Analysis of the interaction of pea (Pisum sativum L.) symbiotic genes Sym33 and Sym42 whose mutations result in abnormalities during infection thread development

Abstract

Using pea single mutant lines SGEFix−-2 (sym33) and RisFixV (sym42), which are characterized by different abnormalities during symbiotic nodule development, including thickening of infection threads’ walls, a double mutant RBT4 line, carrying a pair of symbiotic genes sym33 and sym42 was constructed. The epistasis of the mutant allele sym33 over the mutant allele sym42 with respect to the histological and ultra-structural organization of nodules was shown. Thus, it was demonstrated that the Sym33 gene functions earlier in symbiotic nodule development than the Sym42 gene.