Resistance to pokkah boeng disease in new and main sugarcane varieties cultivated in China

Pokkah boeng is an epidemic fungal disease that greatly affects the development of the sugarcane industry in China. Resistance to pokkah boeng disease differs among sugarcane varieties. Breeding and planting resistant cultivars is the most economic and effective measure for controlling this disease. In this study, new sugarcane varieties bred by sugarcane research units in China and the major varieties cultivated in various sugarcane areas, were screened to find new elite pokkah boeng-resistant varieties for application in sugarcane production. Sixty new varieties resistance to pokkah boeng disease were evaluated in regionalized experiments under field conditions. Meanwhile, the resistance of the 31 main cultivated varieties was analyzed under field conditions in Lincang, Puer, and Yuxi, Yunnan Province, and in Yizhou, Guangxi Province, where the incidence of pokkah boeng is particularly high. Field surveys showed that 35 (58.3%) of the 60 new sugarcane varieties were highly resistant to moderately resistant, and 25 (41.7%) were susceptible to highly susceptible. Of the 31 main cultivated varieties, 15 (48.4%) were highly resistant to moderately resistant, and 16 (51.6%) were susceptible to highly susceptible. The results suggested that, in wetter and rainy sugarcane cultivation areas with high incidence of pokkah boeng disease, it is necessary to increase efforts to eliminate the susceptible major cultivated varieties and promote the cultivation of novel resistant varieties. This will help to achieve a reasonable distribution of varieties, fundamentally control the outbreak of pokkah boeng disease, and facilitate the high-quality development of the sugarcane industry in China.