CHICAGO (Reuters) - An Arkansas judge on Friday dismissed a Monsanto Co lawsuit aiming to stop Arkansas from blocking the use of a controversial farm chemical the company makes, dealing a blow to its attempts to increase sales of genetically engineered seeds.

FILE PHOTO: Monsanto logo is displayed on a screen where the stock is traded on the floor of the New York Stock Exchange (NYSE) in New York City, U.S. on May 9, 2016. REUTERS/Brendan McDermid/File Photo

Monsanto, which is being acquired by Bayer AG, filed the lawsuit last year in a bid to halt the state’s ban on sprayings of the weed killer known as dicamba from the period spanning April 16 to Oct. 31.

Growers across the U.S. farm belt said last summer that dicamba drifted away from where it was sprayed, damaging millions of acres of crops that could not tolerate the herbicides.

St. Louis-based Monsanto, the biggest U.S. seed company, said it was disappointed with the judge’s decision and would consider additional legal action.

In the ruling, Pulaski County Circuit Court Judge Chris Piazza cited a recent Arkansas Supreme Court decision that the state cannot be made a defendant in court, according to the Arkansas Agriculture Department.

Dicamba, also sold by BASF SE and DowDuPont Inc, is meant to be used during the summer growing season on soybeans and cotton that Monsanto engineered to resist the chemical.

Monsanto is banking on the herbicide and its dicamba-resistant soybean seeds to dominate soybean production in the United States, the world’s second-largest exporter. The company says dicamba, which it sells under the name XtendiMax with VaporGrip, is safe when used properly.

The Arkansas ban hurts Monsanto’s ability to sell dicamba-tolerant seed in the state and has caused “irreparable harm” to the company, according to Monsanto’s lawsuit. The state also limited use of Monsanto’s dicamba herbicide in 2017 but allowed sales of products by other companies.

David Wildy, an Arkansas farmer who served on a state task force that recommended the ban, said he supported Friday’s ruling. He said his soybeans suffered damage from the herbicide last year and that it threatens plants ranging from flowers to vegetables and peanuts when it drifts away from where it is sprayed.

“If we can’t keep products on target, then there’s not a place for them in agriculture,” Wildy said in an telephone interview.