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Sequential functioning of Sym-13 and Sym-31, two genes affecting symbiosome development in root nodules of pea (Pisum sativum L.).

A Y Borisov·S M Rozov·V E Tsyganov·E V Morzhina·V K Lebsky·I A Tikhonovich
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Abstract

Two Fix- mutants of pea (Pisum sativum L.) which are unable to fix molecular nitrogen, E135f (sym-13) and Sprint-2Fix- (sym-31), were crossed to create the doubly homozygous recessive line, named RBT (sym-13, sym-31). The ultrastructural organization of nodules of the RBT line was compared with that of each of the two parental mutant lines and with the original wild-type genotypes of the cultivars Sparkle and Sprint-2. It was shown that the RBT line is similar to the mutant line Sprint-2Fix- in having abnormal symbiosome composition and bacteroids with relatively undifferentiated morphology. Because the phenotypic manifestation of the sym-31 mutant allele suppresses the phenotypic manifestation of the sym-13 mutant allele, it is concluded that the function of the gene Sym-31 (which is mutated in the Sprint-2Fix- line) is necessary at an earlier stage of symbiosome development than the gene Sym-13 (which is mutant in the E135f line).

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Genes, PlantMutationPisum sativumPlant RootsRhizobiumSymbiosisJournal ArticleResearch Support, Non-U.S. Gov't

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A Y Borisov, S M Rozov, V E Tsyganov, E V Morzhina, V K Lebsky, I A Tikhonovich. 1997-05-20. Sequential functioning of Sym-13 and Sym-31, two genes affecting symbiosome development in root nodules of pea (Pisum sativum L.).. https://doi.org/10.1007/s004380050456

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