In this subtitle the following words have the meanings indicated. “Certified Irish potatoes”, when intended to be used for propagation purposes, means Irish potatoes and parts of them which conform to the standards fixed by the Secretary in classifying and determining what shall constitute “certified” potatoes for propagation purposes and in conformity with the rules and regulations established by the State in which the potatoes are grown. “U.S. No. 1 Irish potatoes”, when intended to be used for propagation purposes, means Irish potatoes and parts of them which conform to the standards issued by the United States Department of Agriculture for “U.S. No. 1” potatoes, when intended to be used for propagation purposes.