Polymorphism of Glu-1 locus in hexaploid triticale germplasm resources

Hexaploid triticale (a new species) was artificially synthesized by crossing tetraploid wheat with rye. Its processing quality was related to its HMW-GS composition. To provide reference for the processing and utilization of hexaploid triticale germplasm resources, HMW-GS composition at Glu-1 locus was investigated in 101 samples from Xinjiang and 11 accessions from Poland using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Results showed that 3 1(a), 2*(b), Null(c) ; 8 7(a), 7+8(b), 7+9(c), 6+8(d), 20(e), 13+19(g), 7+18(r), 6.8+20y(s) and 6 1^r+4^r(a), 2^r+6.5^r(b), 6^r+13^r(c), 2^r+9^r(d), 6.5^r(e), 0.8^r+6^r(f) alleles were encoded by Glu-A1, Glu-B1 and Glu-R1, respectively. This indicated that alleles at Glu-R1 were the richest. Null(c) at Glu-A1, 7+18(r) at Glu-B1 and 6^r+13^r(c) at Glu-R1 were found to be the main subunits, occupying 58.93%, 67.90% and 58.00%, respectively. Other subunits such as 1(a) at Glu-A1; 7(a), 6+8(d), 13+19(g) and 6.8+20y(s) at Glu-B1; and 1^r+4^r(a) and 0.8^r+6^r(f) at Glu-R1 were only detected in a few varieties. 30 HMW glutein patterns were found in 121 accessions of Null, 7+18, 6^r+13^r (c, r, c) and 2*. Also only 7+18, 6^r+13^r (b, r, c) were the main accessions, occupying 16.91% and 16.02%, respectively. Some distinctive glutein patterns such as 2*, 7+18, 2^r+9^r(b, r, d) and 2*, 6.8+20y, 2^r+6.5^r(b, s, b) were detected. Genetic variations index at Glu-1 locus of triticales from Xinjiang and Poland were in the order of Glu-R1 > Glu-A1 > Glu-B1 and Glu-R1 > Glu-B1 > Glu-A1, respectively. This indicated that genetic variation at Glu-R1 locus was richer than those at Glu-A1 and Glu-B1 in all detected materials. Analysis of genetic polymorphism revealed that genetic variation in the Poland accessions was richer than that in the Xinjiang accessions. Moreover, 7+18(r) and 6.8+20y(s) at Glu-B1 were new and special subunits formed during artificial evolution of triticale. It provided rich gene resources for improving wheat processing qualities.