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1

Nebija, Flurim, Gjose Stefkov, Marija Karapandzova, Biljana Bauer Petrovska, and Svetlana Kulevanova. "Morphological and anatomical characteristics of the root and herb from Eryngium campestre L. (Apiaceae)." Macedonian Pharmaceutical Bulletin 52 (2006): 57–64. http://dx.doi.org/10.33320/maced.pharm.bull.2006.52.008.

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Research on the morphological and anatomical constitution of the root and herb from the plant Eryngium campestre L., Apiaceae has been done in this work. The follow elements important for the identification of drug have been defined: in leafs thick cuticle, isolateral mesophill with palisade tissue on the upper and lower region of the leaf and much reduced spongy parenchyma; characteristic arrangement of the mechanical collenchyma tissue, especially in leafs, characteristic wrinkles in the leaf cuticle. In the herb's powder the follow elements could be found: trachea fragments with specific ring wrinkles, parts from the epiderma with stomata, druses and knee-shaped mechanical hairs. In the root and the stem characteristic are secretory tubes and the presence of calcium oxalate druses in great quantity. Additionally in the root typical arrangement of tissues characteristic for the secondary root construction could be noticed, with: xylem rays in wood and in a bark, laticifers, periderma on the periphery, characteristic arrangement of the vascular bundles and great number of druses, esspecialy in the wood. In the root powder: trachea fragments with spiral thickenings, fragments of periderm and cork, parts from parenchyma of the bark with druses could been put aside.
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2

Inácio, Vera, Carolina Lobato, José Graça, and Leonor Morais-Cecílio. "Cork cells in cork oak periderms undergo programmed cell death and proanthocyanidin deposition." Tree Physiology 41, no. 9 (February 22, 2021): 1701–13. http://dx.doi.org/10.1093/treephys/tpab031.

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Abstract Vascular plants with secondary growth develop a periderm mostly composed of dead suberized cork cells to face environmental hostile conditions. Cork oak has a highly active and long-living phellogen forming a remarkably thick periderm that is periodically debarked for industrial purposes. This wounding originates the quick formation of a new traumatic periderm, making cork oak an exceptional model to study the first periderm differentiation during normal development in young sprigs and traumatic (wound) periderm formation after debarking. Here, we studied the poorly known first periderm differentiation steps that involve cell wall suberization, polyphenolic accumulation and programmed cell death (PCD) by combining transmission electron microscopy, histochemical and molecular methods in periderms from young sprigs. These processes were further compared with traumatic periderms formed after wounding using molecular and histochemical techniques, such as the polyphenolic accumulation. In the first periderms from young sprigs, four distinct differentiation stages were defined according to the presence of PCD morphological features. First young and traumatic periderms showed an upregulation of genes related to suberin biosynthesis, proanthocyanidins biosynthesis and transport, autophagy, and PCD. Traumatic periderms revealed an overall upregulation of these genes, likely resulting from ontogeny differences and distinct phellogen origin associated with a faster metabolism, highlighting the impact of wounding on phellogen activity after debarking. First periderms from young sprigs showed gradual accumulation of proanthocyanidins in the vacuoles throughout PCD stages until total filled lumens, whereas in traumatic periderms, these compounds were found cell wall linked in already empty cells. This work enabled a comprehensive overview of the cork cells differentiation processes contributing to deepening the knowledge of the fundamental ontogenic program of this protective tissue, which is also a unique forest product, constituting the basis of a sustainable and profitable industry.
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3

O'Gara, E., K. Howard, I. J. Colquhoun, B. Dell, J. McComb, and G. St E. J. Hardy. "The development and characteristics of periderm and rhytidome in Eucalyptus marginata." Australian Journal of Botany 57, no. 3 (2009): 221. http://dx.doi.org/10.1071/bt08225.

