A survey of angiosperm species to detect hypodermal Casparian bands. I. Roots with a uniseriate hypodermis and epidermis

Abstract

PERUMALLA, C. J., PETERSON, C. A. & ENSTONE, D. E., 1990. A survey of angiosperm species to detect hypodermal Casparian bands. I. Roots with a uniseriate hypodermis and epidermis. Roots of 181 species from 53 families were surveyed to determine the frequency of Casparian bands in hypodermal layers. For six species, inconclusive data were obtained. The roots of the remaining 175 species were divided into three categories on the basis of this survey. In the first, a hypodermis is absent (12 species): no wall modifications were observed in the outer cortex and this region was permeable to the apoplastic dye Cellufluor. In the second, a hypodermis is present, but a hypodermal Casparian band is absent (seven species). In roots of six species, no wall modifications were detected in the hypodermis; the one remaining species had lignified phi thickenings which were permeable to Cellufluor. In the third, both a hypodermis and a hypodermal Casparian band are present (156 species). These Casparian bands consisted of suberin deposits throughout the width of the anticlinal walls of the hypodermis. The tangential walls of the hypodermis were also suberized, indicating that suberin lamellae were probably also present. Hypodermal Casparian bands were found in roots of hydrophytic, mesophytic and xerophytic species and in members of primitive as well as advanced families. The widespread occurrence of these bands (in 89% of the species surveyed) suggests that they were present in the type ancestral to the flowering plants and that this feature has been retained by many species in this group. The epidermal cell walls of the majority of species examined were suberized but were permeable to Cellufluor.

Anatomical Development of Cell Structure Including Casparian Strip during Root Growth in Grapevines

“…The exodermis, as with the endodermis, also develops the characteristics of an apoplastic barrier. In the fibrous roots of grapevines, the epidermis is a transient cell layer and the hypodermis develops lignosuberized Casparian bands (Perumalla et al, 1990); however, in the present study, the Casparian strip could not clearly be detected in the exodermis.…”

Development of Casparian strip in rice cultivars

“…The main function of CSs is to inhibit water and salt transport into the stele by blocking nonselective apoplastic bypass in the root. 3 In general, an exodermis is present in most angiosperm roots, 1,25 whereas an endodermis is present in all roots so far examined, except for some members of the Lycopodiaceae. 26,27 In roots of most species, the endodermis starts to mature before the exodermis, but the sequence of development is roughly the same in cells of both layers.…”

“…The development of Casparian strips (CSs) in the root endo-and exodermis is one such strategy. [1][2][3] In roots of most species, the sequence of development of the endo-and exodermis is roughly the same and involves two consecutive developmental stages: (1) formation of CSs in radial and transverse walls impregnating the primary cell wall pores with lipophilic and aromatic substances and (2) deposition of suberin lamellae to the inner surface of anticlinal and tangential cell walls. [4][5][6] A major function of the CS is to block the non-selective apoplastic bypass flow of water and ions into the stele.…”

Effects of exposure to humid air on epidermal viability and suberin deposition in maize (Zea mays L.) roots

“…Casparian bands in the endodermis are a consistent feature of vascular plants, but the later development of suberin lamellae in this layer, and of both Casparian bands and suberin lamellae in the exodermis, are more variable with species (Kroemer 1903;Perumalla, Peterson & Enstone 1990; and, in some cases, with the environment. The present study is concerned with the endodermis and exodermis of maize (Zea mays L.), in which the exodermis is classed as uniseriate and uniform.…”