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Māra Bleidere, Ieva Mežaka, Linda Legzdiņa, Ilze Grunte, Indra Beinaroviča and Nils Rostoks

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.

Open access

Nadezhda Zoteyeva, Ilze Skrabule, Ieva Mežaka, Daiga Vilcāne, Guna Usele and Nils Rostoks

Abstract

Potato breeding clones were evaluated for resistance to late blight (agent Phytophthora infestans) using tuber inoculation tests and for presence of the resistance alleles of R1 and R3a genes in polymerase chain reaction tests. Among clones tested those expressing high, moderate and low resistance were identified. The data were analysed for the impact of R1 and R3a genes on tuber resistance to late blight in tested plant material. In previous evaluations performed on smaller amount of clones the tuber resistance levels significantly depended on presence/absence of the resistance allele of R3a gene and did not depend on presence of R1 gene allele. In the current study the statistical analyses did not prove the significant difference in resistance levels depending on presence of the resistance alleles, neither of R1 gene, nor of R3a gene. Tuber resistant clones bearing R3a gene resistance alleles still noticeably prevailed over the clones bearing the alleles of R1 gene as well as over the clones bearing the no resistance alleles of both genes. In several cases the resistance of clones with detected resistance allele of R1 gene was higher compared to those derived from the same crosses and showing amplification of the allele of R3a gene or those with no resistance alleles. Clones accumulating the resistance alleles of both (R1 and R3a) genes expressed high tuber resistance accompanied by necrotic reaction.