Genetic Control of Storage Root Development

The formation of plants' storage organs, in particular the storage root, is an example of plants’ specialization in the accumulation of substances. Studying the genetic mechanisms for the development of the storage root is very relevant in connection with the economic importance of root crops. Nevertheless, the genetic control of storage root’s development is currently poorly studied. The major volume of dicotyledonous plants' storage root is usually occupied by highly parenchymatous secondary conducting tissues (phloem and/or xylem), which are formed as a result of proliferation of cambium cells and are specialized in the accumulation of nutrients. Currently, a number of regulators of cambium development have been identified. The WOX-CLAVATA system (including the CLE signal peptides, their receptors, and their targets: homeodomain-containing WOX transcription factors), as well as transcription factors of other families and phytohormones, control the activity of the cambium meristem. The review presents up-to-date data on the mechanisms of cambium activity’s regulation, differentiation of conductive tissues and nutrient storage, and data on conservative and specific regulators of the development of storage roots in the best studied root crops: radishes, turnips, beets, carrots, sweet potatoes, and cassava.