Suberized endodermis

An endodermis, wavy in character and composed of endodermal cells whose brownish walls are strongly suberized. 

Stress seems to affect suberization. Salt stress due to mineral deficiencies can result in changes in suberization. For example, magnesium deficiency caused the hypodermis (Fig. 6.4.3) and endodermis of Zea mays roots to have more heavily suberized cell walls (372), whereas iron deficiency in Phaseolus vulgaris led to a drastic decrease in suberin deposition in the roots (412). Mechanical stress in the form of physical impedance to root growth caused increased suberization in the walls of endodermal cells of Hordeum vulgare roots (497). 

Suberin is laid down in various internal locations in order to seal off specific regions of the plant (234). In the primary development of plant roots, suberin is deposited in the Casparian band of endodermal cells (45, 103, 162, 317, 364, 367, 369, 474, 483). The presence of suberin in the Casparian band of the endodermis of Sorghum bicolor was shown chemically by depolymerization (244). Suberized layers are also found in the mestome sheath and bundle sheath cell walls of grasses (52, 61, 108, 118, 171, 172, 331, 368), and these layers have been chemically characterized in Zea mays and Secale cereale (114, 146). 

Pozuelo J M, Espelie K E, Kolattukudy P E 1984 Magnesium deficiency results in increased suberization in endodermis and hypodermis of corn roots. Plant Physiol 74 256-260... 

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