Plant Variety Protection Act Amendments of 1993 : hearing before the Subcommittee on Agricultural Research, Conservation, Forestry, and General Legislation of the Committee on Agriculture, Nutrition, and Forestry, United States Senate, One Hundred Third Congress, first session, on S. 1406, a bill to amend the Plant Variety Protection Act to make such act consistent with the International Convention for the Protection of New Varieties of Plants of March 19, 1991, to which the United States is a signatory, and for other purposes, September 20, 1993