Analysis on Resistance to Scab of New Wheat Varieties (Lines) in Shaanxi Province

Wheat scab is one of the important diseases in China,and growing resistant varieties is the preferred way for control of this disease.To determine the resistance of new wheat varieties(lines) in Shaanxi province during 2005-2007,531 varieties(lines) were identified by artificial inoculation.The results showed that there were no immunity varieties,and 7 varieties(lines) were resistant with ratio of 1.32%;26 varieties(lines) were middle-resistant with ratio of 4.90%;the remained 498 varieties(lines) were middle-susceptible to susceptible and the ratio was 93.78%.All of the disease index were 100%.Also,resistance of 344 varieties(lines) bred in 2005 and 2006 were identified under field artificial disease nursery,which indicated that 37 varieties(lines) were resistant with ratio of 10.76% and disease index of 3.3%~20.0%;50 varieties(lines) were middle-resistant with ratio of 14.53% and disease index of 13.3%~66.7%;257 varieties(lines) were middle-susceptible to susceptible with ratio of 74.71% and disease index of 23.3%~100.0%.Therefore,most of these new-bred varieties were susceptible to wheat scab.Appropriate scale of identification and selection in wheat materials for resistance to scab should be made according to occurence level of wheat scab.Also,modern biological technology should be used in wheat scab-resistant breeding.