Each mutation produced by Yu's laboratory is delivered to the Council of Agriculture's Agricultural Research Institute for isolated field testing under rigorously controlled conditions (to prevent seeds from escaping and "contaminating" normal rice crops). After two generations of breeding, the seeds are collected and delivered to the national Mutant Library for safekeeping.
余淑美的實驗室所製造的每一個突變種，皆交由農委會農試所團隊在台中進行防護嚴密的「隔離田間試驗」（以免種子外洩、「污染」正常稻作），經過兩代繁衍收取種子後，再交付國家種原庫保存。