Assessment of Genetic Diversity in Croatian Winter Wheat Varieties Using Ssr and Aflp Markers

Genetic diversity relies on very complex statistical approach that involves variance among alleles at single gene loci, among several loci, between individuals within population and among populations (Smale, 1997). Nevertheless genetic base of crop plants population is also associated with responses to selection pressures. So plant breeding is based on detection and application of genetic variation. Analysis of genetic diversity among elite germplasms can offer predictive estimates of genetic variability between segregating progeny for pure line cultivar development (Manjarrez-Sandoval et al., 1997). There are several methods to estimate genetic diversity: morphological, agronomical, economical, pedigree, biochemical and molecular. The use of molecular markers is now broadly used in breeding programs because of their subjectivity exclusion. In many studies combination of several diversity criteria for more accurate estimation is used (Solemani et al., 2002; Marić et al., 2004; Stodart et al., 2005). In bread wheat two marker systems were extensively used in recent years for mapping and diversity estimates, the microsatellites or simple sequence repeat (SSR) and amplified fragment length polymorphisms (AFLPs). Microsatellites are ubiquitous in plants (Powell et al., 1996), and have very high level of polymorphism and ability to distinguish close related genotypes (Morgante and Olivieri, 1993; Plaschke et al., 1995). AFLP method (Vos et al., 1995) has also proved to