on the cut flower performance of oriental lilium (Lilium L.) ‘Casa Blanca’ cultivated in greenhouse conditions. Different ratios of the plant water consumption (Tr) calculated using exterior radiation values of the greenhouse were applied to the plants as irrigation water. Irrigation water amounts varied between 199.3-589.0 mm, whereas measured plant water consumption (ETa) varied between 314.9-613.8 mm according to the treatments. Different irrigation water amounts and irrigation intervals had statistically significant effects on flower stem length, flower stem diameter, stem weight and number of flowers. In the study the stem length varied between 26.4-74.7 cm, stem weight varied between 72-175 g, stem diameter varied between 5.0-9.5 mm and the number of flowers buds varied between 3.6 and 8.0. The experimental treatment on which about 1.25 times of the potential plant water consumption calculated in two day intervals and the experimental treatment on which about 1.50 times of the potential plant water consumption calculated in four day intervals were selected as irrigation program.