Natural plant growth regulators mechanisms

Plant growth regulators, whether natural occurring or synthetic have been used commercially since the 1950 s. Their uses have generally been to modify growth, enhance yields of food and fiber, adapt plants to scheduled harvest patterns and make certain crops more adaptable to mechanical harvesting. 

Investigations of the role that these natural products play in the metabolism of the plants where they are produced and the extent to which they control growth and developmental processes appear of interest. Also, the nature of the control mechanisms and their efficacy for herbicidal activity may warrant investigation. The recent interest in brassinosteroids as plant growth regulators may also lead to an application for weed control (31). 

Possible Mechanism of Allelopathlc Action of Water-Insoluble Plant Lipids. Many non-polar natural products with germination and growth regulation activities In laboratory tests are In pure form not sufficiently water soluble to account for their allelopathlc activities observed In the field. For this reason the notion exists that sterols and other non-polar plant constituents are not likely to play a role In allelopathlc actions, and It Is generally concluded that the bioactivity data observed In the laboratory are therefore coincidental. 

When one observes that a certain secondary plant product exerts a growth-regulating activity, obviously the first question that concerns the physiologist is its mode of action. From the foregoing discussion, we know that several diversified organic compounds exhibit different growth phenomena in isolated or intact plant systems. But it is difficult to discuss the mechanism of action of these natural products because of ... 

Beever JE, Woolhouse HW (1973) Increased cytokinin from root system of Perilla and flower and fruit development. Nature 246 31-32 Beever JE, Woolhouse HW (1974) Increased eytokinin export from the roots of Perilla frutescens following disbudding or floral induction. In Bieleski RL, Ferguson AR, Cresswell MM (eds) Mechanism of regulation of plant growth. Roy Soc N Z, Wellington, pp 681-686... 

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