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To understand the pathway used by Phytophthora cinnamomi Rands to penetrate the bark of jarrah, the present study describes unwounded periderm and rhytidome development. Periderm formation is described from its initiation in 4-week-old seedlings to the formation of rhytidome in saplings. Periderm in young seedlings consists of a single type of phellem, namely thin-walled suberised cells. In older seedlings where multiple layers of periderm have formed, layers of thick-walled lignified phellem cells in compacted bands alternate with thin-walled suberised cells. Rhytidome formation in older lignotuberous seedlings and in sapling jarrah occurs through the isolation of secondary phloem by periderm. The rhytidome consists of expanded and partially disintegrated secondary phloem tissue sandwiched between layers of phellem cells. Localised periderm formation beneath stomata results in the formation of lenticels, which are ephemeral features. Superficial periderms occur at sites of leaf and shoot abscission, and of lateral shoot emergence. Concealed axillary shoots lack cuticle on emergence. As the trees age, the internal production of lignified and suberised periderm and rhytidome results in an impenetrable barrier to invasion by P. cinnamomi. However, external sites including lenticels and leaf and shoot abscission and emergence areas, all provide points of ingress in unwounded stems.
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4

Bates, Rick M., and Alexander X. Niemiera. "A Comparison of Morphological Features Affecting Water Loss in Norway Maple and Washington Hawthorn Stems." Journal of Environmental Horticulture 14, no. 2 (June 1, 1996): 71–76. http://dx.doi.org/10.24266/0738-2898-14.2.71.

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Abstract Crataegus phaenopyrum (Washington hawthorn) stems are known to be more sensitive to water stress during cold storage than Acer platanoides (Norway maple). Histological examination revealed that maple stems had a highly suberized periderm, and uniform cuticle with few disruptions. Periderm suberization of hawthorn stems was variable and extensive peridermal cracking was evident. Cuticle wax decreased with increasing distance from the stem apex for both species. No differences in lenticellar characteristics were found between species. Results indicated that hawthorn stems had anatomical features that allowed for more water loss than maple stems, which may provide a possible explanation for differences in maple and hawthorn stem water loss rates.
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5

Kitamura, Kunio, Mariko Sezaki, and Masako Yanazawa. "Analysis of Embryonic Chick Periderm by Monoclonal Antibody Specific against Periderm1. (periderm/ectoderm/monoclonal antibody/cytokeratin/chick embryo)." Development, Growth and Differentiation 32, no. 2 (April 1990): 157–63. http://dx.doi.org/10.1111/j.1440-169x.1990.00157.x.

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6

Antonio Alonso, Alexandre, and Silvia Rodrigues Machado. "Stem Protective Tissue in Erythroxylum Tortuosum (Erythroxylaceae), A Fire Tolerant Species from Cerrado." IAWA Journal 29, no. 1 (2008): 69–77. http://dx.doi.org/10.1163/22941932-90000171.

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The origin and structure are described of the secondary protective tissue in the stem of Erythorxylum tortuosum Mart., a fire tolerant shrubby species common in Brazilian cerrado. The highly tortuous stems are covered with thick bark which is more developed at the base of the stem. After fire in the cerrado, rhytidome fragments of the burned stem flake off, revealing newly formed cork. The first periderm appears near of the terminal buds and is iniated by periclinal divisions in subepidermal cells giving rise to radial rows of cells. The first phellogen is discernible only after the differentiation of the several radial rows of cork cells. Other phellogens have their origin in successively deeper layers of the cortex. The sucessive periderms are discontinuous around the circumference. The collapsed cells with phenolic substances and the accumulated dead cells cause the formation of discontinuous blackish lines, which delimit the sucessive periderms in the rhytidome. The rhytidome contains large quantities of sclereids developed from cell wall thickening of cortex cells. The occurrence of periderm in the young parts of the stem and of rhytidome in the older parts represents pyrophytic characteristics and may explain, in part, the fire tolerance of this species.
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7

Decombeix, Anne-Laure, Edith L. Taylor, and Thomas N. Taylor. "BARK ANATOMY OF LATE PERMIAN GLOSSOPTERID TREES FROM ANTARCTICA." IAWA Journal 37, no. 3 (September 7, 2016): 444–58. http://dx.doi.org/10.1163/22941932-20160146.

