Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 1, 1997
Publication Date: N/A
Interpretive Summary: The genomes of lentil and chickpea have some commonality and show linkage of similar genes. This conservation of linkage groups indicates a common origin in the course of evolution. The similarities of linkage groups among the genes is an asset toward the genetic mapping of each of the species. In this study we make direct comparisons of the linkage groups of chickpea and dlentil and show commonality not only between these two species but also with the genome of pea. The practical implications are that we can use conserved portions of the genome of other legume species, particularly that of pea, to predict locations of genes in lentil or chickpea. In the development of linkage maps this information has great value.
Technical Abstract: An integrated genetic linkage map of chickpea (Cicer) has been developed that consists of 9 morphological, 27 isozyme, 10 RFLP, and 45 RAPD markers covering 550 cM. The map was made from segregation data from populations of three interspecific crosses of cultivated chickpea (C. Arietinum, 2n = 16) and a closely related wild species (C. reticulatum, 2n = 16). The linkage map has 10 linkage groups representing the eight chromosomes of chickpea. Interspecific crosses were chosen for mapping because of the extremely low level of polymorphism found within the cultivated chickpea species. Several regions of the genome were found to be slightly skewed from the expected Mendelian ratios of alleles. The map was compared with published maps for pea (Pisum) and lentil (Lens). Five regions of the chickpea map have gene orders that are similar to those found in the pea genome. The degree of similarity is somewhat less than that found between pea and lentil, which is consistent with the evolutionary distances betwee these three genera. We have also observed that lentil genomic DNA RFLP probes hybridize poorly to chickpea DNA, indicating considerable divergence of these genomes at the sequence level.