Drought rhizogenesis is an adaptive root response to drought stress. New emerging roots are short, swollen, and hairless, capable of retaining turgor pressure and resistant to prolonged desiccation. Upon rewatering, they are capable of quickly forming an absorbing root surface and hair growth. This
rhizogenesis has been called a
drought tolerance strategy for after-stress recovery.
Structural features
These drought induced short roots can be found on either both the
tap root
A taproot is a large, central, and dominant root from which other roots sprout laterally. Typically a taproot is somewhat straight and very thick, is tapering in shape, and grows directly downward. In some plants, such as the carrot, the taproot ...
and
lateral root
Lateral roots, emerging from the pericycle (meristematic tissue), extend horizontally from the primary root (radicle) and over time makeup the iconic branching pattern of root systems. They contribute to anchoring the plant securely into the soil ...
s or on lateral roots only. These patterns are mostly likely a reflection of the plants' individual ability to maintain
meristem
In cell biology, the meristem is a structure composed of specialized tissue found in plants, consisting of stem cells, known as meristematic cells, which are undifferentiated cells capable of continuous cellular division. These meristematic c ...
atic activity under low water potential.
This morphological phenomenon was found in some families of
Angiosperm
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed within a fruit ...
dicot
The dicotyledons, also known as dicots (or, more rarely, dicotyls), are one of the two groups into which all the flowering plants (angiosperms) were formerly divided. The name refers to one of the typical characteristics of the group: namely, ...
perennial
In horticulture, the term perennial ('' per-'' + '' -ennial'', "through the year") is used to differentiate a plant from shorter-lived annuals and biennials. It has thus been defined as a plant that lives more than 2 years. The term is also ...
s and has been documented in Arabidopsis thaliana.
[Vartanian, N., L. Marcotte, and J. Giraudat (1994), Drought Rhizogenesis in Arabidopsis thaliana. Differential responses of hormonal mutants, Plant Physiology, 104, 761-767. Available online: http://www.plantphysiol.org/content/104/2/761.full.pdf]
References
Drought-tolerant plants
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