Government says the move will support local processors while keeping controls on export volumes.
The legal action comes as Syngenta also expands its biological crop and soil carbon business through a new partnership with Groundwork BioAg.
The move keeps affordable glyphosate supplies available for U.S. soybean farmers while fresh action in Europe highlights efforts to reduce fertilizer costs through biological products.
Industry leaders say imports during the harvest season could push local maize prices lower and increase pressure on growers.
USDA says the first cargoes from Morocco could arrive in New Orleans within days following the temporary removal of import duties.