Control of common bunt of wheat under field conditions with the biofumigant fungus Muscodor albus.

Authors: Goates, Blair; MERCIER, JULIEN - Harris Moran Seed Company

Submitted to: European Journal of Plant Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/25/2011
Publication Date: 9/28/2011
Citation: Goates, B., Mercier, J. 2011. Control of common bunt of wheat under field conditions with the biofumigant fungus Muscodor albus. European Journal of Plant Pathology. 131: 403-407.

Interpretive Summary: Volatile organic compounds produced by the biocontrol fungus Muscodor albus have been shown to kill numerous fungi. Recent research demonstrated that with in vitro tests, the volatiles completely killed teliospores of the common bunt of wheat pathogen Tilletia tritici as they attempted germination. M. albus has been produced in a formulation made by growing the fungus on rye grain and then drying. This formulation was used in field studies to determine the efficacy of the fungus to control disease with seed and in furrow treatments with the fungus. For in furrow treatments the formulation was cracked into particles and applied at the rate of 4g/m. Treatments were evaluated in four replicate 2 m rows in two planting dates during two seasons beginning in early spring when soil temperatures were optimal for disease development (5C), and then approximately 3 weeks later. In the first year, treatments in the first seeding date reduced CB from 44% diseased spikes in untreated controls to 12% and 9% in seed and in furrow treatments respectively and from 6% in controls to 0% in both treatments in the second seeding date. In the second year CB was reduced from 8% in controls to 0.5% and 0.25% in the first seeding date for seed and in furrow treatments respectively, and from 0.75% in controls to 0% in both the treatments in the second seeding date. It appears M. albus could have potential for CB control in organic production where control options for this disease are very limited.

Technical Abstract: Field experiments were conducted to evaluate the biological control potential of the fungus Muscodor albus, when applied as a seed treatment or an in furrow soil treatment, for control of common bunt (CB) of wheat caused by Tilletia caries. For seed treatments, dry rye grain culture of M. albus was ground into powder and applied, at a rate of 125 mg /g seed, to wheat seed infested with T. caries teliospores. The culture was also cracked into particles and applied in furrow at the rate of 4g/m of row, along with teliospore infested seed during planting. Treatments were evaluated during two growing seasons and two planting dates beginning in early spring when soil temperatures were optimal for disease development (5-10°C), and then approximately 3 weeks later. In the first year, treatments in the first seeding date reduced CB from 44% diseased spikes in untreated controls to 12% and 9% in seed and in furrow treatments respectively, and from 6% in controls to 0% in both treatments in the second seeding date. In the second year CB was reduced from 8% in controls to 0.5% and 0.25% for seed and in furrow treatments respectively in the first seeding date, and from 0.75% in controls to 0% in both the treatments in the second seeding date. M. albus may have potential for CB control in organic wheat production where options for managing the disease are very limited.