Hypoploid test to locate defective kernel mutants on 8S or 8L proximal to TB-8Lc breakpoint

The defective kernel mutant collection has been tested for arm location by a set of B-A translocations which cover nineteen chromosome arms (all except the short arm of chromosome eight). Those receiving a full test but still not located were thought to be located either proximal to the breakpoint of one of the 19 arms or on the short arm of chromosome eight. Mutants that are actually located on the short arm of chromosome eight or on the long arm proximal to the centromere can be identified by selfing the hypoploids grown from the TB-8Lc translocation cross. Since the deficient AB chromosome will not transmit, only the normal chromosome eight, carrying the mutant allele, forms viable gametes. Among 35 defective kernel mutants studied in this manner, six showed a higher mutant proportion than the 25% expected from a normal self. The transmission data in Table 1 showed that the mutant frequencies ranged from 62% to 100%.

Table 1.

Ming T. Chang and M. Gerald Neuffer

Please Note: Notes submitted to the Maize Genetics Cooperation Newsletter may be cited only with consent of the authors.

Return to the MNL 60 On-Line Index
Return to the Maize Newsletter Index
Return to the Maize Genome Database Page