Spikelet and Floret Naming Scheme for Grasses with a Spike Inflorescence

Effective schemes to name uniquely and define parts of grass plants allow researchers to communicate results of their experiments accurately and precisely. Naming schemes for vegetative parts of grass plants have been developed; however, no system exists to name uniquely parts of the inflorescence. In this report, we present a method to extend existing systems to name parts of grass spikes. Spikelet positions are denoted by the letter S and numbered acropetally along the rachis. For example, the third spikelet position from the base of the rachis is named S3. Likewise, floret positions along the rachilla are named F (or C after fertilization) and numbered acropetally from the base to tip. The second caryopsis (floret) in the spikelet at the third spikelet position on a spike would be named S3C2. This simple scheme, when combined with the system for naming tiller, leaves, and roots, will allow all plant parts to be named uniquely. If the caryopsis in the previous example was produced on the tiller formed in the axil of the first leaf on the main stem, the complete description of the caryopsis is T1S3C2. Using this system, researchers and practitioners can communicate precisely findings on development, growth, and functional characteristics of plants and plant parts.