Genetic structure of moroccan lentil landraces from different origins as revealed by short sequence repeat molecular markers using the software structure

The genetic structure of 252 genotypes of 53 lentil Moroccan landraces from
different geographic origins was assessed using 19 microsatellites molecular
markers. According to STRUCTURE software based on Bayesian approach,
the best genetic structure model displays two gene pools (with the Evanno ad
hoc statistic ΔK=168.167) of contrasting sizes under the assignment
probability higher than 80%. A small set of landraces, mainly from the dry
environment of Abda region, was differentiated from the rest. The largest
gene pool includes genotypes from different origins. Although, no clear
correlation was found between geographic origin and genetic structure as the
two gene pools are represented in all origins. Fifty-three percent of the
genotypes from a small location in Abda region, the driest environment
where drought and heat stresses are the most important traits targeted by
farmers over years for selection of adapted landraces, were assigned to a
small discrete gene pool. A fairly high value of ΔK (37.46) compared to other
values suggests the possibility of three gene pools displaying the two local
cultivars L56 and L24 as major components of the third gene pool with
97.6% as proportion of membership. As for the model with two gene pools,
nearly half of the genotypes from the dry Abda region was assigned to a
small discrete gene pool. These landraces have a short cycle and high early
vegetative growth vigor conferring drought tolerance.