**1. Introduction**

Soybean, *Glycine max* (L.) Merrill is recognized as the most important grain legume in the world in terms of total production and international trade (Golbitz, 1995), being an important source of protein and oil. There are developing thousands of breeding lines and hundreds of elite cultivars yearly in the soybean hybridization programmes over the world. The developing of these breeding lines increased genetic uniformity in the frame of species. Therefore, the genetic basis of these released cultivars is rather narrow. Generations of new and improved cultivars can be enhanced by new sources of genetic variation; therefore criteria for parental stock selection need to be considered not only by agronomic value, but also from the point of view of their genetic dissimilarity. That is why the evaluation of genetic variation is a very important task not only for population genetics but also for plant breeders. The study of genetic variation has fallen within population genetics which has focused on analyzing, measuring and partitioning genetic. The genetic diversity can be analyzed by agronomic and biochemical traits, and molecular marker polymorphisms, Analysis of gene marker data enables estimation of the mating system and monitoring of genetic changes caused by factors affecting the reproductive biology of a species. A key factor driving utilization of exotic germplasm is potential benefit. Benefit can be quite apparent for characteristics such as disease resistance or agronomic traits, but vague for yield or abiotic stress resistance.
