Commelinids

Dactylis glomerata bluete2

Commelinids are a large and diverse group within the monocots, which are one of the major lineages of flowering plants (angiosperms). This group is recognized in the APG IV system, a modern classification system for flowering plants, and includes several well-known and economically important families such as the Poaceae (grass family), Arecaceae (palm family), and Commelinaceae (the family that includes the spiderwort and its relatives).

Characteristics

Commelinids share several morphological and biochemical characteristics. Morphologically, many commelinids have stomata that are more or less parallel to the leaf axis, which is a feature not universally present in monocots. Biochemically, they are distinguished by the presence of UV-fluorescent ferulic acid in the cell walls of most members of this group, a feature that can be used as a diagnostic tool.

Classification

The classification of commelinids has undergone significant changes with the advent of molecular phylogenetic studies. According to the APG IV system, the commelinids are divided into several orders, including:

• Arecales
• Commelinales
• Poales
• Zingiberales

These orders encompass a wide range of plants, from the economically vital rice, wheat, and corn of the Poales to the ornamental gingers of the Zingiberales.

Economic Importance

Commelinids are of immense economic importance. The Poaceae family, which is part of the Poales order, includes the cereals that are staple foods for a large portion of the world's population. The Arecaceae family provides essential resources such as coconut, dates, and oil palm. Additionally, many commelinids are used in horticulture, medicine, and as ornamental plants.

Evolution and Distribution

The commelinids are thought to have originated in the late Cretaceous period, with their rapid diversification occurring due to the evolutionary innovations that allowed them to exploit various ecological niches. They are distributed globally, from the tropics to temperate zones, reflecting their adaptability to a wide range of environments.

Conservation

With their wide distribution and economic importance, many commelinids are subject to conservation efforts. Habitat destruction, climate change, and overexploitation are threats to several species within this group. Conservation strategies are being implemented to ensure the sustainability of these vital resources.