A clue to the relative health of plants and the types of abiotic stresses (environmental not biological) can be observed in the ratio of the above ground parts and the root system and the architecture of the root systems. The study of Plant Stress Dynamics is at the heart of a grower’s understanding of production methods, especially in biological production or where ideal growing conditions cannot be provided. This paper reviews recent scientific literature on root development and the performance of root systems in horticultural plants exposed to abiotic stress. When root systems are under abiotic stresses, there is usually a redistribution of nutrients from shoot to root system causing a reduction in the shoot to root ratio; above ground parts may appear stunted. Conversely, reductions in light or excess nutrients usually cause an increased shoot to root ratio, a poorer reduced root system. Root architecture can also provide a clue to the stresses to which a plant is responding. Stresses that inhibit root growth often cause roots to grow shorter with more branches. In low moisture or increased CO2 concentrations, plants tend to develop a more extensive root system, working harder to obtain the limited moisture. Substances that regulate growth and development in root systems include: abscisic acid (ABA), ethylene, reactive molecules containing oxygen or nitrogen.
“Root development in horticultural plants grown under abiotic stress conditions – a review”, J.A.Franco, S.Bañón, M.J.Vicente, J.Miralles, J.J.Martínez-Sánchez. Journal of Plant Science and Biotechnology, Vol.86 No.6, pp 543-556 Further information, Fax: 0044 1382 561412, E-mail: jhsb@hutton.ac.uk, www.jhortscib.org/Vol86/86_6/1.htm |
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