Abstract
Among 194 chromosomes 3 tested, 48.2% were lethal, 13.4% semilethal, 14.4% subvital, and 29.4% non-lethal. The genetic load in the population is high since only about 30% of the chromosome did not reduce viability, and the frequency of drastic (lethals and semilethals), 56%, is among the highest reported for the chromosome. The frequency of lethals is also high. The rate of allelism is low, only 0.5% among the 28 lethals tested. There were, however, 5 probable cases of pseudoallelism in which some non-allelic lethal chromosomes were either semilethal or subvital in the heterozygous condition.
