Genetic Diversity among Lathyrus ssp. Based on Agronomic Traits and Molecular Markers

Abstract

Grasspea (Lathyrus sativus L.) and its relatives are considered resilient legumes due to their high ability to cope with different stresses. In this study, the genetic diversity of three Lathyrus species (L. sativus, L cicera and L. ochrus) was assessed by agronomic traits and molecular markers (Simple Sequence Repeat-SSR) in order to detect accessions useful for future breeding strategies. Phenotypic traits showed a high significant variation in which 1000 seed weight (1000 SW) and protein content appeared the most discriminant, as observed by principal component analysis (PCA). SSR analysis was able to detect forty-eight different alleles with an average of 9.6 allele per locus, and a Polymorphic Information Content (PIC) and a gene diversity of 0.745 and 0.784, respectively. Cluster analysis based on agronomic traits as well as molecular data grouped accessions by species but not by geographical origin. This result was confirmed by Principal Coordinates Analysis (PCoA) and Structure Analysis as well. Moreover, genetic structure analysis revealed a high genetic differentiation between L. ochrus and the other species. Analysis of MOlecular Variance (AMOVA) displayed a greater genetic diversity within species (77%) than among them (23%). Finally, a significant positive correlation was observed between agronomic and genetic distances (Mantel’s test). In conclusion, the variability detected within accessions in each species and the differences among species may be useful to plan next breeding programs, focusing on biomass production as well as protein content.