Charcoal Rot

Charcoal Rot

Charcoal rot is caused by the fungus Macrophomina phaseolina (Tassi) Goidanich. The fungus has a very broad host range that includes sorghum, corn and soybeans. Stalk rots, including charcoal rot are considered some of the most serious diseases of sorghum and corn in Nebraska. The first statewide survey to determine the incidence of this disease in Nebraska was conducted in 1940. At that time it was discovered in 18% of the fields sampled were infected with M. phaseolina, with varying degrees of severity. The fungus survives between crops as sclerotia. Viability of sclerotia can be maintained up to 16 months (2-3 years? Comp.). Sclerotia are released into the soil as plant debris decays. Sclerotia germinate under conditions of high soil temperature (30^oC or higher) and low soil moisture. Infection hyphae produced from sclerotia grow through the soil and infect underground plant parts.

Symptoms

Initial symptoms develop on roots and appear as water-soaked lesions. The lesions turn brown or black with age. The fungus continues to invade plant tissue from the crown up and causes similar water-soaking and discoloration in the pith. The pith eventually disintegrates leaving only the vascular strands in tact. Numerous, small, black sclerotia form on these strands and are easily visible when stalks are split open. The most characteristic outward symptom of the disease is lodging. This often occurs in the driest part of the field. Other yield depleting factors associated with lodging are poor grain filling and premature ripening. In addition to lodging, bleaching of outer stalk tissue may also be evident.

Plant Health Management

Crop Rotation.

Resistant Varieties

Drought-tolerant and lodging-resistant grain sorghums restrict (suppress) charcoal rot development. Sweet sorghums and forage sorghums are resistant to charcoal rot.

Avoid high plant populations

Maintain Adequate Fertility

Avoid high nitrogen levels and low potassium levels.

References

Cook,G.E., M.G. Boosalis, L.D. Dunkle and G.N. Odvody. 1973. Survival of Macrophomina phaseoli in corn and sorghum stalk residue. Plant Dis. Reptr. 57:873-875.

Frederiksen,R.A. 1986. Compendium of sorghum diseases. American Phytopathological Society, St. Paul, MN. 82 pp.

Livingston, J.E. 1942. Charcoal rot of corn and sorghum in Nebraska. Plant Dis. Reptr. 26: 50-52.

Nyvall, R.F. 1989. Field crop diseases handbook, 2^nd. Ed. Van Nostrand Reinhold, New York. 817. pp.

Highlighted Area

Expanded name from the compendium is Macrophomina phaseolina (Tassi) G.Goid. (syns. M. phaseoli (Maubl.) Ashby and Botryodiplodia phaseoli (Maubl.) Thirum.). Butl. anamorph Rhizoctonia bataticola (Taub.) Butl. (syn. Sclerotium bataticola Taub.)

Useful Links

Texas A&M University

Caveat

This description is presented for information only and no endorsement is intended for products listed, nor criticism meant for products not mentioned. Always consult the product label before purchasing and using any pesticide.

Material contained on the Links from the page are the responsibility of the linked page's author(s).

This page was drafted by: Jane Christensen, Department of Plant Pathology, University of Nebraska-Lincoln

Disease images were provided by: Dr. David Wysong, Department of Plant Pathology, University of Nebraska-Lincoln

Questions, Comments, Complaints and Complements?

This page is authored and maintained by:
Dr. J.E. Partridge, Department of Plant Pathology, University of Nebraska-Lincoln

E-Mail Home Page