Genetic Relationship between Sweet Grain Sorghum and the Other Sorghum Types Cultivated in Burkina Faso Assessed with Nuclear Microsatellite Markers SSRs

Abstract

In Burkina Faso, sweet grain sorghum [Sorghum bicolor (L.

Assessment of Genetic Variability of Three Types of Sorghum Cultivated in Burkina Faso Using Morphoagronomic Quantitative Traits and Brix

“…This is confirmed by the organization of genotypes into agro-morphological groups independently of the "sorghum type" factor in the hierarchical ascending classification. Similar results are reported by [18] and [17] on these sorghum types using molecular markers. Indeed, the three sorghum types generally coexist in combination in traditional production systems.…”

“…This is confirmed by principal component analysis, which revealed an association between this sorghum and these variables. Similar results on panicle width and grain weight of sweet grain sorghum and Brix are reported in previous studies [10,17]. The weak grain weight of sweet grain sorghum could be explained by its asymmetric shape and mealy consistency in contrast to the other two types, which have elliptical and glassier grains.…”

“…A gene flow could exist between them insofar as sorghum, although it is preferentially self-pollinated, has an outcrossing rate that can vary from 7-40% [20,21]. The genetic proximity between these sorghums could confirm that they belong to the same species [17]. Therefore, the only determining factor in their differentiation would be the genotype, hence the high values of coefficients of determination recorded in the study with this factor.…”

“…This is confirmed on the one hand by the Euclidean distances, which showed a smaller distance between sweet sorghums and on the other hand by the results of the hierarchical classification where a composite group consisting of all sweet grain sorghum genotypes and three sweet sorghum genotypes was obtained. [18] also showed that sweet sorghums (sweet sorghum, sweet grain sorghum) are genetically more closely related (Fst = −0.0558) to grain sorghum [17], however, showed greater proximity between sweet grain sorghum and grain sorghum using molecular markers. This difference in molecular and phenotypic proximity could be explained by the generally polygenic determinism of the traits taken into account in the estimation of phenotypic distance, which can lead to convergence phenomena [33].…”

“…To date, few studies on the genetic relationships between sweet grain sorghum and other sorghum types grown in Burkina Faso have been carried out using nuclear and chloroplast molecular markers. Although the results obtained showed genetic proximity between these sorghum types [17,18], the evaluation of these sorghums under identical cropping conditions could help identify agro-morphological and biochemical traits specific to sweet grain sorghum that could be exploited in sorghum improvement programs. Thus, the present study aims to compare the quantitative agro-morphological and biochemical characteristics of sweet grain sorghum with grain sorghum and sweet sorghum grown in Burkina Faso.…”