Brief communication. A dominant, host plant mutation conferring ineffective nodulation in the chickpea-Rhizobium symbiosis

Abstract

Chickpea (Cicer arietinum L.) mutant PM638, a derivative of wild-type, desi chickpea line ICC 640, forms yellowish, ineffective root nodules and differs phenotypically from previously described chickpea nodulation mutants. To establish the mode of inheritance of the mutant nodule trait, and to eliminate independent chlorophyll and sterility mutations carried by the mutant, PM638 was crossed with ICC 640 and an F5 generation mutant was reciprocally backcrossed to ICC 640. Segregation analysis indicated that the mutant phenotype was conferred by a single, dominant nuclear gene mutation. In keeping with established nomenclature for chickpea nodulation genes, the mutant allele is tentatively designated Rn7.