Delaying Floral Senescence: Molecular Mechanisms and Ethylene Regulation

Abstract

Floral senescence the natural process leading to the decline and eventual death of flowers is a major factor influencing flower shelf-life and aesthetic value, especially within the floriculture sector where postharvest longevity holds economic importance. This review highlights current progress in deciphering the molecular pathways and hormonal signals that regulate this aging process, with a specific focus on ethylene. Ethylene, a central plant hormone, serves as a key modulator of floral aging by activating intricate signaling cascades and gene expression networks. It influences numerous transcription factors, notably the Ethylene Response Factors (ERFs), and modulates the activity of senescence-associated genes (SAGs), thereby accelerating the senescence process in flowers that are responsive to ethylene. This review provides a detailed examination of the physiological and molecular changes occurring during floral senescence, focusing on ethylene's effects on gene regulation, transcription factors such as RhWRKY33, and other key components of senescence pathways. The review further explores the genetic regulation of floral senescence, highlighting ethylene’s interaction with other plant hormones like auxin, cytokinins, polyamines, and abscisic acid. Recent research on gene regulation mechanisms and signaling pathways is discussed, alongside technological advancements like ethylene inhibitors and genetic engineering approaches aimed at mitigating floral senescence. The implications of ethylene’s role in gene regulation and its interaction with other phytohormones are examined in depth. We also analyze the feasibility of applying ethylene-related technologies from both an economic and practical perspective, including a comparison of hormone treatment costs and their impact on flower pricing and longevity in the floriculture market. Despite the focus on ethylene, other environmental and hormonal factors such as climate conditions, macronutrients, and ecosystem influences are also considered in relation to their simultaneous impact on floral senescence. This review concludes by offering future research directions to address existing gaps in our understanding and provide potential solutions for enhancing flower quality, longevity, and productivity.