The root–fungus interface as an indicator of symbiont interaction in ectomycorrhizae

Seedlings of Alnuscrispa (Ait.) Pursh, Alnusrubra Bong., Eucalyptuspilularis Sm., and Betulaalleghaniensis Britt. were grown in plastic pouches and subsequently inoculated with Alpovadiplophloeus (Zeller & Dodge) Trappe & Smith (two different strains), Pisolithustinctorius (Pers.) Coker & Couch, and Laccariabicolor (R. Mre) Orton, respectively, to form ectomycorrhizae insitu. Alnus seedlings were inoculated with Frankia prior to inoculation with the mycosymbiont. The interface established between A. crispa and A. diplophloeus was complex, involving wall ingrowth formation in root epidermal cells and infoldings in Hartig net hyphae. Alnusrubra – A. diplophloeus ectomycorrhizae had an interface lacking epidermal cell wall ingrowths but with infoldings in Hartig net hyphae. The interface between E. pilularis –. tinctorius consisted of branching Hartig net hyphae between radially enlarged epidermal cells lacking wall ingrowths. Ectomycorrhizae between B. alleghaniensis and L. bicolor developed unique interfaces with radially enlarged epidermal cells near the apical meristem, which synthesized dense vacuolar deposits. Very fine branchings occurred in Hartig net hyphae.

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The ultrastructure of the Spilocaea state of Venturia inaequalis in vivo

Canadian Journal of Microbiology ◽

10.1139/m76-166 ◽

1976 ◽

Vol 22 (8) ◽

pp. 1144-1152 ◽

Cited By ~ 9

Author(s):

Michael Corlett ◽

James Chong ◽

E. G. Kokko

Keyword(s):

Cell Wall ◽

Epidermal Cell ◽

Venturia Inaequalis ◽

Conidiogenous Cell ◽

Epidermal Cells ◽

Apical Region ◽

Mesophyll Cells ◽

Epidermal Cell Wall ◽

Primary Conidium

There are indications that the fungus enzymatically degrades the cuticle and epidermal cell wall. The epidermal cells and to a lesser degree the palisade mesophyll cells beneath a sporulating lesion (susceptible reaction) are killed or seriously disrupted. Various stages of conidiogenesis, including development of the primary conidium, were observed. A conidium is delimited by a two-layered transverse septum. Before conidium secession, a new two-layered inner wall is laid down around the entire conidiogenous cell adjacent to the plasmalemma. The apical region of the new inner wall proliferates beyond the annellation scar left by the seceded conidium and eventually produces another conidium.

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Light and electron microscopy of the spermogonial stage of Gymnoconia peckiana, one of the causes of orange rust of Rubus

Botany ◽

10.1139/b08-011 ◽

2008 ◽

Vol 86 (5) ◽

pp. 533-538 ◽

Cited By ~ 1

Author(s):

Charles W. Mims ◽

Elizabeth A. Richardson

Keyword(s):

Cell Wall ◽

Epidermal Cell ◽

Leaf Surface ◽

Light And Electron Microscopy ◽

Epidermal Cells ◽

Wall Material ◽

Cell Wall Material ◽

Leaf Epidermis ◽

Single Nucleus ◽

Epidermal Cell Wall

Hyphae of Gymnoconia peckiana (Howe in Peck) Trotter spread from infected Rubus argutus Link. stems into leaf primordia where they proliferated in an intercellular fashion as leaves differentiated. Hyphae were septate, and each compartment appeared to contain a single nucleus. Hyphae gave rise to numerous haustoria that resembled the monokaryotic haustoria of other rust fungi. Hyphae located immediately adjacent to the upper and lower leaf epidermis gave rise to spermogonial initials. Each initial consisted of a small group of tightly packed hyphae that developed in an intercellular space adjacent to the epidermis. As an initial enlarged, the proliferating hyphae pushed their way between, as well as into, epidermal cells. Invaded epidermal cells soon died. A layer of spermatiophores then developed within each young spermogonium and appeared to push the epidermal cell wall material and leaf cuticle covering the spermogonium out from the leaf surface. Once mature, spermatiophores gave rise to a succession of uninucleate spermatia that emerged from the tip of each spermatiophore. Spermatia initially accumulated beneath the layer of epidermal cell wall material and cuticle that covered the developing spermogonium and appeared to push this layer further out from the leaf surface until it ruptured. A few receptive hyphae were observed in mature spermogonia.

