Evaluation of field resistance to brown stripe disease in novel and major cultivated sugarcane varieties in China

Brown stripe is a major fungal disease damaging the leaves of sugarcane. Breeding and cultivating resistant varieties is the most economical and effective method of controlling the disease. The paper reports on the evaluation of sugarcane brown stripe resistance in novel varieties bred by the China Sugarcane System and major varieties under cultivation in the sugarcane cultivating region. Field resistance against brown stripe was identified in 60 novel varieties and in 31 major varieties under cultivation in Lincang, Puer, and Yuxi, in Yunnan Province, and in Yizhou, Guangxi Province, where the incidence and severity of brown stripe is particularly high. Field surveys showed that 32 (53.3%) of the 60 novel varieties were highly resistant to moderately resistant, and 28 (46.7%) were susceptible to highly susceptible. In addition 21 (67.7%) out of the 31 major cultivated varieties were highly resistant to moderately resistant, and 10 (32.3%) were susceptible to highly susceptible. We recommend the intensifying of efforts to eliminate the major varieties that are susceptible, and promotion of the adoption of elite resistant varieties in wet and rainy sugarcane cultivating regions with high incidence and severity of sugarcane brown stripe disease, to effectively manage the brown stripe epidemic.