Flavonoid-Deficient Mutants in Grass Pea (Lathyrus sativusL.): Genetic Control, Linkage Relationships, and Mapping with Aconitase and S-Nitrosoglutathione Reductase Isozyme Loci

Two flavonoid-deficient mutants, designated asfldL-1andfldL-2, were isolated in EMS-mutagenized (0.15%, 10 h) M2progeny of grass pea (Lathyrus sativusL.). Both the mutants contained total leaf flavonoid content only 20% of their mother varieties. Genetic analysis revealed monogenic recessive inheritance of the trait, controlled by two different nonallelic loci. The two mutants differed significantly in banding patterns of leaf aconitase (ACO) and S-nitrosoglutathione reductase (GSNOR) isozymes, possessing unique bands inAco 1, Aco 2,andGsnor 2loci. Isozyme loci inherited monogenically showing codominant expression in F2(1 : 2 : 1) and backcross (1 : 1) segregations. Linkage studies and primary trisomic analysis mappedAco 1andfld 1loci on extra chromosome of trisomic-I andAco 2,fld 2,andGsnor 2on extra chromosome of trisomic-IV in linked associations.