Barley somaclones associated with high yield or resistance to powdery mildew

A study was conducted to evaluate the usefulness of somaclonal variation as a means to obtain powdery mildew resistance in the background of an agrono mically elite, high-yielding barley ( Hordeum vulgare L.) cultivar. A total of 170 R-o-derived lines were regenerated from embryo-induced callus of th e barley cultivar Leger. Forty-five lines were selected and evaluated in re plicated field plots at two locations in Eastern Canada. In comparison with Leger, one of the 45 lines was higher yielding, one produced a greater tes t weight, two had a greater seed weight, and one was shorter in plant heigh t. Three lines were found to segregate for resistance to powdery mildew ( E rysiphe graminis DC ex Merat f. sp. hordei EM). Many of the single-plant se lections from the three resistant lines showed resistance to powdery mildew under field conditions for two years. Three lines were eventually promoted to the official registration tests in Ontario. One of the three lines was subsequently registered as a new cultivar (AC Malone) in Canada. To our kno wledge, AC Malone is the world's first barley cultivar selected from somacl onal variation. The results of this study demonstrate that it is possible t o obtain high- yielding or disease-resistant lines from callus culture in b arley.