Genetic control and linkage relations of additional isozyme markers in chick-pea.

Allozyme polymorphisms of nine enzymes - aspartate aminotransferase (AAT), diaphorase (DIA), esterase (EST), formate dehydrogenase (FDH), β-galactosidase (GAL), β-glucosidase (GLU), malate dehydrogenase (MDH), malic enzyme (ME), and peroxidase (PRX) - were described in chick-pea (Cicer L.). Thirteen isozyme loci, Aat-c, Dia-4, Est-2, Est-4, Est-10, Fdh, Gal-2, Gal-3, Gal-4, Glu-3, Mdh-2, Me-2, and Prx-2, were genetically defined. Alleles of each of these isozyme loci expressed codominantly in heterozygotes and exhibited a codominant, single-locus segregation ratio in F2. The loci Est-2, Mdh-2, and Me-1 were expressed only in flower. Linkage relations were determined for these 13 and several previously defined isozyme loci. The following new genetic linkages were identified: Pgm-p (locus for plastid phosphoglucomutase) - Est-10; Ald-p1 (one of the duplicate loci for plastid aldolase) - Glu-3 - Gal-2 - Est-2,3; Gal-3 - Aco-m (locus for mitochondrial aconitase) - Prx-2,3; Gpi-c (locus for cytosolic glucosephosphate isomerase) - Fdh; and Est-4 - Me-1. This study provides further confirmation on the existence of several conserved linkage groups among Cicer, Pisum, and Lens.