Efficacy of Seed Treatment Fungicides for Agronomic Crops in Ohio

Patrick E. Lipps, Anne E. Dorrance, Landon H. Rhodes and Dennis R. Mills
Department of Plant Pathology
The Ohio State University

Seed treatment fungicides are useful tools to manage seed and soil borne pathogens. Seed treatments are highly recommended in Ohio on seeds of  corn, soybeans, small grains and alfalfa. However, a specific fungicide will not control all of the pathogens that may be present. It is important that agronomic crop producers know what the pathogens are in specific fields in order to choose the best fungicide or combination of fungicides for that field. In addition, the correct choice of fungicide will also limit losses due to seed-borne pathogens. The same rule applies in that specific fungicides will not effectively control all seed-borne pathogens. Refer to Extension Bulletin 639 Seed Treatment for Agronomic Crops for more detailed information concerning seed and seedling diseases affecting field crops in Ohio.

The following tables list the effectiveness or efficacy of fungicide seed treatments for  corn, soybeans,  small grains and alfalfa. These tables are based on field trials where these fungicides have been evaluated under very high disease conditions. The listed products may be applied in various combinations within limits of the label. Using combinations of fungicides will broaden the effectiveness against several different diseases.

Disclaimer

 The information provided herein is supplied with the understanding that no discrimination is intended and no endorsement by the Ohio State University Extension is implied.  The authors have assembled the most reliable information at the time of publication.  Due to changing laws and regulations, the Ohio State University Extension assumes no liability for the recommendations.

Relative efficacy of commercial fungicide seed treatments for control of certain diseases of 

CORN in Ohio

Trade Name Active Ingredient

Soil-borne

Seed-borne
Fusarium Rhizoctonia Pythium damping off Fusarium
Allegiance Metalaxyl N N E N
Apron XL Mefenoxam N N E N
Dynasty Azoxystrobin ND ND ND G
Maxim Fludioxonil G G N G
Trilex Trifloxystrobin ND ND ND G

 Efficacy based on labeled rates of active ingredient for each material
 Efficacy rating scale: E=excellent, G=good, F=fair, P=poor, N=no activity, ND=no data       
   

 

Relative efficacy of commercial fungicide seed treatments for control of certain diseases of 

SOYBEANS in Ohio

Trade Name Active Ingredient Phomopsis seed rot Phytophthora damping off Pythium damping off Rhizoctonia seedling blight
Allegiance Metalaxyl N E* E N
Apron XL Mefenoxam N E* E N
Maxim Fludioxonil E N N G
SoyGard Metalaxyl, Azoxystrobin P F G G
YieldShield Bacillus pumilus N N N F

 Efficacy based on labeled rates of active ingredient for each material.
 Efficacy rating scale: E=excellent, G=good, F=fair, P=poor, N=no activity, ND=no data
* Control of Phytophthora damping off only at the higher labeled rates. Low rates of Metalaxyl and Mefenoxam do not control Phytophthora but  they do control Pythium.

 

Relative efficacy of commercial fungicide seed treatments for management of certain diseases of 

WHEAT and BARLEY in Ohio

Product Active Ingredient Loose smut Common Bunt Stagonospora nodorum Fusarium  (scab) Pythium damping off
Allegiance Metalaxyl N N N N E
Apron XL Mefenoxam N N N N E
Dividend XL Difenoconazol, Mefenoxam E E E G E
LSP Flowable Fungicide TBZ N G P G N
Maxim 4FS Fludioxonil N N N G N
Raxil-Thiram Tebuconazole, Thiram E E E G F
Raxil MD Tebuconazole, Metalaxyl E E E G E
Raxil XT Tebuconazole, Metalaxyl E E E G E
RTU Vitavax-Thiram Carboxin, Thiram G G F G F
Vitavax 200 Carboxin, Thiram G G F G F

 Efficacy based on labeled rates of active ingredient for each product.
 Efficacy rating scale: E=Excellent, G=good, F=fair, P=poor and N=no activity

Relative efficacy of commercial fungicide seed treatments for control of certain diseases of 

ALFALFA in Ohio.

Trade name Active ingredient Phytophthora damping off
Allegiance Metalaxyl E
Apron XL Mefenoxam E
Maxim Fludioxonil N
Thiram Thiram N

 Efficacy based on labeled rates of active ingredient for each material
 Efficacy rating scale: E=excellent, G=good, F=fair, P=poor, N=no activity