Mediators, Genes and Signaling in Adventitious Rooting

Abstract

Adventitious roots are a post-embryonic root which arise from the stem and leaves and from non-pericycle tissues in old roots and it is one of the most important ways of vegetative propagation in plants. Many exogenous and endogenous factors regulate the formation of adventitious roots, such as Ca 2+ , sugars, auxin, polyamines, ethylene, nitric oxide, hydrogen peroxide, carbon monoxide, cGMP, MAPKs and peroxidase, etc. These mediators are thought to function as signaling and mediate auxin signal transduction during the formation of adventitious roots. To date, only a few genes have been identified that are associated with the general process of adventitious rooting, such as ARL1, VvPRP1, VvPRP2, HRGPnt3, LRP1 and RML, etc. Auxin has been shown to be intimately involved in the process of adventitious rooting and function as crucial role in adventitious rooting. Great progress has been made in elucidating the auxin-induced genes and auxin signaling pathway, especially in auxin response Aux/IAA and ARF genes family and the auxin receptor TIR1. Although, some of important aspects of adventitious rooting signaling have been revealed, the intricate signaling network remains poorly understood.

VEGETATIVE RESCUE AND CUTTINGS PROPAGATION OF Araucaria angustifolia (Bertol.) Kuntze

“…Propagule rooting is influenced by endogenous and exogenous factors, such as ontogenetic and physiological state, propagule type, humidity, temperature, light incidence, substrate, nutritional and hormonal balance, as well as certain genes and enzyme activity (BASAK et al, 2000;LI et al, 2009;PIJUT et al, 2011). Nevertheless, the probability of successful rooting can be enhanced with growth regulators, such as auxins.…”

Auxin Control in the Formation of Adventitious Roots

“…Adventitious roots can arise naturally from stem tissue under stressful environmental conditions; they may also be induced by mechanical damage or following tissue culture regeneration of shoots (Li et al, 2009). They are postembryonic roots which arise from the stem and leaves and from nonpericycle tissues in old roots (Geiss et al, 2009).…”

Adventitious rooting of conifers: influence of physical and chemical factors

“…These roots may form naturally from stem tissue or may be induced by stressful environmental conditions, by mechanical damage or following tissue culture regeneration of shoots (Li et al 2009). Adventitious root formation (ARF) is a critical step in vegetative propagation.…”

“…The initiation phase is characterized by cell divisions and root primordia organization. The expression phase is characterized by intra-stem growth of root primordia and root emergence (Li et al 2009). The chemical and physical factors that affect rooting include plant growth regulators (PGRs) (Wiesman et al 1989;Davis and Haissig 1990), nutrients (the carbohydrate source foremost) (Wiesman and Lavee 1995), temperature and light (Haissig 1990;Corrêa and Fett-Neto 2004).…”