GENETIC-VARIATION AND ADAPTATION OF 76 CANADIAN BARLEY CULTIVARS

A study was initiated in 1990 to determine the genetic variation and a daptation of all registered Canadian barley (Hordeum vulgare L.) culti vars. Seventy-six cultivars were tested at four locations across Canad a (Charlottetown, Ottawa, Brandon, and Bentley) in 1991 and 1992. Thes e cultivars were grouped into 10 classes and classes were compared in five categories: eastern vs. western, doubled-haploid (DH) vs. convent ional, feed vs, malting, two-row vs. six-row, and hulless vs. covered. These 76 cultivars showed remarkable variation in yield, test weight, kernel weight, plant height, and maturity and responded differently t o the environments. Among them, Albany and Chapais had the highest yie ld and they also yielded well in both Eastern and Western Canada. Thus , some barley cultivars were widely adapted across the whole country. Two-row cultivars had higher test weight and higher kernel weight than six-row and appeared to be more stable in yield over the environments . Eastern two-row cultivars were superior in yield, test weight, and k ernel weight than western two-row. Eastern two-row, in general, perfor med well across Canada. Several western six-row cultivars performed we ll in both Western and Eastern Canada. Therefore, greater exchanges of breeding materials between the two regions are recommended in order t o fully exploit the genetic potentials of new cultivars. DH cultivars yielded as well as conventional cultivars and responded similarly to t he environments. This substantiates that complete homozygosity and hom ogeneity have very little effect on the performance of DH cultivars. A mong the western two-row, feed cultivars yielded either higher than or the same as malting cultivars in the eight environments. Hulless cult ivars had lower yield, higher test weight and lower kernel weight than covered cultivars.