Restriction fragment analysis of the secalin loci of rye.

Analyses of wheat/rye addition lines by Southern blotting confirmed the presence of sequences related to the Sec 1, Sec 2, and Sec 3 loci on chromosomes 1R and 2R. Comparison of the 1R and 2R addition lines allowed the identification of gamma-secalin genes at Sec 1 and Sec 2, respectively, while omega-secalin and gamma-secalin genes at Sec 1 were discriminated by comparative hybridization with three probes: omega-secalin, total gamma-secalin, and 3' gamma-secalin. The high molecular weight (HMW) secalin genes at Sec 3 were identified using a homologous HMW subunit probe from wheat. Gene copy numbers were estimated as about 40-60 for omega-scalins, 5-10 for gamma-secalins, and 2 for HMW secalins. Comparison of individual plants of cv. Gazelle showed a high degree of polymorphism, particularly for sequences related to omega-secalins and HMW secalins.