Barley is an economically important cereal crop throughout most of the world. The study and elucidation of the genetic complex of this plant will add to its extensive usefulness to man, and will also provide valuable information for similar research projects on other crop plants.

The development of new and better varieties of plants through plant breeding is essential to meet certain needs of a changing world. Genetics and a knowledge of its principles are the basis for such improvement. Barley has been used rather extensively in linkage relations studies. Its desirable characteristics are: (1) interspecific fertility and relative ease of hybridization, (2) numerous characters that are easily differentiated, (3) its commercial importance as a crop and (4) there are seven chromosome pairs in each of the four cultivated species.