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Wheat-rye T1BL.1RS translocation is widespread worldwide as the genes on 1RS arm have positive effect on stress resistance, grain yield and adaptation ability of wheat. Nowadays, the T1BL.1RS wheat cultivars have become susceptible to rust diseases because of the monophyletic (‘Petkus’) origin of 1RS. Here we report and discuss the production and detailed investigation of a new T1BL.1RS translocation line carrying 1RS with widened genetic base originating from Secale cereanum. Line ‘179’ exhibited improved spike morphology traits, resistance against stripe rust and leaf rust, as well as higher tillering capacity, fertility and dietary fiber (arabynoxylan) content than the parental wheat genotype. Comparative analyses based on molecular cytogenetic methods and molecular (SSR and DArTseq) makers indicate that the 1RS arm of line ‘179’ is a recombinant of S. cereale and S. strictum homologues, and approximately 16% of its loci were different from that of ‘Petkus’ origin. 162 (69.5%) 1RS-specific markers were associated with genes, including 10 markers with putative disease resistance functions and LRR domains found on the subtelomeric or pericentromeric regions of 1RS. Line ‘179’ will facilitate the map-based cloning of the resistance genes, and it can contribute to healthy eating and a more cost-efficient wheat production.

High-molecular-weight glutenin subunit (HMW GS) proteins are major components of the gluten matrix, which is the physical basis of bread-making in wheat. Epigenetic and transcriptional regulations of HMW GS genes were studied both in silico and in wet lab to understand their tissue (endosperm) specific expression. Our co-expressional network analysis identified key transcription factor (TF) genes that regulate HMW GS genes. We also show here that HMW GS genes are inhibited in vegetative tissues by histone deacetylation as revealed by strong GUS expression in vascular tissues of transgenic barley seedlings harbouring HMW GS gene promoter::uidA-reporter gene fusions upon treatment with a histone deacetylase inhibitor. A novel method termed in vivo DNA affinity purification (IP) has been developed here for the isolation of histones and transcription factors binding to target DNA regions. The technique is based on the biolistic introduction of biotinylated PCR probes amplified from HMW GS gene promoters into wheat leaves. Twenty-four hours later, the probe is cross-linked with interacting factors and subsequently re-purified from plant nuclear extracts. Many proteins, ribosomal proteins and histones have so far been isolated. No lysine-acetylated histone protein fragments were found which further highlight the inhibiting effect of histone deacetylation on HMW GS gene expression.

Understanding the genetic diversity of Aegilops biuncialis, a valuable source of agronomical useful genes, may significantly facilitate the introgression breeding of wheat. The genetic diversity and population structure of 86 Ae. biuncialis genotypes were investigated by 32700 DArT markers with the simultaneous application of three statistical methods— neighbor-joining clustering, Principal Coordinate Analysis, and the Bayesian approach to classification. The collection of Ae. biuncialis accessions was divided into five groups that correlated well with their eco-geographic habitat: A (North Africa), B (mainly from Balkans), C (Kosovo and Near East), D (Turkey, Crimea, and Peloponnese), and E (Azerbaijan and the Levant region). The diversity between the Ae. biuncialis accessions for a phenological trait (heading time), which is of decisive importance in the adaptation of plants to different eco-geographical environments, was studied over 3 years. A comparison of the intraspecific variation in the heading time trait by means of analysis of variance and principal component analysis revealed four phenotypic categories showing association with the genetic structure and geographic distribution, except for minor differences. The detailed exploration of genetic and phenologic divergence provides an insight into the adaptation capacity of Ae. biuncialis, identifying promising genotypes that could be utilized for wheat improvement.