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The Glossopteridales are an extinct group of seed plants that dominated Gondwanan floras during the Permian. Their remains are found across a wide range of habitats and paleolatitudes, and it is particularly interesting to understand the anatomical characteristics that might have enabled such an extensive distribution. Here, we document for the first time the bark anatomy of high-latitude glossopteridalean trees using peels and thin sections made from a Late Permian trunk from Skaar Ridge, Antarctica. The bark is 3 cm thick. The secondary phloem is composed of sieve cells, axial and ray parenchyma, and fibers arranged in discontinuous unicellular tangential layers. The outer bark is a rhytidome, with numerous alternating layers of periderm and non-conducting secondary phloem showing some proliferation of the axial parenchyma. Successive periderms mostly run parallel to the cambium, with some longitudinal undulation and rare connections between two periderms. A similar anatomy was observed in bark fragments found isolated in the matrix or closely associated with large glossopterid stems or roots. The anatomy of the Skaar Ridge specimens shows that Antarctic Glossopteridales had a relatively thick, probably stringy bark. The retention of a significant amount of insulating dead bark tissue on the trunk likely provided protection of the cambium, conducting secondary phloem, and potential latent buds against biotic and abiotic environmental hazards (fire, frost, scalding, insects, etc.) and may have contributed to the extensive paleolatitudinal distribution of the Glossopteridales during the Permian.
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8

Heneen, W. K., M. Gustafsson, K. Brismar, and G. Karlsson. "Interactions between Norway spruce (Picea abies) and Heterobasidion annosum. II. Infection of woody roots." Canadian Journal of Botany 72, no. 6 (June 1, 1994): 884–89. http://dx.doi.org/10.1139/b94-113.

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Woody roots, 2 – 4 mm in diameter, of Norway spruce (Picea abies) were inoculated with an S strain of Heterobasidion annosum. After 8 – 20 days the roots were prepared for examination by light microscopy as well as transmission and scanning electron microscopy. The roots had one or several periderms and sometimes remnant cortex cells on the surface. The fungal infection was restricted to the remnant cortex cells and the rhytidome after an incubation period of 20 days. Accumulation of granular materials, most likely phenolic in nature, prevailed in the infected periderm cells. Fungal hyphae enclosed in these materials showed signs of degeneration. Based on these results, we conclude that the rhytidome acts as a successful barrier to infection of the inner parts of the root for at least 20 days following inoculation with H. annosum. Both structural and chemical defence mechanisms are involved. Key words: Norway spruce, Heterobasidion annosum, root infection, woody roots, microscopy.
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9

Serra, Olga, Marçal Soler, Carolin Hohn, Rochus Franke, Lukas Schreiber, Salomé Prat, Marisa Molinas, and Mercè Figueras. "Silencing of StKCS6 in potato periderm leads to reduced chain lengths of suberin and wax compounds and increased peridermal transpiration." Journal of Experimental Botany 60, no. 2 (December 26, 2008): 697–707. http://dx.doi.org/10.1093/jxb/ern314.

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10

Schreiber, Lukas, Rochus Franke, and Klaus Hartmann. "Wax and suberin development of native and wound periderm of potato (Solanum tuberosum L.) and its relation to peridermal transpiration." Planta 220, no. 4 (September 17, 2004): 520–30. http://dx.doi.org/10.1007/s00425-004-1364-9.

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11

Chechenina, N. S., V. I. Lutov, A. A. Beliaev, A. A. Leliak, and A. I. Leliak. "INFLUENCE OF BACTERIAL STRAINS OF THE GENUS BACILLUS ON GROWTH PROCESSES AND TISSUE FORMATION IN THE SHOOTS OF REMONTANT RASPBERRIES." Bulletin of NSAU (Novosibirsk State Agrarian University), no. 3 (October 24, 2020): 76–85. http://dx.doi.org/10.31677/2072-6724-2020-56-3-76-85.

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The studies were carried out with the aim of revealing histological reactions in the shoots of remontant raspberries as an aspect of the growth-stimulating effect of pre-planting treatment of the root system of seedlings with strains of saprotrophic bacteria of the genus Bacillus. The observations in the model experiment were carried out in 2017-2018 in the production plantings of remontant raspberries of the agricultural artel “Sady Sibiri” in the Novosibirsk Region. Plants were treated before planting by soaking the root system in a working fluid containing a bioagent at a concentration of 1×105 CFU / ml. In terms of the totality of growth-stimulating effects, the most effective complex effect on remontant raspberry plants was provided by pre-planting treatment with B subtilis strain VKPM B-10641 and a mixture preparation Fitop 8.67. The number of replacement shoots increased by 45–69%, the length of replacement shoots - by 16–20%, the amount internodes - 1.2 times relative to control. Under the influence of the same bacterial bioagents in the shoots of remontant raspberries, an increase in the thickness of the peridermis by 20–25% relative to the control, an increase in the number of peridermal layers by 12–35%, suberinized (matured) layers of the peridermis by 30–48%, and the thickness of xylem by 12 –22% was observed. B subtilis VKPM B-10641 strain and Fitop 8.67 influence raspberry plants, the regularity of simultaneous stimulation of growth processes in the replacement shoots and the formation of mature peridermis. So it acts as an immunological barrier against phytopathogens, pests and abiotic stress factors. So the research proved it.
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12

