By Shelby Young
USA Rice
WASHINGTON, DC – The U.S. Environmental Protection Agency (EPA) has announced approval of Section 18 emergency exemptions for the use of Courier® SC (A.I. buprofezin) insect growth regulator for the control of the rice delphacid (Tagosodes orizicolus) in the rice production regions of Arkansas, Louisiana, Mississippi, and Texas. Missouri did not apply because the insect was not found there. If it is identified there, the state will apply immediately. Courier is a product from Nichino America, Inc., which research has shown to be much more effective in controlling this damaging insect than currently available insecticides labeled in rice.
Section 18 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) authorizes the EPA to allow unregistered use of a pesticide for a limited time if the agency determines that an emergency condition exists.
This is certainly the case as it relates to the rice delphacid (RD) in southern U.S. rice production. This insect is what is known as a piercing/sucking insect. Both nymphs and adults extract sap from plant phloem, depriving plants of essential nutrients. Nymphs and adults inhabit distinct areas of the rice plant, with nymphs feeding on the lower stems and adults feeding higher up on the plant. This feeding activity results in symptoms such as leaf senescence, necrosis, and a condition known as “hopperburn.” In severe cases, this can lead to extensive plant dieback, stunted growth, and substantial yield losses. The RD also can vector a damaging rice viral disease known as Hojo Blanca.
The RD was observed in Louisiana rice areas in the late 1950s and early 1960s but disappeared. It was most recently identified again in a Texas rice field west of Houston in 2015. For several years the damage from the insect was sporadic and typically observed in the ratoon crop. However, in June 2025 it was found in the main crop, again west of Houston. It caused significant damage in some main crop fields and was devastating in many ratoon crop fields.
Texas A&M rice scientists have estimated a 26 percent yield reduction caused by RD in main and ratoon crop Texas rice production in 2025. The insect also caused significant damage in northeast and central Louisiana and southeast and southwest Arkansas rice fields. The insecticides available for use in 2025 were marginal at best. However, rice scientists from Texas A&M, LSU, University of Arkansas, and Mississippi State were able to evaluate a number of insecticides on the insect and identified Courier as having high levels of control. This winter, Texas, Louisiana, Arkansas, and Mississippi applied for Section 18 exemptions for the use of Courier in rice production fields.
The significant damage potential of this pest led to USA Rice creating the Delphacid Task Force (DTF) in 2025. The DTF is made up of researchers, extension scientists, farmers, consultants, and others from the southern U.S. rice producing states.
“The Delphacid Task Force has been very successful in coordinating and facilitating the response to this insect,” said USA Rice’s Dr. Steve Linscombe who spearheaded the DTF. “In addition, during the recent USA Rice D.C. Fly-in in February, producers and others met with the EPA to stress the urgent necessity of the Section 18s and urge the agency to expediate the review process. The rice industry is also appreciative of Sen. John Kennedy (R-LA), a member of the Senate Appropriations Committee, who recently wrote a letter to EPA Administrator Lee Zeldin to encourage the timely consideration of the Section 18 requests.”