Diversity and evolution of four dispersed repetitive DNA sequences in the genus Secale.

We present the first characterization of 360 sequences in six species of the genus Secale of both cultivated and wild accessions. These include four distinct kinds of dispersed repetitive DNA sequences named pSc20H, pSc119.1, pSaO5(411), and pSaD15(940) belonging to the Revolver family.

Variations of tandem repeat, regulatory element, and promoter regions revealed by wheat-rye amphiploids.

To better understand the evolution of allopolyploids, 4 different combinations between wheat (Triticum aestivum L.) and rye (Secale cereale L.) including 12 F1 hybrids and 12 derived amphiploids were analyzed and compared with their direct parental plants by PCR analysis using 150 wheat SSR (single sequence repeat) markers and by FISH analysis using a rye-specific repetitive sequence (pSc200) as a probe.

[Variation of Rye-Specific repetitive DNA pSc119.1 among sister T1RS.1BL translocations].

Specific primers were designed according to the rye-specific repetitive sequence pSc119.1 and were used for polymerase chain reaction (PCR) analysis using the genomic DNA of two sets of sister T1RS.1BL translocations, CN12, CN17, CN18, 96 I 176-1 and 96 I 176-3 as templates.

[Transfer of a rye small chromosomal segment with powdery mildew-resistant gene(s) into common wheat (Triticum aestivum L.)].

The advanced progeny lines (BC1F5) from the monosomic addition lines between common wheat cultivar Mianyang 11, which is highly susceptible to powdery mildew, and an inbred rye line R12 were analyzed for selection of wheat-rye translocations. Based on a rye-specific repetitive sequence of pSc20H, which spread over all chromosomes of rye but did not existed in wheat, a set of PCR primer was designed and used to identify the rye chromosome segments in wheat. From 300 of the BC1F5 progeny lines 70 were found to contain chromosome composition of rye.

Diagnostic detection and genetic analysis of wheat stripe rust resistant gene YrCN19.

DNA samples of 19 wheat cultivars or lines were screened with the primer pair Xgwm410, a diagnostic marker of wheat stripe rust resistant gene YrCN19. The results showed that the wheat cultivars or lines CN19, XK5, AIM5 and AIM6 produced the amplicon Xgwm410/391, which co-segregated with the resistance of YrCN19, but other cultivars or lines did not produced it. Pedigree analysis and resistance test showed that CN19, XK5, AIM5 and AIM6 carried wheat stripe rust gene YrCN19.

[Molecular cytogenetic identification of a new 1RS/1BL translocation line with secalin absence].

The wheat-rye translocation 1RS/1BL has spread to wheat breeding programs and commercial wheat cultivars throughout the world. But the 1RS arm in the translocation carries locus Sec-1, which encodes rye storage proteins (secalins) and affects bread- making quality. In this study an attempt was made to remedy the quality defect of the 1RS translocation in wheat by developing new 1RS/1BL lines.