The first season of use in Mid-South rice fields has been a good one for Bayer CropScience's new Stratego fungicide. Company officials report they sold all of their launch-year supplies, and even though it's too soon to evaluate the 2002 outcome, they are confident the control provided will make a significant difference in yield and quality.

“This is a very unique chemistry with unique characteristics to give growers two methods of defense and more benefit,” said Bayer CropScience market manager Rick Kraus. Stratego combines the “locked-in” fungicide power of trifloxystrobin (TFS) and the systemic properties of a triazole. The product contains equal amounts of the active ingredients propiconazole and TFS.

With 16 label registrations for Stratego use already granted and another five anticipated, Kraus said Stratego just about covers the gamut for disease control, especially for rice. It controls sheath blight and blast as well as secondary diseases, including brown spot, narrow brown leaf spot, kernel smut and leaf smut and suppression of false smut.

“With a high affinity for the waxy layers of the plant and unique redistribution properties, Stratego can provide growers with better disease control,” said Kraus, who compared the product's affinity for the plant as being as strong as “steel to a magnet.”

Kraus said the product also has an excellent rainfastness. “It is generally absorbed in the plant within two hours, which is important, especially in the Delta.

“By having two different modes of action killing the disease, Stratego can provide built-in resistance management,” said Kraus.

Plant pathologist Gabe Sciumbato with the Delta Research and Extension Center in Stoneville, Miss., has tested Stratego and Bayer CropScience's other new rice fungicide, Gem.

Sciumbato said by putting two different chemistries in one product, the use of Stratego could help avoid the development of fungi which are resistant to certain fungicides. The plant pathologist said Stratego controls sheath blight. He added, however, that Stratego applied early enough in the season for optimum sheath blight control could be gone from the plant before kernel smut appears, so growers would need to watch their fields closely and proper timing of the fungicide will be important.

Keith Vodrazka, field development representative for Bayer CropScience's Southern region, said Stratego was tested in 28 trials in the Mid-South and Texas before the product's launch this season,

“We have trials where we inoculate the plants with sheath blight and evaluate our product under heavy disease pressure. We are trying to do our research very similar to how our university counterparts do it,” said Vodrazka.

“We believe Stratego will be an excellent choice for growers because it is broad spectrum, controlling not only sheath blight, but secondary diseases as well. We have seen improved yields and milling quality where it is used,” said Kraus.

Stratego can be applied by ground or air, but must be applied before heading. Use rates are 14 to 16 ounces per acre for effective control of major rice fungal diseases.

Sciumbato said he's seen comparable sheath blight control with early applications of Stratego when compared to other brand fungicides, and added that as is the case with all effective fungicides, the choice of which one to use will come down to a matter of economics.

Bayer CropScience's other new offering on the rice fungicide market is Gem, a broad spectrum, foliar fungicide to control rice blast and sheath blight. Its single active ingredient is TFS. “As good as Gem is against sheath blight, we have found it to be exceptional for blast control,” said Kraus. “Gem controls fungal disease by interfering with respiration in plant fungi and Gem inhibits spore germination and mycelail growth.”

Gem can provide fungal disease control for up to 21 days.

TFS, the active ingredient in both fungicides, is a reduced-risk chemistry.