Burrows, GE. "Axillary Meristem Ontogeny in Araucaria cunninghamii Aiton ex D Don." Australian Journal of Botany 34, no. 4 (1986): 357. http://dx.doi.org/10.1071/bt9860357.

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The presence of axillary meristems in apparently blank leaf axils from the main stem of 2-year-old Araucaria cunninghamii is demonstrated. These meristems are groups of cells of meristematic appearance, which possess neither a bud-like organisation nor vascular or pro-vascular connections with the central vascular cylinder. They are first discernible in the axils of the recently initiated leaves, where each meristem is delimited from the vacuolating cortex by a shell zone. The axillary meristems then persist indefinitely in an inhibited, undifferentiated state, unless stimulated to bud formation by decapitation of the terminal shoot apex. They are exogenous in origin but are subsequently buried beneath the stem surface by the formation of localised periderms, the bark patches, and are not abscissed when extensive periderm formation begins. A. cunninghamii is apparently unique amongst conifers in possessing distinct, long-lived, exogenously initiated meristems or bud primordia in macroscopically blank leaf axils. The meristems are found in most leaf axils not occupied by branch buds. In this respect A. cunninghamii differs from most conifers and approaches the typical condition of angiosperms. The axillary meristems are inter- mediate in form between previously described vegetative axillary structures in gymnosperms and angiosperms.
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13

Kotina, Ekaterina L., Patricia M. Tilney, Abraham E. van Wyk, Alexei A. Oskolski, and Ben-Erik van Wyk. "“Hairy” bark in Lannea schweinfurthii (Anacardiaceae): hyperhydric-like tissue formed under arid conditions." IAWA Journal 39, no. 2 (June 13, 2018): 221–33. http://dx.doi.org/10.1163/22941932-20170197.

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ABSTRACTA remarkable, almost fur-like “indumentum” of velvety “hairs” (sometimes referred to as “fungi”) occurs on the roots (and to a lesser extent also on the trunk) ofLannea schweinfurthiivar.stuhlmanniiand is known asvhulivhadzain the Venda language (Tshivenḓa). The hairs are traditionally used by the Venda people (Vhavenḓa) of the Limpopo Province of South Africa, for various biocultural purposes. A detailed anatomical study of the origin, structure and development of these unusual “hairs” showed that they are of peridermal origin and develop from dense clusters of phelloid cells which are scattered within the stratified phellem. These cells are capable of considerable radial elongation thus forming hair-like radial files of elongated phelloid cells. The “hairy” patches on the bark may also develop from lenticels which become hypertrophied. These clusters of phelloid cells resemble the hyperhydric tissue which is reportedly formed in periderm of stems exposed to a water-saturated environment in some plant species. The formation of hyperhydric-like tissue in roots and stems ofL. schweinfurthiivar.stuhlmanniioccurs, however, under relatively arid conditions. Since this tissue contains large intercellular spaces, it may also be regarded as a specialized type of aerenchymatous phellem. The adaptive significance, if any, of the phelloid “hairs” remains unknown.
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14

Evans, Lance S., and Phillip Dombrovskiy. "Anatomical Characteristics of Sunlight-induced Bark (Periderm) Coverages on Columnar Cacti of Central Mexico." Journal of Plant Studies 9, no. 2 (May 26, 2020): 20. http://dx.doi.org/10.5539/jps.v9n2p20.

