DEVELOPMENTS IN CHLOROTIC STREAK RESISTANCE SCREENING

Chlorotic streak is a disease known for many years in the Australian sugar industry. Recent studies have highlighted its widespread occurrence and significant yield effects. Resistant varieties offer one form of disease control. Methods for screening for resistance include natural field infection using diseased infection rows, and hydroponic culture of test canes using diseased infection plants. The first Australian resistance tests were conducted in the mid- 1930s. Since that time, limited success in resistance screening has been achieved. Further improvements being addressed include a short hydroponic disease infection period in the glasshouse coupled with field expression of disease symptoms. There remains a need to supply the Queensland industry with varietal resistance information and to make refinements to our current breeding strategies.