Introgressions of Vitis rotundifolia Michx. to obtain grapevine genotypes with complex resistance to biotic and abiotic stresses.

Vitis rotundifolia Michx. is one of the species of the family Vitaceae, with resistance to both biotic and abiotic stresses. The present study reports new scientif ic knowledge about the inheritance of resistance to downy mildew, powdery mildew and frost by V. vinifera varieties from V. rotundifolia. Recombinant lines of three hybrid populations from the crossing of the maternal genotype ♀M. 31-77-10 with V. rotundifolia hybrids were used as the object of the study. As a result of laboratory screening, more than 40 % of recombinants of the ♀M. 31-77-10 × × [DRX-M5-734 + DRX-M5-753 + DRX-M5-790] population showed a high degree of frost resistance (-24 °C), while 6 % of transgressive recombinants were characterized by a very high degree of resistance (-27 °Ð¡). The maternal genotype ♀M. 31-77-10 does not carry alleles of resistance to powdery mildew at the Run1 locus and in the f ield suffers from powdery mildew much more than the paternal genotypes. The prevalence of powdery mildew on vegetative organs in the three recombinant populations over the years varies on average between 3.2-17.1, 0.3-17.7 and 0.6-5.2 %, respectively. As a result, almost all recombinant genotypes that received a resistant allele from the paternal genome are highly resistant to powdery mildew.

[Natural nucleotide polymorphism of the Srlk gene that determines salt stress tolerance in alfalfa (Medicago sativa L)].

Based on legume genome syntheny, the nucleotide sequence of Srlk gene, key role of which in response to salt stress was demonstrated for the model species Medicago truncatula, was identified in the major forage and siderate crop alfalfa (Medicago sativa). In twelve alfalfa samples originating from regions with contrasting growing conditions, 19 SNPs were revealed in the Srlk gene. For two nonsynonymous SNPs, molecular markers were designed that could be further used to analyze the association between Srlk gene nucleotide polymorphism and the variability in salt stress tolerance among alfalfa cultivars.

[Detection of genetic determinants that define the difference of near-isogenic Triticum aestivum L. Lines in photoperiodic sensitivity].

Identification of genetic determinants that define different degrees of line sensitivity to the photoperiod was conducted on material of near-isogenic lines of the soft hexaploid wheat Triticum aestivum L. using SSR markers and markers specific to the Vrn and Ppd genes. It was established that the Ppd-s line contains a dominant Ppd-Dla allele located on chromosome 2D. This allele is characterized by a vast deletion in the gene promoter region. For two other lines (Ppd-m and Ppd-w), introgression of the Ppd-B1 gene on chromosome 2B was shown from the parental Sonora variety, which is slightly sensitive to the length of the day; however, the previously described Ppd-Bla. 1 allele was not found. Another polymorphism that can cause weak photoperiodic sensitivity, an increased amount of the Ppd-B1 gene copies, was detected for these lines.

[The transcriptome analysis of barley (Hordeum vulgare L.) using the Affymetrix Barley1 GeneChip].

An alternative to complete genome sequencing is development and analysis of ESTs-fragments of transcribed coding DNA sequences. The EST collections also enhanced the development of cDNA microarray technologies, which make possible assessing the transcription levels of several thousand genes in a studied tissue of an organism in the same experiment. This paper provides an overview of the results of experiments with a barley microarray, Affymetrix Barley1 GeneChip. The variation in transcription levels of over 22000 genes in germinating barley grain of 150 barley double haploid lines produced by crossing cultivars Steptoe and Morex. Variation in gene expression of each gene is a quantitative trait, which can be mapped in population of double haploids as the genetic loci determining its variation (expressed QTL or eQTL). A regulatory locus (eQTL) can colocalize with the corresponding gene on genetic map (cis-eQTL) or be distant from it, frequently on another chromosome (trans-eQTL). Thus, it is possible to detect and analyze cis- and trans-regulatory loci for genes on a genome-wide scale. The design of the Affymetrix oligonucleotide arrays makes it possible not only to concurrently test the transcription level of several thousand genes, but also to simultaneously detect the polymorphic regions in cDNA sequences, thereby finding a considerable fraction of all nucleotide substitutions between the compared genotypes. Two types of data (the expression levels of several thousand genes and the presence of polymorphic sites in their sequences) can be obtained concurrently when processing the results of the same experiment. The details of both procedures are illustrated with explanatory examples.

[Genetic singularity coefficients of common vetch Vicia sativa L. accessions determined with molecular markers].

Organization and practical application of ex situ collections require estimation of genetic differences between numerous accessions of local cultivars and field weed forms collected from the same ecological and geographical region and similar in their morphophysiological characteristics. A mathematical algorithm for estimating the degree of genetic singularity of a specimen in the system of local gene pool determined with the help of molecular markers is described. The utility of this algorithm is demonstrated by the example of classification of 677 common vetch accessions from the collection of the Vavilov Institute of Plant Industry from 11 ecological-geographic regions of Russia analyzed using AFLP. The proposed classification of accessions is the result of processing the AFLP data by weighting the marker traits based on their frequency in particular regions. This allowed each accession to be characterized according to the ratio of rare and frequent alleles as a genetic singularity coefficient. The proposed method is appropriate for any types of molecular markers. A practical result of its application is the classification of accessions using a five-point score scale, which can be added to descriptors of certificate databases and used for optimization of the work with collections.