The Commissioner of Agriculture and Commerce of the State of Mississippi, is authorized and empowered to enter into an agreement and execute any contract pursuant thereto, with the secretary of agriculture of the United States for the purpose of, and providing for, inspection, by the Commissioner of Agriculture and Commerce of the State of Mississippi, of superphosphate, liming materials and seed furnished to producers by the department of agriculture of the United States as grants-in-aid to producers under its soil conservation program.