A New Gene that Controls Root Nodulation in Chickpea uri icon

abstract

  • Non-nodulating (Nod-) genotypes are an important genetic resource for studies of legume-rhizobium symbiosis. Investigations were carried out to determine the host genetic control of nodulation in two newly identified Nod- chickpea (Cicer arietinum) genotypes, Annigeri NN and Rabat NN, and the genetic relationship between these and other known Nod- genotypes. Annigeri NN and Rabat NN were crossed with each other, with their respective wild-type parents Annigeri (desi) and Rabat (kabuli), and with already known Nod- mutants P319-1 NN and PM233. The parents, F1, F2 and backcross progenies of the crosses were tested for nodulation by mean of a mixture of rhizobial strains in the greenhouse. Chi-square tests were conducted on the crosses to examine genetic hypotheses of monogenic and digenic inheritance. Genetic analyses of Nod- × Nod+ crosses showed a monogenic recessive gene action for non-nodulation in both Annigeri NN and Rabat NN. Studies of Nod- × Nod- crosses indicated that the same gene controls root nodulation in Annigeri NN and P319-1 NN, and that this gene is different from the ones controlling the Nod- trait in Rabat NN and PM233. These results implied that the recessive gene controlling non-nodulation of roots in Rabat NN is different from the ones earlier identified in PM233, P319-1 NN and Annigeri NN. A new gene symbol, rn8, is proposed to be assigned to the locus producing the Nod- phenotype in Rabat NN. This is the first report of a non-nodulating gene in kabuli chickpea

publication date

  • 1998
  • 1998