Sugarcane Ring Spot

Figure 1. Various sizes of ring spot lesions on the upper side of the leaf. Note the irregular shaped lesions and the narrow yellow halos.
Ring spot, caused by the fungus Leptosphariea sacchari, is a disease of sugarcane that has been known to occur in Florida for over 80 years. Ring spot usually affects only the older leaves, and therefore is considered a minor disease. However, correctly identifying the disease in the field can help to reduce unnecessary chemical sprays. This two-page fact sheet outlines the symptoms and spread of the disease, as well as how to prevent and control Sugarcane Ring Spot. Written by P. Rott, J.C. Comstock, H.S. Sandhu, and R.N. Raid, and published by the Plant Pathology Department.

Sugarcane Mosaic

Figure 1. Leaves showing contrasting shades of green characteristic of sugarcane mosaic Credit: Philippe Rott, UF/IFASMosaic’s most distinctive symptom is a pattern of contrasting shades of green, often islands of normal green on a background of paler green or yellowish chlorotic areas on the leaf blade. It had not been a problem in Florida until 1996, when it was observed on CP72-2086, a major commercial cultivar, near the intersection of Hatton Highway and US 98. Presently, because of the limited acreage of CP72-2086, the disease is only a potential threat. This 3-page fact sheet was written by P. Rott, J. C. Comstock, R. A. Gilbert, and H. S. Sandhu, and published by the UF Department of Agronomy, February 2015. (Photo: Philippe Rott, UF/IFAS)

Sugarcane Ratoon Stunting

Figure 1. Reddish discoloration of vascular bundles at the sugarcane node due to the causal agent of ratoon stunting.Ratoon stunting, also known as ratoon stunting disease (RSD), is considered by many sugarcane pathologists to be the most important disease affecting sugarcane production worldwide, because it can cause 5% to 15% crop yield losses without growers even realizing their fields are infected. This 3-page fact sheet describes the symptoms, causal agent, and prevention and control. Written by P. Rott, S. Sood, J. C. Comstock, R. A. Gilbert, and H. S. Sandhu, and published by the UF Department of Agronomy, August 2014. (Photo credit: Sushma Sood, USDA)