Which spikelet is typically sessile and fertile in Andropogoneae?

In the Andropogoneae tribe, the lower spikelet is typically sessile and fertile. This characteristic is significant because it allows for effective reproduction and dispersal of seeds, making the lower spikelet more crucial for the plant's life cycle. The fertility of the lower spikelet contrasts with the upper one, which is often reduced or sterile, meaning that it does not produce seeds and may play a role primarily in attracting pollinators rather than contributing directly to reproduction.

Understanding this structure is essential for identifying members of the Andropogoneae and discerning their reproductive strategies. Many grass species exhibit variation in their spikelet structures to adapt to different ecological niches, and recognizing which spikelet is fertile can aid in proper identification during field studies.