Vernalization requirement in hexaploid wheat is largely controlled by a series of homoeologous VERNALIZATION (Vrn) genes, Vrn-A1, Vrn-B1, and Vrn-D1. The sequence of the promoter area and first intron of Vrn-D1 were analysed in 77 hexaploid accessions, representing five wheat species (Triticum compactum, Triticum sphaerococcum, Triticum spelta, Triticum vavilovii, and Triticum macha) sampled from different ecogeographic areas within 35 countries. Polymorphism was detected in the Vrn-D1 promoter, resulting in a new Vrn-D1 haplotype (named here, Hap-8T). Analysis of Vrn-D1 intron-1 sequences revealed a novel insertional mutation in a subset of T. spelta and T. compactum accessions. This mutant allele was designated Vrn-D1s. Analysis of the 844 bp insertion revealed it to be a nov el tra nspo sab le DNA e l emen t (nam ed DTA_Chimera_KF800714) not previously described in Triticum, belonging to the hAT superfamily. Finally, we describe a PCR-based assay that discriminates the wild-type vrn-D1 allele from the Vrn-D1s allele. Collectively, the work described here highlights the potential of utilizing minor hexaploid wheat species for the identification of novel alleles of agronomic importance.

Genetic organization of 52 Vibrio cholerae El Tor biotype preseventh and seventh pandemic strains isolated in various periods was studied by PCR assay and DNA-DNA hybridization. It was established that the genome of most ancient of analyzed strains isolated from a diarrhea patient in 1910 was devoid of CTX and RS1 prophages, vibrio pathogenicity islands (VPI and VPI-2), and pandemic islands (VSP-1 and VSP-2) that contain key virulence genes. The appearance of pathogenic properties in cholera vibrios for the first time causing a local outbreak of cholera in 1937 is connected with the acquisition of VPI and CTX that carried genes tcpA and ctxAB, respectively, which are responsible for the colonization of the small intestine and encode the production of cholera toxin. The appearance of the seventh pandemic agent for cholera was shown to correlate with the acquisition by its precursor of two additional blocks of genes VSP-1 and VSP-2. This finding strongly supports the involvement of these genes in formation of the pandemic potential in the strains. Molecular typing methods allowed elucidation of differences in the genetic organization between prepandemic and pandemic strains. The detected variability of the genome of contemporary virulent strains may be a reason for the occurrence of etiological agent of cholera with new properties.

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Analysis of microsatellite sequences was used for estimation of genetic diversity of cultivated and wild sunflower and usefulness for genotype identification, genetic purity and "hybridity range" definition. In total 13 SSRs were tested. Unique alleles for some wild sunflower species were found. Eight out of 13 SSR loci were polymorphic for the investigated inbred lines. Four of the investigated microsatellites are suitable and sufficient for genome identification and determination of parentage of hybrids. A procedure is proposed for sunflower genotype registration based on DNA-typing.

Common bunt, caused by Tilletia caries (DC.) Tul., is widespread disease of wheat (Triticum aestivum L.) that causes serious yield reduction and loss of quality of this crop. Majority of Ukrainian wheat varieties are susceptible to bunt. It is necessary to search for sources of effective resistance genes.Aegilops cylindrica (2n = 28; genome CCDD) is a source of genes for some pest resistance in wheat Bochev et al. (1982). Ae. cylindrica carries resistance to leaf rust, stem rust, fusarium, septoria, powdery mildew and common bunt.The identification of DNA-markers linked to bunt resistance and susceptibility alleles would greatly facilitate the screening of wheat introgressive genotypes and accelerate the development of new resistant varieties. Microsatellites or simple sequence repeat (SSR) is widely used to search for molecular markers linked to many economic traits genes McIntosh et al. (2003).Present study reports markering and mapping with microsatellite markers of effective resistance gene to bunt in bread wheat introgressed from Ae. cylindrica. Bunt evaluation. Ae. cylindrica, recurrent parent wheat cv. Odesskaya polucarlikovaya and line Lutestens 23397, introgressive lines 5/55-91, 378/2000 and BC 3 F 2 -derived F 3 families were evaluated for resistance to bunt in field infection nursery. Bunt resistance in line 5/55-91 is controlled by a single dominant gene (Babayants et al. 2004). MATERIALS AND METHODS PlantMicrosatellite marker analysis. For SSR-analysis were used 95 pair primers to 107 microsatellite loci with known localization on chromosomes of wheat (Röder et al. 1998). For identification microsatellite markers linked to the resistance gene was used bulked segregation analysis (BSA) as described by Michelmore et al. (1991