Reaction of 111 cultivars of Triticum durum Desf. from some the world’s main genetic pools Soil-borne cereal mosaic virus

One-hundred and eleven cultivars of durum wheat (Triticum durum Desf.) representative of a large portion of the genetic diversity present in the world’s improved durum wheat gene pool were grown two seasons in a field with natural inoculum sources of soil-borne cereal mosaic virus (SBCMV) near Bologna (Italy). The materials were evaluated for resistance on the basis of symptom severity expression and Sbcmv concentration in leaves according to Das (double antibody sandwich) ELISA. Among the cultivars screened, two-year overall means ranged from 0.1 to 3.2 for symptom severity (on a 0 to 4 scale) and from 0.036 to 1.702 for ELISA absorbance values. Thirty-five cultivars showed relatively low ELISA values and very mild symptoms in both seasons. These relatively more resistant entries included cultivar Edmore and twelve of its derivatives, independently bred in Canada, France, Italy and the U.S. Twenty-one entries consistently gave ELISA values and symptom scores higher than that of cultivar Grazia, the susceptible control. Because of their extreme reactions to Sbcmv and wide adaptability, a number of the cultivars tested should prove useful for investigating the existence of pathotypes within SBCMV, and of diverse cultivar responses in regard to Furoviruses until recently considered as belonging to the same species, namely soil-borne wheat mosaic virus (SBWMV) and Chinese wheat mosaic virus (CWMV).