Olmones

Olmones were a hypothesized class of chemical messenger molecules proposed to act within plants. The concept was introduced to explain observed communication and coordination between different parts of a plant that could not be fully accounted for by the known plant hormones (such as auxins, cytokinins, gibberellins, abscisic acid, and ethylene). The term "olmone" was coined to suggest a regulatory substance distinct from, but related to, hormones.

The central idea behind olmones was that they are released by a plant organ in response to a localized stress or stimulus, and then transported to other parts of the plant, triggering a systemic response. Unlike hormones, which generally have broad developmental effects and are involved in long-term growth regulation, olmones were envisioned as being primarily involved in rapid, short-term responses to environmental challenges such as herbivore attack, pathogen infection, or changes in environmental conditions.

Research into plant signaling has identified a number of compounds that fulfill aspects of the proposed olmone role. Examples include systemin, jasmonates, and certain volatile organic compounds (VOCs). These compounds are produced in response to stress and can trigger defense responses in distant parts of the plant, making them good candidates for fulfilling the olmone concept.

While the term "olmone" is not as widely used in modern plant physiology as it once was, the concept it represented has been highly influential in shaping our understanding of systemic plant signaling and the complex interplay of chemical messengers that allow plants to respond effectively to their environment. The discovery and characterization of compounds like systemin and jasmonic acid pathways demonstrated the validity of the olmone hypothesis, even if the original proposed definition has been nuanced and refined over time. Modern research continues to identify new signaling molecules and pathways that contribute to the intricate communication networks within plants.