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Development of Colletotrichum trifolii races 1 and 2 on alfalfa clones resistant and susceptible to anthracnose

Canadian Journal of Botany ◽

10.1139/b88-011 ◽

1988 ◽

Vol 66 (1) ◽

pp. 75-81 ◽

Cited By ~ 9

Author(s):

A. C. L. Churchill ◽

C. J. Baker ◽

N. R. O'Neill ◽

J. H. Elgin Jr.

Keyword(s):

Cell Wall ◽

Epidermal Cell ◽

Pore Formation ◽

Epidermal Cells ◽

Germ Pore ◽

Colletotrichum Trifolii ◽

Direct Penetration ◽

Race 1 ◽

Epidermal Cell Wall ◽

Race 2

Resistant and susceptible alfalfa clones derived from the cultivar Arc were spray inoculated with conidia from race 1 or race 2 isolates of Colletotrichum trifolii Bain in compatible and incompatible combinations. No significant differences were found in the frequencies of formation of immature or mature appressoria or in germ-pore formation by either race of C. trifolii on resistant or susceptible plants. These results indicate that incompatibility is not associated with the failure of conidia to germinate or to form appressoria with germ pores. In a small number of observations, penetration pegs were observed in tissue of both resistant and susceptible plants. Colletotrichum trifolii initiated infections in alfalfa by direct penetration of the epidermis via a penetration peg from the appressorium. Although the fungus spread rapidly throughout susceptible hosts, we observed fungus penetration only of epidermal cells of resistant hosts. Therefore, it appears that expression of alfalfa resistance to C. trifolii occurs near the time of epidermal cell wall penetration.

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A histological and histochemical comparison of the mucilages on the root tips of several grasses

Canadian Journal of Botany ◽

10.1139/b80-300 ◽

1980 ◽

Vol 58 (24) ◽

pp. 2581-2593 ◽

Cited By ~ 43

Author(s):

N. K. Miki ◽

K. J. Clarke ◽

M. E. McCully

Keyword(s):

Cell Wall ◽

Epidermal Cell ◽

Outer Layer ◽

Epidermal Cells ◽

Root Cap ◽

Carboxyl Groups ◽

Root Tips ◽

Sudan Grass ◽

Epidermal Cell Wall ◽

Inner Region

Young, axenically grown roots of grasses are covered by two types of mucilage. Gelatinous material originates from the root cap, and a firm, uniformly thick mucilage overlies the columnar epidermal cells. Histochemical properties of these mucilages are similar in corn, wheat, barley, oats, sorghum, and a Sudan grass – sorghum hybrid.The epidermal mucilage has a thin outer and a thicker inner layer distinct from the epidermal cell wall. Both mucilage layers are strongly autofluorescent, birefringent, and PAS positive. Reactions of the outer layer and cell wall indicate carboxyl groups. These are absent from the inner mucilage. Root cap mucilage has a inner region with histochemical properties resembling those of the inner epidermal mucilage. The outer portion of the root cap mucilage is not fluorescent, not birefringent, weakly PAS positive, and carboxylated.

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Cellulose intrafibrillar mineralization of biological silica in a rice plant

Scientific Reports ◽

10.1038/s41598-021-87144-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Eri Nakamura ◽

Noriaki Ozaki ◽

Yuya Oaki ◽

Hiroaki Imai

Keyword(s):

Cell Wall ◽

Silica Nanoparticles ◽

Epidermal Cell ◽

Rice Plant ◽

Cellulose Nanofibers ◽

Rice Husks ◽

Vital Activity ◽

Mineralization Process ◽

Shape Controlled ◽

Epidermal Cell Wall

AbstractThe essence of morphological design has been a fascinating scientific problem with regard to understanding biological mineralization. Particularly shaped amorphous silicas (plant opals) play an important role in the vital activity in rice plants. Although various organic matters are associated with silica accumulation, their detailed functions in the shape-controlled mineralization process have not been sufficiently clarified. In the present study, cellulose nanofibers (CNFs) were found to be essential as a scaffold for silica accumulation in rice husks and leaf blades. Prior to silicification, CNFs ~ 10 nm wide are sparsely stacked in a space between the epidermal cell wall and the cuticle layer. Silica nanoparticles 20–50 nm in diameter are then deposited in the framework of the CNFs. The shape-controlled plant opals are formed through the intrafibrillar mineralization of silica nanoparticles on the CNF scaffold.

