A new recessive etched endosperm kernel mutant was found segregating on the selfed ear of a Mutator outcross plant (87-2352-23) grown in Donald S. Robertson's nursery. The mutant was given the designation et*-2352. When seedling tested, mutant kernels gave rise to off-white albino seedlings, with occasional greening of leaf tips. Some mutant seedlings had fine, green revertant sectors typical of Mu-induced seedling mutants. Upon further propagation, stable lines were obtained. Mutant seedlings die after the kernel nutrient reserves are exhausted. Outcrosses of heterozygous mutant plants were placed in Patrick Schnable 's TB block, and crossed by a series of B-A translocations involving 19 of the 20 chromosome arms. Only crosses by TB-2Sb uncovered the mutant endosperm phenotype. Nonmutant kernels from the positive TB test ears were sown in the sand bench, and gave rise to seedlings segregating for off-white albinos (putative hypoploids). Mutant kernels from the same ears gave rise to green seedlings (putative hyperploids) as expected. We conclude that et*-2352 is located on the short arm of chromosome 2, distal to the TB-2Sa breakpoint. Since there are no other mutants with this phenotype located on the short arm of chromosome 2, we have given this mutant the designation etched2 (et2).
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