Duane Rathmann

This doesn’t happen too often! A new insecticide will be available for fighting soybean aphids during the 2019 growing season.

BASF has received U.S. EPA registration for Sefina Inscalis insecticide. The new insecticide controls piercing-sucking insects while leaving many beneficial insects and pollinators alone, in row and specialty crops including soybeans, cotton and citrus.

“The great thing is Sefina is a novel mode of action that will control aphids that are resistant to pyrethroids or organophosphates. We’ve tested for those, and it works well on those populations,” said Duane Rathmann, BASF technical service rep for southern Minnesota.

The active ingredient is Afidopyropen, a new mode of action. It was discovered by the Japanese company Meiji Seika Pharma Co. Ltd and the Kitasato Institute., specifically 2015 Nobel Prize recipient Dr. Satoshi Omura, and co-developed with Meiji.

The application threshold for Sefina is 250 aphids per soybean plant. Growers will want to follow the label’s instructions for personal protective equipment as well as application instructions.

“It is not a restricted use product, but it is still a pesticide so you have to treat it like a pesticide,” he said.

BASF has not released the cost per acre for treating soybeans in 2019 with Sefina. Rathmann expected to have that information by late winter.

“We recognize the soybean aphid market and Minnesota is a key state when it comes to soybean aphids,” he said. “Along with the Dakotas, Wisconsin and Iowa, we have product reserved for that area.”

Inscalis products from BASF will also be available for the vegetable and citrus growing regions in California and Florida.

Sefina is fast acting, he added. Aphids stop feeding on the soybeans within hours, and within one or two days, they fall off. The damage stops very quickly.

A narrow range of insects, piercing-sucking insect pests, are affected by Sefina, he added. Beneficial pests are not generally affected.

In a trial conducted during the summer of 2018, Rathmann treated a field with Sefina that had very heavy aphid pressure – over 500 aphids per plant around Aug. 1.

He came back three days after application and evaluated the soybeans. There were no aphids on the leaves, but he did see some Asian lady beetles and larvae crawling on the soybeans.

“I realized this is the first insecticide treatment where I ever saw that happen,” Rathmann said. “A broader spectrum insecticide would have hurt the beneficials.”

With more beneficial insects around, spider mite flares especially in hot and dry conditions, are less likely to occur.

“People will recognize Sefina is very soft on aphid predators and bees and doesn’t have those negative side effects of some of the other insecticides,” he concluded.