ABSTRACT
Many variations of classical breeding procedures have been employed for improvement of self pollinating crop species. They are dictated mainly by the crop species involved, the production environment, breeding objectives and priorities and financial constraints. The breeding system followed in the cooperative USDA-Nebraska winter wheat improvement program is discussed. Traditional breeding programs in the naturally self-fertilizing species differ considerably from those utilized with the naturally cross-fertilizing species. Most population improvement programs in self-fertilizing species have relied on the accumulation of many improve homozygous genotypes within a heterogeneous population, either by natural or artificial selection. Utilization of exotic germplasm for improvement of seed yield has received little emphasis in soybean breeding. Progress in plant breeding has often been rapid when the breeding objective is defined clearly and there are simple tests available to measure progress toward an objective. Progress in plant breeding is dependent upon two factors: the amount of genetic variability available and the efficiency of the selection methods employed.
