Seed fungicide treatment for wheat

The office has been busy tak­ing in 4-H entry forms for the Delaware County Fair. Our Fair will open on Sep­tem­ber 17th, which is just three weeks away. We have been gear­ing up for a few weeks now. The weather is feel­ing more “fall like” and it reminds us that fall is clearly around the cor­ner. Fore­cast­ers are call­ing for near nor­mal tem­per­a­tures and below nor­mal rain­fall for these next two weeks.

Seed Fungi­cide Treat­ment for Wheat

Seed fungi­cide treat­ments may pre­vent early estab­lish­ment of dis­eases such as Stagonospora blotch and min­i­mize prob­lems with loose smut and com­mon bunt. It could also play an impor­tant role in giv­ing seedlings a good head start by pro­tect­ing them from early-season dis­eases caused by Fusar­ium, Pythium, and Rhi­zoc­to­nia species. Pierce Paul, OSU Exten­sion Spe­cial­ist in Plant Pathol­ogy says that seed treat­ments are most ben­e­fi­cial for seeds infected prior to plant­ing or when seeds are planted under cool, wet soil con­di­tions. How­ever, seed treat­ments should not be con­sid­ered a cure-all for the selec­tion of poor seed lots. They will not increase the ger­mi­na­tion of poor qual­ity seeds – seeds with exces­sive mechan­i­cal dam­age, seeds stored under poor con­di­tions, genetic dif­fer­ences in vari­ety, or other damage.

Seed treat­ments do not always increase yield, but in gen­eral, seed treat­ments result in increased yield by min­i­miz­ing stand reduc­tion result­ing from infec­tion and death of seedlings caused by soil borne pathogens. Accord­ing to Paul, pro­tec­tion is also short-lived, gen­er­ally only last­ing as long as it takes for the crop to emerge. In addi­tion, no sin­gle seed treat­ment or active ingre­di­ent is equally effec­tive against all soil borne pathogens or all pop­u­la­tions of the same pathogen. “Pro­duc­ers should select seed treat­ment based on poten­tial seed and seedling dis­ease prob­lems and the his­tory of such prob­lems in their fields.”Paul said. For instance, avoid plant­ing seeds har­vested from scab-infected fields, but if scabby seeds are used for plant­ing, then a fungi­cide with activ­ity against Fusar­ium should be selected. On the other hand, if a field has a his­tory of Pythium damp­ing off due to cool, wet plant­ing con­di­tions, a seed treat­ment prod­uct with activ­ity against Pythium should be selected.

It is highly rec­om­mended that win­ter wheat seeds be treated for con­trol of sev­eral seed-borne dis­eases, includ­ing loose smut, com­mon bunt, Stagonospora glume blotch and scab. Accord­ing to Paul, the sys­temic fungi­cides Div­i­dend Extreme and Raxil — Thi­ram, and Raxil XT have excel­lent activ­ity against both loose smut and com­mon bunt at low usage rates (a.i./ cwt). Div­i­dend Extreme is effec­tive in con­trol­ling seed-borne Stagonospora, but it is more effec­tive against seed-borne scab at the higher rate (1.0 fl. oz./cwt) than at the lower rate (0.5 fl. oz./cwt). In gen­eral, triazole-based fungi­cide such as Raxil and Char­ter, used at the labeled rates, are effec­tive against seed-borne Stagonospora and have rel­a­tively good activ­ity against seed-borne scab. Prod­ucts with Meta­laxyl and Mefenoxam are effec­tive against Pythium. “For best results and pro­tec­tion against a wide range of pathogens, seeds should be treated with mul­ti­ple active ingre­di­ents,” Paul said.

Visit the field crops dis­ease web­site for more on wheat seed treat­ment: oardc.ohio-state.edu/ohiofieldcropdisease/images/Wheat_seed_ treatment_chart_2010_rev_10_28_2010.pdf.

Rob Leeds is the OSU Exten­sion Edu­ca­tor for Delaware County.

Posted by Rob Leeds on Aug 27 2011. You can follow any responses to this entry through the RSS Feed. Comments can be made below.