more... > Plant Diagnostic Center > Fact Sheets > Agronomic Crops > Blast of Rice [Image: rice blast disease] Blast is the most important disease of rice worldwide and the second most important in Louisiana. Yield losses as high as 75 to 90 percent have been observed in Louisiana due to this disease. Use this fact sheet to help you identify and manage rice blast. (PDF Format Only) Louisiana Plant Pathology: Strategies for Sampling Plant-Parasitic Nematodes in Field Crops [Image: sampling for nematodes] Plant-parasitic nematodes attack every field crop grown in Louisiana, including cotton, soybeans, corn, milo, rice, sugarcane, sweet potatoes and wheat. There are certain times of the year when nematode samples should be collected. The best time usually is during fall or early winter. Sampling time, procedures and handling included. (PDF Format Only) Nematode Management in Louisiana Sweet Potato Production [Image: nematodes in sweet potatoes] Plant-parasitic nematodes can damage plants in many ways and are considered to be a serious threat to sweet potato production in Louisiana. This publication describes problematic nematode species and management strategies available for these pests. (PDF format only) Louisiana Plant Pathology: Sclerotial Blight and Circular Spot of Sweet Potato [Image: sweet potatoes] Sclerotium rolfsii is a soilborne fungus that causes southern blight on a wide variety of plants. Proper identification is the key to successful disease management. This fact sheet is intended to aid in the identification and management of Sclerotial Blight and Circular Spot. (PDF Format Only)  more articles... Sweet Potato Diseases Provides information and symptions related to several common diseases in sweet potatoes.