Race composition of Blumeria graminis (DC) Speer f. sp. tritici in the south of Ukraine and effectiveness of Pm-genes in 2004–2013

The virulence frequency of 750 wheat powdery mildew isolates of wheat genotypes, carrying 23 Pm-genes and gene combinations, was studied over ten consecutive years from 2004 to 2013. Seventy-eight previously known and 39 new pathotypes were identified during this period. The results indicate that the majority of Pm-genes have high level of virulence. Sixty to ninety percent of the isolates were virulent to Pm6, Pm8, Pm8+11, Pm2+4b+8, Pm3g, Pm10+15, Pm10+14+15. The virulence frequency was variable for Pm1a, Pm2, Pm3a, Pm3b, Pm3c, Pm5, Pm7 genes and reached high level in certain years. The virulence frequency to genes Pm20, Pm37, Pm4a+ and to gene combination with Pm3c+5a+35 and breeding lines CN240/06, CN98/06 and CN158/06 ranged from 1 to 8%. Bread wheat lines CN240/06, CN98/06 and CN158/06, derived from interspecific crosses, proved to be highly resistant to powdery mildew

Application of PCR markers for detecting 1BL.1RS wheat-rye chromosome translocations and (1B)1R substitutions

Aims. Molecular-genetic and cytological analyses were carried out to detect the alien genes in original introgression stocks and to investigate their inheritance. Methods. Rye (Xrems1303, SR1R003) and wheat (Xgwm18-1BS, Xgwm550-1BS, Xgwm140-1BL, Xgwm153-1BL, Xgwm357-1AL, Taglut-1AS) microsatellites and secalin-specific STS-marker (ω-sec-P3+ ω-sec-P4) have been applied. Results. The (1B)1R wheat-rye chromosome substitution and 1BL.1RS translocation have been identified. The pairing between short arms of the 1BL.1RS translocation and of bread wheat chromosome 1B was observed with very low frequency (in 0.3 % PMCs). Conclusions. The stocks have (1B)1R wheat-rye chromosome substitution or 1BL.1RS translocation. The translocation was contributed by the collection strains, derived from wheat cv. Avrora and originated from Petkus rye. The intact rye chromosome 1R for the substitution was contributed by triticale (8x) cv. AD825 and originated from rye Voronezhskaya SHI. The substitution stocks were susceptible to leaf and stem rusts because of another origination of the 1R chromosome. Three major linked genes determining hairiness of the leaf upper surface (Hlup), lower surface (Hllow) and leaf margin (Hlm) were revealed. The genes were contributed by a synthetic (T. timopheevii/Ae. tauschii) and were non-allelic to Hl1 gene. Key words: Triticum aestivum, (1B)1R substitution, 1BL.1RS translocation, hairy leaf, PCR-markers