Soybean is grown on 1.2 to 1.4 million acres in North Carolina annually, with an average yield of 28 to 29 bushels per acre. This is the highest acreage of any row crop in the state, and North Carolina is the largest soybean producer on the east coast. Almost half of the crop is grown following small grains or vegetable crops.
Soybean diseases that have the most impact on production are generally soilborne. The most important pathogen of soybean is Heterodera glycines the soybean cyst nematode (SCN), which infests at least 60% of the North Carolina acreage and accounts for at least a 5% loss in potential production. The primary tactics for managing this pathogen are cultural practices, including rotation, selection of early maturing cultivars, and double-cropping wheat and soybean. The root-knot, Columbia lance, reniform, sting, and lesion nematodes also cause significant yield loss, but these nematodes are more restricted in their distribution. Other soilborne diseases include red crown rot, Phytophthora root and stem rot, sudden death syndrome, and charcoal rot. Foliar diseases, though common, are generally of minor importance, and the application of fungicides for their control in not generally recommended. A provisional plan for management of Asiatic soybean rust has been formulated and emergency registration of fungicides for management of this pathogen, should it be found in the US, has been applied for.
Some additional web sites:
- Soybean Disease Information Notes
- NC Soybean Producers Association
- United Soybean Board
- Society of Nematologists
More information about disease in soybean is available from the Plant Disease and Insect Clinic.