Phylogenetic Relationships Among the "True Citrus Fruit Trees" by Glutamate Oxaloacetate Transaminase Isozymes Analysis.

Abstract

Leaf isozymes of glutamate oxaloaceate transaminase (EC 2.6.1.1; GOT) in the true citrus fruit trees group of Citrinae were analyzed using polyacrylamide gel electrophoresis to elucidate phylogenetic relationships among them. Segregation at each of three loci, Got-1, Got-2 and Got-3 of GOT isozymes in the progenies obtained from intergeneric crosses between Citrus and Microcitrus species followed a simple Mendelian inheritance, suggesting that Microcitrus and Citrus species have similar genetic systems and the species of these two genera are closely related to each other. Some common alleles at the three loci controlling GOT isozymes were recognized between the genera of true citrus fruit trees. These findings suggest that a genetic identity is conserved among the true citrus fruit trees group; even some of them climatically, geographically and reproductively isolated.