GENETIC-EVIDENCE OF MUTATOR-INDUCED DELETIONS IN THE SHORT ARM OF CHROMOSOME-9 OF MAIZE .2. WD DELETIONS

Analyses of 113 putative Mutator-induced events involving the yg2 locu s of chromosome 9 revealed that 11 of these events were deletions that produce albino seedlings when homozygous. This phenotype is character istic of wd (white deficiency) deletions. All 11 wd-Mu deletions faile d to complement wd1 and pyd1 (pale-yellow deficiency). Nine of the wd- Mu deletions were analyzed cytologically. Two were found to be termina l deletions and seven were internal deletions. Two of the seven had no rmal pairing throughout the terminal region involved in the pyd1 and w d1 deletions. Because genetic tests established that deletions were pr esent in these two stocks, these deletions were probably too short to disrupt the pairing of the homologous chromosomes. Mechanisms by which the Mutator system might generate these deletions are discussed.