About half of the human population suffers from deficiency of mineral elements, mostly iron (Fe) and zinc (Zn). The purpose of the research was to compare the concentration of Fe and Zn in grain of 19 spring barley (in Hordeum vulgare L.) genotypes and the concentration of Zn and manganese (Mn) in grain of 19 winter wheat (Triticum aestivum L.) genotypes grown in organic and conventional management systems during two growing seasons. The average concentration of Fe in barley ranged from 32.51-86.85 mg·kg-1 and was higher under conventional management (p < 0.001); the effect of genotype was significant (p = 0.014). The average concentration of Zn in barley ranged 16.79-48.51 mg·kg-1 and was significantly higher under the organic system (p < 0.001); in wheat it was 21.52-29.89 mg·kg-1 with no difference between the management systems; the effect of genotype was significant (p = 0.03 and p < 0.001 for barley and wheat, respectively). The average concentration of Mn in wheat ranged from 24.63-36.07 mg·kg-1 and was higher under the conventional system (p < 0.001); significant differences between genotypes were observed (p < 0.001). Barley and wheat genotypes with higher concentrations of the investigated elements were identified for use in breeding for improvement of grain quality. Zn concentration correlated negatively with grain yield and positively with grain protein concentration.
Variation of spring barley agronomic traits significant for adaption to climate change in latvian breeding programmes
Breeding programmes have been recently challenged by climate change. Spring barley (Hordeum vulgare L.) yield, phenological traits (days to heading, length of filling period and days to maturity) and resistance to powdery mildew and net blotch, which are influenced by the rising temperature and precipitation, along with threshability in hulless, were evaluated and their genetic and environmental variability were determined. One hundred and ninety spring barley genotypes were studied, including 129 hulless genotypes and 61 hulled genotypes. The genotypes were grown in the State Stende Cereal Breeding Institute and State Priekuļi Plant Breeding Institute for three seasons during 2007-2009. Broad-sense heritability estimated on the basis of genotypical and phenotypical variances for all traits of hulled barley varied from 31 to 98, and 42 to 98% for hulless barley. For both types of barley the highest heritability was observed for days to heading, filling period and days to maturity. Despite the relatively high estimated heritability for all traits, nevertheless, location, year and interaction of genotype and environment were also been significant for all traits.
Employing cereal genetic variation in breeding programmes for organic farming is one of the ways to create varieties with higher stability and adaptability. The aim of the study was to compare and evaluate grain yield, quality and other traits of barley pure lines, hybrid populations, variety mixtures, as well as winter wheat hybrid populations and parental varieties, in organic and conventional farming systems. Significant evidence for advantages of using barley mixtures and populations under organic and conventional management systems was not observed. More advantages with respect to yield, adaptability to unfavourable environments and TGW were observed for breeding lines selected for suitability to organic conditions. Combination of distinctive genotypes may result in a fairly stable mixture with average yield above the components. The study confirmed that resistance of winter wheat genotypes to abiotic stress is one of the significant traits that is closely connected with limitation of the wheat productivity in both growing conditions. Yield and grain quality value of winter wheat genotypes was lower under organic conditions compared to a conventional growing system. Advantages of populations were not observed under organic conditions, but significantly higher yield, in comparison to parental varieties, was obtained for two populations in conventional conditions. In general, the yield of populations was intermediate to that of the parents.
One of key questions in breeding for organic agriculture is about most appropriate selection environment. A successful man-made cereal species, triticale (Triticosecale Wittm. ex A. Camus.) - is very suitable for growing in organic crop management systems but little research has been conducted on breeding triticale for organic agriculture. Field trials were carried out in Priekuïi during 2009-2012. One hundred F4 winter triticale lines were sown in conventionally and organically managed fields. Selection of the approximately ten best lines in each environment, according to breeders’ opinion with respect to suitability for organic conditions, was made. The selected lines were compared in both organic and conventional fields. The study did not show that there was a need to create varieties for organic farming by selection of triticale in the initial generations in organic fields.
The objectives of the investigation were to identify competitive traits in cereal species in order to contribute to development of a methodology for evaluation of cereal genotypes for their competitive capacity against weeds, which is important for organic breeding aims. The investigation was carried out with spring barley, spring oat, winter triticale and winter wheat genotypes in organic crop rotations in two different locations. Relations between crop traits and weed dry weight were evaluated by Pearson correlation coefficients. The results stressed the significance of some crop traits for cereal competitiveness against weeds for organic breeding purposes: (i) growth habit, canopy height, and crop development rate for spring barley; (ii) crop development rate for spring oats; (iii) winter hardiness and the coefficient of tillering for winter triticale, and (iv) winterhardiness, the coefficient of tillering, the number of productive stems, crop canopy and plant height for winter wheat. It coud be useful to include measurements of crop ground cover for estimating competitiveness of cereal species against weeds