ABSTRACT
The concept of germplasm is inherently simple, yet extremely complex in scope. Germplasm, as defined for a crop, represents all the different genotypes that could be used for improvement. Improvement is accomplished traditionally by making sexual crosses between individuals and then selecting plants with the desired characteristics, such as disease or stress tolerance or resistance. With the advent of more exotic techniques, such as transformation and protoplast fusion, virtually any species may be modified by incorporating a gene or genes from an unrelated species. Thus, germplasm for a crop becomes more expansive. Nevertheless, we usually consider germplasm more narrowly to be the gene pool from those individuals that are related and may intercross. Germplasm is valuable because it contains the diversity of genotypes that are needed to develop new and improved lines.
