The analysis of the germplasm genetic structure is the basis of management, research and utilization of such germplasm [ 3], since it is critical to identify and correctly interpret the associations between functional and molecular diversity [ 4, 5].
The optimum exploitation of heterosis requires that the available germplasm is structured into genetically diverse heterotic groups.
We confirmed (i) that the pea germplasm is structured according to major passport classes as defined by the use type, the population type, and the sowing type and (ii) that the range of genetic variability present in the Pisum sativum germplasm is high, as already pointed out by other authors [ 4, 5, 8, 9, 53].
Regarding 2H, these results confirm that the extension of LD in barley, even in highly structured germplasm, is sufficient to detect associations with markers in LD with a gene, such as VRS1, where different loss-of-function mutations lead to the same phenotype.
We develop some elements of the framework required for studying such biocultural interactions, focusing on one component of management: farmers' decisions on what to plant, and the structure of germplasm exchange among farmers.
This mini core collection is an ideal pool of diverse germplasm for studying population structure and diversity, and identifying new sources of variation for use in breeding and genomics studies in foxtail millet.
Estimation of population diversity and structure of germplasm accessions could provide pivotal information for resource management, association mapping, and crop breeding.
Finally, the SSR markers, developed in this study would be very useful for germplasm analysis, population genetic structure and phylogenetic relationships.
While previous studies identified little population structure in germplasm from West Africa through to Sudan [ 15, 29], future research using genome-wide markers may reveal additional structure in this region.
