Triacontanol as a Plant Growth Regulator

Abstract

Abstract Triacontanol (TRIA) is synthesized by plants and is a component of most biological material. New formulations of TRIA have shown activity with femtomolar doses. Although the majority of TRIA in plants is bound to (and is located in) the cuticle, small amounts can be found in parenchyma tissue. Exogenous applications of TRIA regulate directly or indirectly several physiological and biochemical processes. Many studies have shown that TRIA can increase the yield of crops, but the results have not been sufficiently consistent in the United States to recommend its use commercially. Several experiments suggest that TRIA, a metabolite of TRIA, or a secondary messenger, moves rapidly in plants after initial application. Changes in the levels of several metabolites and the optimum environmental conditions for treatment indicate that carbohydrate metabolism may be involved in the plants’ response to TRIA. Additionally, several enzymes relating to carbohydrate metabolism increase in activity following TRIA treatment. Warm temperatures before foliar applications improved the plants response to TRIA. Many compounds have an antagonistic effect on the response of plants to TRIA. The most significant are phthalate esters, which commonly occur in water and the research environment. This contamination may explain the inconsistent results encountered by several researchers in the laboratory and field. TRIA has elicited many growth responses in plants with a rapidity not shown for other plant hormones or growth regulators.