Mutations for necrotic roots were identified in an experiment designed to recover new mutations in the Asgrow Mutable line as evidence for transposition of a mobile genetic element (Groose and Palmer, 1987). Each of three independent mutations for necrotic roots was discovered in a different F11 family, each of which had descended from a different F9 plant of the Asgrow Mutable line. Seedlings of 1"936 F11 families were pulled from the sandbench at the second trifoliolate leaf stage and roots were examined for nonfluorescent root mutations.