Root flavonoids

The plasma membrane strength of the root-tip cells and root phenolic compounds are correiated with Al tolerance in several common woody plants

“…Considering the concentrations of phenolic compounds in the cytoplasm and the stronger binding affinity to Al ions, phenolic compounds could act as effective detoxifiers of Al ions in the cytoplasm before the formation of [Al(H_ 1 Cit)] -1, [A1 3 (H_ 1 CitMOH)]4-, and [AlCit 2 P- (Harris et al 1997) or [A13(OH)4Cit3]4-and/or [Al(OH)(H_ 1 Cit)J2- (Ohman and Sjoberg 1988) at pH 7.0 which have higher stability constants than the Al-ATP complex (10.9;Ma 2000). Phenolic compounds in roots playa significant role in protecting the plants from pests and diseases, exerting allelopathic effects, and being an essential source of pharmaceuticals (Rao 1990). The contents of phenolic compounds have also been widely known to increase by nutrient deficiencies such as N (Chishaki and Horiguchi 1997) and P, K, and S (Gershenzon 1983), and are metabolized as intermediates for the synthesis of lignin which is abundant in woody plants.…”

“…Phenolic compounds have several important functions and are widely distributed in plants (Rao 1990). Some phenolic compounds have been reported to be capable of binding with Al ions due to their relatively higher association constants when compared with organic acids even under acidic conditions (Tam and McColl 1990).…”

Potencial alelopático de plantas de acapu (Vouacapoua americana): efeitos sobre plantas daninhas de pastagens

“…Aparentemente, todas as partes das plantas podem conter substâncias alelopáticas. As informações disponíveis mostram que as substâncias químicas com atividades alelopá-ticas não se distribuem uniformemente nos diversos órgãos das plantas, podendo a maior concentração estar tanto nas folhas como nas raízes ou cascas do tronco de espécies arbóreas (Souza Filho et al, 1997;Corcera et al, 1992;Heisey, 1990;Rao, 1990;Friedman & Waller, 1983). Em diferentes bioensaios, essas Concentração do extrato (%) Comprimento da radícula (cm)…”

The Effect Of Some Plant Growth Regulators And Their Combination With Methyl Jasmonate On Anthocyanin Formation In Roots Of Kalanchoe Blossfeldiana

“…Rao (1990) suggests that root flavonoids play significant roles in regulating root growth and functions, influencing different aspects of nitrogen cycle and protecting the plants against diseases.…”

“…Lightdependent anthocyanin synthesis has been extensively used as a model system for studies of the mechanism of photoregulation of plant development (Mancinelli 1985). Light can penetrate the soil and influence not only root growth, but also several soil microbiological and biochemical processes (Rao 1990). Anthocyanins in the roots may act as a protective antioxidant against stress factors from the environment.…”