Assessing the Genetic Variation of Bulgarian Bread Wheat Varieties by Biochemical and Molecular Markers

The analysis of intra-varietal variation within 5 Bulgarian bread wheats (Triticum aestivum L.), two of which originating from the same cross, was performed using two types of markers: biochemical (seed storage proteins) and molecular (microsatellite) markers.According to the seed storage protein PAGE patterns several biotypes, 4 in each Skitia and Yantar and 2 in each Kristal, Kaloyan and Pryaspa, were selected.DNA fingerprinting profiles of the 14 selected biotypes were obtained using 37 pairs of microsatellite (SSR) primers, amplifying 40 loci. The genetic similarity (GS) among the biotypes within varieties ranged between 0.500 and 0.963 for biochemical markers and between 0.293 and 1.000 for microsatellites.Microsatellite analysis revealed that the varieties Skitia and Kaloyan were the most heterogeneous showing allelic variation in 77.5% and 65% of the studied loci respectively.Usage of the seed storage proteins as markers allowed the differentiation among all of the selected biotypes with exception of Yantar 1 and Pryaspa whereas microsatellite analysis provided no markers for discrimination of Yantar 1 and Yantar 2 biotypes.The high correlation r=0.921 (P< 0.001) between the dendrograms constructed on the base of microsatellite allele data and electrophoretic protein subunit patterns confirmed the usefulness of both biochemical and SSR marker systems for efficient assessment of intra-varietal variation in Bulgarian wheat. The results described here showed that the combined data from both marker types enhanced the discriminatory power of the analyses.