Identification and chromosomal locations of aconitase gene loci in Triticeae species

Two systems of monomeric aconitase (ACO) isozymes, designated ACO-1 and ACO-2, were identified in Triticum aestivum and in five diploid Triticeae species. The gene loci Aco-A1, Aco-B1, and Aco-D1 were located in T. aestivum cv. 'Chinese Spring' chromosome arms 6Aq, 6Bq, and 6Dq, respectively, and the gene loci Aco-A2, Aco-B2, and Aco-D2 in 5 Aq, 5 Bq, and 5Dq, respectively. Aco-1 gene loci were also identified in 6Eβ of Elytrigia elongata, 6HL of Hordeum vulgare cv. 'Betzes', 6RL of Secale cereale 'PI 252003', 6S(1) of T. longissimum, and CSU-31 of T. umbellulatum. Other Aco-2 gene loci were identified in 5RL of S. cereale cv. 'King II' and 4EL of E. elongata. Conservation of synteny relationships is indicated among the species studied for the genes identified, with the exception of Aco-E2; the presence of this gene in 4EL suggests that E. elongata differs from 'Chinese Spring' and 'King II' by a translocation involving 4E and 5E.