Plant Growth Retardants and Phosphorus Metabolism

Abstract

The term 'growth retardant' is used for all chemicals that slow cell division and cell elongation in shoot tissues and regulate plant height physiologically without formative effects (Cathey, 1964). Groups of growth retardants include quaternary ammonium carbamates (Halevy and Cathey, 1960) and phosphonium compounds (Preston and Link, 1958). Two of the most widely used growth retardants are (2-chloroethyl) trimethylammonium chloride (Cycocel) and 2,4-dichlorobenzyl tributylphosphonium chloride (Phosfon). Certain growth retardants have been shown to interact with auxin (Kuraishi and Muir, 1963) or with gibherellic acids (Badlev, Lang, and Agatep, 1965). Because the effects of growth retardants are in many aspects opposite to those of gibberellins, they have been designated anti gibberellins. Lockhart (1962), however, suggested that they simply be considered antimetabolites.