SORGHUM STUDY Sudangrass (2 images), Sorghum-Sudangrass (2 images) & Sorghum (2 images)

Typical seed morphological fractions of (a) sudangrass, (b) sorghum–sudangrass hybrid, and (c) sorghum. From left to right: spikelets, glumes, caryopsis

Sorghum x almum Black Sorgo, Almum Grass, Almum Sorghum Poaceae

Colors are yellow to black and mixtures in between. Lemma and palea are thin and not visible. Pedicel and rachis segment: mixture of fractured and intact. Surface Texture Some hair on pedicels and rachis segments; spikelet smooth. Some spikelets disarticulate by fracture and others by abscission. This is a characteristic that is between that of S. halepense and S. x drummondii. The size is also intermediate but natural variation puts individual units into larger and smaller species. The caryopsis is round on top.

Sorghum halepense Johnson Grass Poaceae

Brown, light to black with gradiations. Lemma and palea are not visible. Intact rachis segment and pedicel and smooth spikelet base. Surface Texture Spikelet smooth and shiny; sparse hairs on appendages. The units are mostly found as spikelets with the separation between spikelets by a clean disarticulation at the bases leaving no fragments. Therefore the rachis segment and pedicel are usually intact with cuplike structures at their apexes. The caryopsis has a rounded apex.

Sorghum bicolor Sorghum Poaceae

Colors are white, red or black. Lemma and palea are not visible. Fractured remnants of pedicel and rachis segment at base. Surface Texture Smooth and glabrous. Units of this species can be sold as spikelets or caryopsis depending on the type. Grain sorghum varieties are usually caryopsis while broomcorn units are spikelets. Spikelets are separated by fracturing the pedicels and rachis segments.

Sorghum x drummondii Sorghum Sudan Grass Hybrids Poaceae Sorghum x drummondii Sudan Grass Poaceae

Colors are yellow to black with some reddish and some mixed. Lemma and palea are thin, mostly not seen. All pedicels and rachis segments fractured, no abscission. Surface Texture Mostly glabrous; smooth. Seed Type Spikelet. All the disarticulation by this species is by fracture. There is no sign of an abscission crease at the base of the spikelet. The caryopsis is less rounded at the apex where the slope is more gradual from the middle to the top.