Morphological and molecular diversity of Tunisian chickpea.

摘要

The objective of this study was to evaluate the genetic diversity and relationships among 6 new improved lines, one spring landrace and 6 varieties of winter chickpea (Cicer arietinum L.). To achieve this, 16 polymorphic simple sequence repeats (SSRs) were used in the DNA analysis. A total of 554 bands were generated with an average of 2.16 detectable bands/primer/genotype. The within-genotype genetic dissimilarity coefficient ranged from 13.0 to 77.7. Cluster analysis indicated that most genotypes could be clustered into four groups according to their geographic origin, selection objectives or pedigree. Moreover, morphological analyses generated clusters similar to those generated by molecular studies. Indeed, a comparison of morphological and molecular data using the Mantel test showed a highly significant correlation (r=0.554, P<10-5), indicating that SSR primers used in this study likely cover a vast area of the chickpea genome or might flank chromosome regions that control quantitative traits or resistance to Ascochyta blight or wilt. This also means that different combinations of alleles might reproduce similar morphological traits. In this sense, the two methods showed a low degree of variation among analysed genotypes, indicating the narrow genetic base of Tunisian chickpea germplasm. It also showed that the Tunisian chickpea collection should be increased by increasing diversity by importing new genotypes or by inducing mutations which could be used for future breeding programs.