What is the structure of the inflorescence in Sporobolis spp.?

The structure of the inflorescence in Sporobolus species is characterized by being included within sheath with one-flowered spikelets. This means that the spikelets are tightly enclosed and only a single flower is present in each spikelet, which is a distinctive feature of this genus. The enclosed nature of the spikelets helps protect the reproductive parts of the flower, allowing it to efficiently produce and disperse seeds in its often dry habitats. This inflorescence structure is crucial for the plant's adaptation to its environment.

Other structures mentioned, such as open panicles, long slender forms with awned glumes, or dense bouquet formations, do not accurately represent the morphology typical of Sporobolus. These alternatives might describe other grass genera but not Sporobolus, which is why option B stands out as the correct description of its inflorescence structure. Understanding this specific morphology is essential for proper identification and ecological study of these plants in their wild habitats.