Abstract: The malate dehydrogenase (MDH) isozymes in three races of Apis rnelliferaligustica——Zheiiang Agricultural University A (A), Hubei A. m. ligustica (B) and A. m. ligustica introduced from Italy ? were analyzed with polyacrylamide gel isoelectrofocusing (IEF). There were three zones (MDH I, MDH II and MDH Iil) in these electromorphs. MDH II was coded by three alleles: a, b and c. About 120 worker bees of each racewere analyzed. Theoretically, there should be six genotypesin MDH Il (a/a, b/b, c/c, a/b, b/c and a/c), but b/b type was not found in the experirncnt. The other five genotypes appeared in A, and only three (a/c, b/c and c/c) were found in B and C. Statistical analysis showed that there were significant differences in the genotype frequency, the allele frequency and the heterozygous degree between A and the other two races. This result provided a genetical and biochemical evidence for the establishment of race A.

Key words: Apis mellitera ligustica——malate dehydrogenase——allozymes