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THE STRUCTURE OF THE PRIMARY EPIDERMAL CELL WALL OF AVENA COLEOPTILES

The Journal of Cell Biology ◽

10.1083/jcb.3.2.171 ◽

1957 ◽

Vol 3 (2) ◽

pp. 171-182 ◽

Cited By ~ 20

Author(s):

S. T. Bayley ◽

J. R. Colvin ◽

F. P. Cooper ◽

Cecily A. Martin-Smith

Keyword(s):

Cell Wall ◽

Outer Wall ◽

Epidermal Cells ◽

Cellulose Microfibrils ◽

X Rays ◽

Primary Wall ◽

Normal Type ◽

Number Of Layers ◽

Angle Scattering ◽

Epidermal Cell Wall

The primary walls of epidermal cells in Avena coleoptiles ranging in length from 2 to 40 mm. have been studied in the electron and polarizing microscopes and by the low-angle scattering of x-rays. The outer walls of these cells are composed of multiple layers of cellulose microfibrils oriented longitudinally; initially the number of layers is between 10 and 15 but this increases to about 25 in older tissue. Where epidermal cells touch, these multiple layers fuse gradually into a primary wall of the normal type between cells. In these radial walls, the microfibrils are oriented transversely. Possible mechanisms for the growth of the multilayered outer wall during cell elongation are discussed.

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Cell wall structural changes lead to separation and shedding of biofouled epidermal cell wall layers by the brown alga Ascophyllum nodosum

PROTOPLASMA ◽

10.1007/s00709-020-01502-3 ◽

2020 ◽

Vol 257 (5) ◽

pp. 1319-1331 ◽

Cited By ~ 2

Author(s):

Laryssa Halat ◽

Moira E. Galway ◽

David J. Garbary

Keyword(s):

Cell Wall ◽

Epidermal Cell ◽

Brown Alga ◽

Structural Changes ◽

Ascophyllum Nodosum ◽

Epidermal Cell Wall

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Structure and ontogeny of Alnus crispa – Alpova diplophloeus ectomycorrhizae

Canadian Journal of Botany ◽

10.1139/b86-026 ◽

1986 ◽

Vol 64 (1) ◽

pp. 177-192 ◽

Cited By ~ 48

Author(s):

H. B. Massicotte ◽

R. L. Peterson ◽

C. A. Ackerley ◽

Y. Piché

Keyword(s):

Structural Changes ◽

Hyphal Growth ◽

Root Surface ◽

Epidermal Cells ◽

Transfer Cells ◽

Wall Ingrowths ◽

Alnus Crispa ◽

Hartig Net ◽

Fungal Hyphae ◽

Branching System

Alnus crispa (Ait.) Pursh seedlings were grown in plastic pouches and inoculated with Frankia to induce nodules and subsequently with Alpova diplophloeus (Zeller & Dodge) Trappe & Smith to form ectomycorrhizae. The earliest events in ectomycorrhiza formation involved contact of the root surface by hyphae, hyphal proliferation to form a thin mantle, and further hyphal growth to form a thick mantle. Structural changes in the host, the mycosymbiont, and the fungus–epidermis interface were described at various stages in the ontogeny of ectomycorrhizae. Fungal hyphae in contact with epidermal cells in the regions of intercellular penetration and paraepidermal Hartig net developed numerous rough endoplastic reticulum cisternae. In more proximal regions of the mycorrhiza, these gradually became fewer in number and smooth. A complicated labyrinthine wall branching system also developed in the fungus in these regions. Concurrently, epidermal cells formed wall ingrowths in regions adjacent to Hartig net hyphae. There was a gradient in the formation of these epidermal transfer cells as the mycorrhiza developed, and an additional deposition of secondary cell wall over the wall ingrowths occurred as transfer cells senesced. Nonmycorrhizal control roots did not develop epidermal wall ingrowths. Electron-dense material, which was also autofluorescent, was deposited in the outer tangential walls of the exodermis contiguous to the paraepidermal Hartig net.

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