Radish, a Drosophila mutant deficient in consolidated memory.

We have characterized the behavior and genetics of the Drosophila mutant radish (rsh gene). Initial learning of radish flies in two olfactory discrimination tests is high, but subsequent memory decays rapidly at both early and late times after training. Anesthesia-resistant memory (consolidated memory) is undetectable in radish flies 3 hr after training. The mutant shows normal locomotor activity and normal sensitivity to the odor cues and electric-shock reinforcement used in the learning tests. The radish gene maps within a 180-kb interval in the 11D-E region of the X chromosome.