Fig 1.
Heat map of phenotypic correlations among morphological and agro-industrial traits.
The color assigned to a point in the heat map grid indicates the strength of a particular correlation between two traits. The level of correlation is indicated by red for positive correlations and blue for negative correlations, as depicted in the color key. PCA: pigmentation of the coleoptile by anthocyanin; PFLA: pigmentation of the first leaf by anthocyanin; PLSA: pigmentation of the leaf sheath by anthocyanin; PC: plant color; SD: stalk diameter; SS: stalk succulence; JQ: juice quality; TC: tillering capacity; STF: synchronization of tillering and flowering; LTL: length of the third leaf; PLA: pigmentation of the leaf by anthocyanin; LMC: leaf midrib color; LA: leaf angle; PS: panicle shape; PD: panicle density; LPMR: length of the panicle main rachis; LPBP: length of the primary branch of the panicle; SEP: shape and extension of the peduncle; LPF: length of the pedicelated flower; GC: glume color; FAP: formation of the awn in the palea; SP: stigma pigmentation; OP: ovary pigmentation; GC1: grain covering; GC2: grain color; SW: 1000-seed weight; PFG: presence of the forehead on the grain; EC: endosperm composition; ET: endosperm texture; EC1: endosperm color; GL: grain lustre; PCP: purple color on the pericarp; TC1: threshing capacity; CEL: cellulose; EXT: juice extraction; FBY: fresh biomass yield; FLOW: days to flowering; HEM: hemicellulose; LIG: lignin; PH: plant height; POL: sucrose concentration in juice; RSJ: reducing sugars in the juice and TSS: total soluble solids.
Table 1.
Fixed and random effects, heritability, average, minimum and maximum phenotypic values for the agro-industrial traits.
Fig 2.
Neighbor-Joining tree using phenotypic data.
Euclidean distances between the sweet sorghum accessions were calculated based on the standardized phenotypic data. The colors of the branches correspond to the six subpopulations defined according to the genealogy and the historic background of the sweet sorghum lines. I-P, II-P, III-P, IV-P and V-P correspond to the clusters identified through the Neighbor-Joining method. LIS: Landrace World Collection—ICRISAT sorghum collection; LMN: Landrace Meridian Mississippi—USDA sorghum collection; LSSM: Landrace Sorghum Seed Montpelier—CIRAD sorghum collection; ML: Modern Line; ML—EMBRAPA: Modern Line EMBRAPA; and HL: Historical Line. The scale-bar (0–0.1) represents the coefficient of dissimilarity.
Fig 3.
Neighbor-Joining tree using SNP data.
Genetic distances between the sweet sorghum accessions were calculated using the identity-by-state (IBS) coefficient. The colors of the branches correspond to the six subpopulations defined according to the genealogy and the historic background of the sweet sorghum lines. I-M, II-M, III-M, IV-M, V-M and VI-M correspond to the clusters identified through the Neighbor-Joining method. LIS: Landrace World Collection—ICRISAT sorghum collection; LMN: Landrace Meridian Mississippi—USDA sorghum collection; LSSM: Landrace Sorghum Seed Montpelier—CIRAD sorghum collection; ML: Modern Line; ML—EMBRAPA: Modern Line EMBRAPA; and HL: Historical Line. The scale-bar (0–0.1) represents the coefficient of dissimilarity.
Fig 4.
Principal component analysis using SNP data.
Plotting the first two principal components (PC1 and PC2) using SNP data. The colors of the genotypes correspond to the six subpopulations of sweet sorghum according to the genealogy and the historic background. LIS: Landrace World Collection—ICRISAT sorghum collection; LMN: Landrace Meridian Mississippi—USDA sorghum collection; LSSM: Landrace Sorghum Seed Montpelier—CIRAD sorghum collection; ML: Modern Line; ML—EMBRAPA: Modern Line EMBRAPA; and HL: Historical Line.
Fig 5.
Boxplot analysis showing the distribution of agro-industrial traits according to each cluster identified through molecular and phenotypic diversity analysis.
The upper, median, and lower quartiles of gray boxes represent the 75th, 50th, and 25th percentiles of the clusters, respectively. The vertical lines represent the variation of the clusters. Dots represent outliers. CEL: cellulose; EXT: juice extraction; FBY: fresh biomass yield; FLOW: days to flowering; HEM: hemicellulose; LIG: lignin; PH: plant height; POL: sucrose concentration in juice; RSJ: reducing sugars in the juice and TSS: total soluble solids.