Role of Ethylene in Plant Tissue Culture.

Ethylene affects in-vitro plant morphogenesis in many ways, depending upon species, genotypes, and developmental stages. It can stimulate or inhibit the development, and a minute change in concentration could lead either the successful regeneration or failure. Studies in different plant taxa such as Datura, barley, coffee, Arabidopsis, tomato, and pepper show that the fine-tuning of ethylene levels could enhance embryogenesis, shoot organogenesis, whereas, changes in these optimum concentrations could lead to stunted morphogenesis. Adding ACC or Ethephon increases ethylene level, whereas silver salts or cobalt chloride diminish its synthesis or reception, showing its regulatory feature. Genetic studies depend on ethylene-insensitive mutants, ethylene-overproducing mutants, and transgenic lines altering ACC synthase or ACC oxidase. These studies reveal that ethylene works with auxins, cytokinins, and polyamine to lead developmental switches during morphogenesis. The tissue and developmental stage further shape ethylene action, callus induction, embryo maturation, and shoot regeneration each demand distinct ethylene levels. Combining ethylene management with molecular, physiological, and epigenetic approaches, could help regeneration challenges in difficult Capsicum species. Taken together, literature positions ethylene as a pivotal, context-dependent regulator of plant tissue culture morphogenesis.