TDZ Induced Diverse In Vitro Responses in Some Economically Important Plants

Abstract

A fleeting look at the diverse responses exhibited by a variety of plants against a urea derived, multifunctional plant growth regulator thidiazuron (N-phenyl-N′-1,2,3-thidiazol-5-ylurea (TDZ)) reveals its significance in plant tissue culture. Few decades ago this substituted phenylurea compound was in use rarely for inducing tissue culture responses in woody plant species, but later became one of the most sought-after plant growth regulators for induction of in vitro responses even in non-woody plant species. One notable feature of this growth regulator is its cytokinin- and auxin-type responses reported in excised tissues of plants, which is otherwise familiar as a defoliant for the mechanical harvest of cotton bolls. Often morphogenetic responses such as organogenesis via direct or indirect way, somatic embryogenesis, callus cell culture proliferations, etc. and physiological changes at cellular level were demonstrated upon administering TDZ in vitro. Various biochemical core mechanisms for such triggered responses of TDZ have been reviewed. Under this context, a glance at TDZ induced in vitro responses in a woody plant species, such as coffee, vanilla orchid, annatto dye-yielding tropical plant Bixa orellana, banana, a natural non-calorie sweetener Stevia rebaudiana and natural flavour 2H4MB producing Decalepis hamiltonii, will evoke interest among researchers in this area, as the outcome facilitates further advances in this area and also helpful for better utilization of TDZ for biotechnological improvement of economically important plant species.