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The main objective of this research was to analyze whether selection under conventional conditions (indirect selection) is as effective as selection under organic conditions (direct selection) to develop varieties suitable for organic farming systems. Two F3 barley (Hordeum vulgare L.) populations ‘Primus’/‘Idumeja’ (P/I) and ‘Anni’/‘Dziugiai’ (A/Dz) targeted for organic variety development were selected in two organically and two conventionally managed environments during F3 to F3:6. From there, the performance of the five best F3:6 lines selected in each of the four environments from each cross (in total, 40 lines) were compared at all four sites during two years. For obtaining varieties adapted to organic conditions for the P/I cross, it did not matter at which condition the selection was performed. For A/Dz, the best selection results in terms of yield, combined with other traits included for an organic ideotype, were achieved under well-managed organic conditions. We conclude that direct and indirect selection in early breeding stages are equally suitable for the development of cultivars for organic conditions if (i) care is taken that selection considers not only yield, but also other traits important for organic growing conditions, (ii) selection is not performed under too stressful conditions, and (iii) testing in later stages of the breeding program is conducted under various organic farming conditions for the best recommended varieties for organic agriculture.

Rye (Secale cereale L.) is an important grain crop in Latvia, where it is mainly used for baking rye bread, which is a popular staple. However, the area under rye cultivation in Latvia is small, and the majority of varieties planted are foreign. In 1937, almost 290 000 ha of rye were planted, while in 2011, only 28 000 ha were planted, or ~5% of the area planted with cereals. The Latvian rye genetic resources collection contains nine accessions, including old and new cultivars, landraces and one repatriated accession, which was previously held in the N. I. Vavilov Research Institute of Plant Industry collection. A set of descriptors has been developed for rye, and field evaluations of the Latvian rye collection have been started. A set of simple sequence repeat (SSR) markers has been utilised for genetic fingerprinting of the collection. The initial genetic results indicate that the Latvian rye collection contains a high degree of genetic diversity. Analyses are continuing in order to more fully characterise the collection both phenotypically and genetically.

Diseases of rye (Secale cereale), an important crop in Latvia, might be a risk factor for rye production. The aim of the study was to determine features of rye leaf diseases, to estimate the risk of rye diseases under conditions of Latvia, and to compare various schemes of fungicide treatment that possibly might be useful for integrated disease control. Field trials were carried out from 2009 to 2012 in two locations in Latvia - State Stende Cereals Breeding Institute and State Priekuïi Plant Breeding Institute. Sixteen trials (two cultivars each year, two sites, and four years) were established during the investigations. Each trial was one-factor design with three variants of fungicide treatment: control (without fungicides), standard treatment during heading (GS 51-55), and DSS (Decision support system). Leaf scald caused by Rhynchosporium secalis and brown rust, caused by Puccinia recondita, were found to be the most important rye diseases during the study. Average additional yield achieved by fungicide application was 8%. Number of rainy days (more than seven, starting from GS 31) was not a sufficient threshold for the control of rye diseases. It was necessary to make assessment of the disease development in the the field. Fungicide application might be necessary if symptoms of leaf scald appear on the youngest leaves after beginning of stem elongation (GS 31-32).

Lunasin is a novel, cancer-preventive, anti-inflammatory and cholesterol-reducing peptide that was originally isolated from soy and later from barley, wheat and rye. We report the first discovery of lunasin in triticale (X Triticosecale Wittmack). Moreover, we report first data of lunasin content in winter rye and wheat genotypes grown in Northern Europe. These data are novel as previously published data on finding of lunasin in cereals were obtained in genotypes grown in Korea. Lunasin content was uncovered using a previously published procedure for isolation from cereals and identified by LC-MS/MS assay. We found that triticale was the most lunasin-rich cereal, with the tested genotypes displaying the following trend in lunasin content: genotype 0002-26 > Dinaro > DSGU 10/94 > 0213-22 > 0317-14 > 0006-31. The greatest lunasin content was 6.46 mg/g in the grain of triticale genotype 0002-26. In comparison, the highest lunasin content in rye variety Dankovske Diament was 1.5 mg/g, and the highest lunasin content in the winter wheat variety Fredis was 0.23 mg/g. We conclude that triticale can play a significant role as functional food, with great potential for the use of triticale products in human and animal diets.

Organic agriculture needs spring barley varieties that are adapted to organic growing conditions and have good and stable grain yield across years, even under less favourable growing conditions. The aim of this study was to compare how varieties differ in yield and yield stability under conventional and organic management conditions. The results help to decide under which growing conditions selection of genotypes for organic farming can be most effective. Grain yield and yield components of 10 varieties were estimated in field trials for three years at four sites: two conventionally and two organically managed sites. Varieties differed in stability: some varieties had high yield under conventional conditions and relatively high and stable yield under organic conditions. Heritabilities for yield and yield components were lower under organic (especially in the field with low weed control) than under conventional conditions. Heritabilities for yield components were lower than those for yield itself. Selection for yield components, therefore, may be less effective than selection directly for grain yield. Our data showed that generally the top performing cultivars under conventional conditions also performed as the best under organic conditions, but there were also exceptions. Therefore we conclude that selection of genotypes for organic farming may take place under conventional conditions, but that a final testing should be conducted under organic conditions to confirm the suitability of the selected varieties for cultivation on organic farms.

Association mapping population consisting of 154 Latvian and foreign spring barley genotypes contrasting for traits that are important for organic agriculture was established with the aim to develop molecular markers useful in breeding for organic farming. The mapping population was genotyped at 3072 single-nucleotide polymorphism loci using Illumina GoldenGate platform to provide marker data for association mapping. Field trials in two organically and two conventionally managed locations are being carried out during three seasons. The following traits essential for organic farming were phenotyped: plant morphological traits ensuring competitive ability against weeds, grain yield in organic farming, yield stability/adaptability to organic conditions, nutrient use efficiency (measured as ability to form acceptable grain yield and accumulate protein in grain under conditions of organic farming) and prevalence of diseases. This chapter gives an overview on preliminary phenotyping results. ANOVA showed that genotype and location significantly influenced most of analysed traits (p < 0.01). The average yield reduction in organic trials, when compared to conventional, was 1.2 t ha−1, and it ranged from 4.2 t ha−1 reduction to 1.2 t ha−1 increase. In respect to morphological traits related to competitive ability against weeds (canopy height in beginning of plant elongation, plant ground cover in tillering, length and width of flag leaves, tillering capacity, plant height before harvest), there was a tendency that average trait values were higher in conventional farming locations, but the coefficients of variation were higher in organic locations in most of the cases. The differences in protein content between conventional and organic trials correlated significantly (r = 0.732), and its variation was significantly effected by genotype. The average reduction of protein content in organic fields, if compared to conventional, was 2%, and it ranged 0–6.5%.