Leaf Scald Disease of Sugarcane:A Review on the Detection Methods and Diagnostic Challenges

Leaf scald (LS), caused by Xanthomonas albilineans, is a major bacterial disease of sugarcane with widespread distribution and severe economic impact. The disease occurs in chronic and acute forms, often remaining latent for extended periods, which facilitates its spread through symptomless seed cane. Conventional management strategies rely on healthy planting material, resistant cultivars, and cultural or chemical interventions; however, these measures are constrained by variable symptom expression, limited resistant varieties, and recurrent recontamination. Early and accurate detection of X. albilineans is therefore critical for disease control. Traditional diagnostic approaches, including culture-based methods, serological assays, and PCR, provide useful tools but are hindered by low sensitivity, long processing times, and laboratory requirements. Advances in molecular assays such as nested PCR, quantitative PCR, and loop-mediated isothermal amplification (LAMP), along with emerging biosensor technologies, have improved detection accuracy and sensitivity. Nonetheless, challenges remain for their routine use in field settings due to equipment costs, technical complexity, and sample preparation needs. This review highlights current detection methods, their limitations, and prospects for portable, low-cost diagnostic platforms, including LAMP and electrochemical biosensors, which hold promise for early, on-farm detection and improved management of leaf scald in sugarcane.