Inheritance of aconitase isozymes in soybean
A six-band electrophoretic zymogram for aconitase was observed in mature soybean seeds. Among 750 Glycine max (L.) Merr. strains and cultivars examined, 10 zymogram types were identified. Genetic studies showed that the second band (Rf's of 0.35 or 0.42) and the fourth band (Rf's of 0.61, 0.63, or 0.69) in the zymograms were the products of two unlinked loci, Aco2 and Aco4, with two and three codominant alleles, respectively. Heterozygotes displayed both parental band sets without any intermediate band, indicating a monomeric structure for aconitase. The most common alleles at the two loci were Aco2-b (0.793) and Aco4-c (0.818). Linkage analyses revealed that both Aco2 and Aco4 loci are inherited independently of four other biochemical loci (Adh1, Am3, Ap, Dial). Key words: aconitase, isozymes, electrophoresis, gene locus, soybean, Glycine max.