Abstract:

Many useful genes of wheat-relative species have been transferred to common wheat by chromosome addition, substation and translation and need to be identified. The comparative genomics shows obvious colinearity between wheat and its relative species. A lot of molecular makers have been developed and used to identify alien chromosomes, chromosome segments and genes. Wheat EST sequences are especially valuable as molecular markers because they are derived from gene transcripts and are more likely to be conserved among species. In the present study, in order to develop chromosome-specific markers for chromosome 1R of Secale cereale, 1V of Haynaldia villosa and 1Rk^#1 of Roegneria kamoji, 104 STS primers were designed based on EST sequences downloaded from Graingenes distributed on chromosome 1A, 1B, and 1D of Triticum aestivum using software primer5.0. Out of them, fifty-three pairs of primers amplified polymorphic bands between T. aestivum “Chinese Spring (CS)” and S. cereale, H. villosa, and R. kamoji. Five STS markers, CINAU 19-₅₀₀, CINAU20-₉₅₀, CINAU21-₁₅₀₀, CINAU22-₃₁₀ and CINAU23-₂₀₀₀ amplified specific fragments from S. cereal, T. aestivum-S. cereale amphiploid and 1R addition line, but not from CS and 2R-7R addition lines, were specific to 1R of S. cereale. Five STS markers, CINAU23-₁₇₀₀, CINAU24-₁₀₅₀, CINAU25-₁₆₅₀, CINAU26-₅₀₀ and CINAU27-₆₂₀ were specific to 1V of H. villosa because they amplified corresponding patterns from H. villosa, T. durum-H. villosa amphiploid, and 1V addition, not from CS and 2V-7V addition lines. And five STS markers, CINAU27-₉₆₀, CINAU28-₁₃₆₀, CINAU29-₄₈₀, CINAU30-₅₆₀ and CINAU31-₅₂₀ specific to 1Rk^#1 of R. kamoji were screened by amplifying specific fragments from R. kamoji, Wheat-R. kamoji DA1Rk^#1 and DS1Rk^#1 (1A). Furthermore, markers CINAU27-₉₆₀ and CINAU29-₄₈₀ were located on the short arm, CINAU28-₁₃₆₀ and CINAU31-₅₂₀ on the long arm and CINAU30-₅₆₀ close to the region of centremere of chromosome 1Rk^#1, respectively. This result indicated that STS markers derived from the EST of common wheat are useful for identifying corresponding specific chromosomes of wheat relatives.

Key words: Chromosome specific marker, Expressed sequence tag (EST), Site tagged sequence (STS), Secale cereale, Haynaldia villosa, Roegneria kamoji, Triticum aestivum L.