Flow of cytokinins through the environment

Cytokinins are a group of plant growth regulators that elicit a wide range of physiological responses in plants. Cytokinins are not restricted to plants alone but also occur in lower order plants, algae and bacteria as well as in parasitic insects and nematodes. The use of cytokinins, including synthetic cytokinins, in agriculture also contributes to the available cytokinin pool. This review discusses possible ways in which cytokinins move through the environment such as via root exudates, leaf litter and in water systems, thus potentially influencing the growth and development of plants and other organisms. This review highlights the need for a more holistic and ecological approach in order to understand cytokinin regulation and homeostasis in plants.