Cytogenetic and molecular identification of novel wheat- addition lines with resistance to leaf rust and the presence of leaf pubescence trait.

Introduction: Emerging new races of leaf rust ( Eriks) are threatening global wheat ( L.) production. Identifying additional resistance genes from all available gene pools is crucial to expanding wheat resistance to these virulent leaf rust races.

Impact of Wheat Streak Mosaic Virus on Peroxisome Proliferation, Redox Reactions, and Resistance Responses in Wheat.

Although peroxisomes play an essential role in viral pathogenesis, and viruses are known to change peroxisome morphology, the role of genotype in the peroxisomal response to viruses remains poorly understood. Here, we analyzed the impact of wheat streak mosaic virus (WSMV) on the peroxisome proliferation in the context of pathogen response, redox homeostasis, and yield in two wheat cultivars, Patras and Pamir, in the field trials. We observed greater virus content and yield losses in Pamir than in Patras.

[Mapping a new secalin locus on the rye iRS arm].

A gene designated Sec-N encoding secalin was mapped in the introgressive winter common wheat line Hostianum 273/97 (H273) with the wheat-rye substitution (1B)1R from the octoploid triticale AD825. F2 seeds from crossing the line H273 with the line Hostianum 242/97-2 carrying the wheat-rye 1BL/1RS translocation were analysed. The studied component on the SDS-electrophoregram of total proteins was revealed to be a monomeric secalin which is encoded by the gene at the new locus Sec-N located distally with respect to the Sec-1 locus at a distance of 21.

[Clarification of Rht8 and Ppd-D1 gene linkage on the 2D chromosome of winter bread wheat].

In the south part of Ukraine the haplotype of Rht8c and Ppd-D1a genes is highly distributed among modern bread wheat varieties. During the time of breeding program it has been selected as one of the most important adaptive complex for plants of this region. Genetic distance between Rht8c and Ppd-D1a was clarified.

[Effects of dwarfing genes on the genetic background of wheat varieties of the south Ukraine region].

Effects of the Rht8c, Rht-B1b, Rht-B1e and Rht-D1b genes on the plant height of wheat have been investigated. Variations of these effects are significantly modified by genetic background and year conditions. Complex of the alleles Rht8c Rht-B1a Rht-D1b Ppd-D1a is advantageous for the conditions of the South Ukraine region.

[Identification and characteristics of the 1R (1B) bread wheat substitution strains].

The 1R (1B) chromosome substitution has been identified at two introgression bread wheat stocks derived from the cross between an octoploid triticale and durum wheat. The substitution is marked by original alleles of the secaline coding loci Sec1 and Sec2. At rather low level of chromosome pairing, high winter-hardiness and frost resistance, and yield productivity both in favorable and in unfavorable years the stocks are differentiated for these traits.

[Genetic stability of wheat to fusaria and its connection with trypsin inhibitor activity in seed].

The results of a complex estimation of hybrid lines isolated in F10 from a crossing octoploid triticale and winter hard wheat after a spontaneous hybridization of partially sterile plants with synthetic amphiploid H74/90-245 are presented. It is shown that neither contents of trypsin inhibitor nor resistance to fusarial rots conjugate with resistance to other diseases or to frost. Activity of trypsin inhibitor in grain endosperm allow a decision to be made concerning the presence of alien genetic material in the wheat genome.

[Inheritance of frost resistance and winter hardiness in distant hybrids of wheat and amphiploids].

The data on inheritance of frost resistance and winter hardiness of bread wheat lines obtained as a result of distant hybridization of wheat-rye and wheat-elymus amphiploids with durum and bread wheat were presented. It was shown that selection of the donors of valuable traits is sensible to make in later progenies of hybrids (F6-F7). So, it is possible to obtain the new initial breeding material for winter bread wheat selection with high frost tolerance, winter hardiness and early maturity.

[The effect of alien genomes on the diploidization system in wheat].

Comparative investigation of Elymus sibiricus and other cereal genomes influence on wheat diploidization system was carried out. Elymus sibiricus genome was revealed to have a promoting effect on nonhomologous pairing, however, it is not sufficient for successful introgression of alien genes into wheat. Strain-specific influence of rye genome on nonhomologous chromosome pairing is noted under interaction with ph1b mutation.

[The inheritance of the traits of resistance to fungal diseases by distant hybrids of wheat with amphiploids].

The inheritance of resistance to powdery mildew, leaf rust and septorios of hybrids from crosses of wheat--rye and two wheat--Elymus amphiploids with durum and bread wheat was studied. Spontaneous hybridization was revealed to be a determining factor of the new available trait formation in the wide crosses. Control of the leaf rust and heary leaf traits by the same alien chromosome of Elytricum fertile is confirmed.

[The hybridization of tetraploid wheat with the octoploid wheat-wild rye amphiploid Elytricum fertile and the chromosome behavior in meiotic MI].

The hybridization and chromosome behaviour regularities at meiotic MI of reciprocal F1 hybrids of tetraploid wheats T. durum and T. turgidum with 56-chromosome incomplete wheat-Elymus amphiploid (IWEA) Elytricum fertile, were investigated.