Agricultural equipment spraying field at sunsetCorteva, the only U.S.-based 2,4-D manufacturer, initially petitioned to have tariffs placed on 2,4-D herbicides from India and China. The U.S. International Trade Commission agrees to advance the petition despite opposition from commodity groups.

Corteva alleges that it is being hurt by imports allegedly sold in the U.S. at less than fair value. It further claims this practice is due to subsidies from the Chinese and Indian governments.

Six of the nation’s major commodity groups, including the National Corn Growers Association, sent a letter to the U.S. International Trade Commission in April against advancing the petition. The National Corn Growers Association said the decision will impact farmers due to low corn prices and increasing input prices.

Groups opposed to the tariffs argue that America’s farmers cannot rely upon a sole domestic supplier of 2,4-D to meet nearly all of the market’s needs.

Read more on the petition to place tariffs on 2,4-D here.