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More than twenty-three species of tall, long-lived columnar cacti from a large variety of locations within the Americas show sunlight-induced periderm development on their stems. Periderm coverages lead to cactus morbidity and mortality. Our objective was to determine if periderm coverage patterns and anatomical characteristics of periderm formation differ among five cactus species located at a single site. Periderm coverages, patterns of periderm coverages and histological changes during the periderm formation process were determined for five native species of tall, long-lived columnar cacti in the Tehuacán Valley of Puebla, Mexico during May to June 2019. Periderm coverages and patterns of periderm on cactus surface varied among the species. On surfaces, some species had periderm form at crests initially, while one species had initial periderm form where troughs join. All species had the same internal tissues but the characteristics of these tissues varied among species. In response to periderm formation, one species retained its cuticle while one species retained its hypodermis intact and another produced cork cells inside the hypodermis. Overall, the histological changes that result from periderm formation were specific for each species and no pair of species showed the same responses to periderm formation. In conjunction with data from species from South America, eight distinct scenarios of histological manifestations were documented. Although, each of the five cactus species were in the same location and received the same amount of sunlight exposures, each species showed unique periderm coverages on surfaces, unique anatomical characteristics and unique anatomical responses. Thus, location was not the primary determinant of responses.
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15

Khandelwal, Sharda, and H. K. Goswami. "Periderm in Ophioglossaceae." Acta Societatis Botanicorum Poloniae 46, no. 4 (2015): 541–646. http://dx.doi.org/10.5586/asbp.1977.053.

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This paper describes the occurrence of periderm in three genera, <i>Botrychium</i> Swartz., <i>Helminthostachys</i> Kaulfuss, and <i>Ophioglossum</i> Linn. under field conditions. Not all plants of an area belonging to the same or different species possess it. Based on population survey it is suggested that production of functional cork cambium (phellogen), a feature unlike <i>Fillicenae</i> may be an inherited trait.
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16

Lev-Yadun, Simcha, and Roni Aloni. "Polar Patierns of Periderm Onfogeny, Their Relationship to Leaves and Buds, and the Control of Cork Formation." IAWA Journal 11, no. 3 (1990): 289–300. http://dx.doi.org/10.1163/22941932-90001185.

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Patterns of periderm ontogeny were studied in vigorously growing branches and leaders of Calotropis procera (Ait.) Ait. f., Carissa grandiflora A. DC., Ficus elastica Roxb., Ficus religiosa L. and Melia azedarach L. In all of these five woody species the periderm develops in clear polar patterns, with inhibitory zones, in which periderm formation is delayed, just beneath leaf bases and around dormant buds. A high rate of periderm production is induced by high sun irradiation in Calotropis procera. The polar patterns of periderm formation with retardation regions around leaves and buds probably indicate auxin involvement in the control mechanism of periderm differentiation. The role of both auxin and ethylene in periderm formation is discussed, as weIl as a proposed mechanism for rhytidome initiation.
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17

Sabba, Robert P., and Edward C. Lulai. "Immunocytological Analysis of Potato Tuber Periderm and Changes in Pectin and Extensin Epitopes Associated with Periderm Maturation." Journal of the American Society for Horticultural Science 130, no. 6 (November 2005): 936–42. http://dx.doi.org/10.21273/jashs.130.6.936.

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Potato (Solanum tuberosum L.) periderm forms a barrier at the surface of the tuber that protects it from infection and dehydration. Immature periderm is susceptible to excoriation (skinning injury), which results in costly storage loses and market quality defects. The periderm consists of three different cell types: phellem (skin), phellogen (cork cambium), and phelloderm (parenchyma-like cells). The phellogen serves as a lateral meristem for the periderm and is characterized by thin radial walls that are labile to fracture while the periderm is immature and the phellogen is actively dividing, thus rendering the tuber susceptible to excoriation. As the periderm matures the phellogen becomes inactive, its cell walls thicken and become resistant to fracture, and thus the tuber becomes resistant to excoriation. Little is known about the changes in cell wall polymers that are associated with tuber periderm maturation and the concurrent development of resistance to excoriation. Various changes in pectins (galacturonans and rhamnogalacturonans) and extensin may be involved in this maturational process. The objectives of this research were to compare immunolabeling of homogalacturonan (HG) epitopes to labeling of rhamnogalacturonan I (RG-I) and extensin epitopes to better understand the depositional patterns of these polymers in periderm cell walls and their involvement in tuber periderm maturation. Immunolabeling with the monoclonal antibodies JIM5 and JIM7 (recognizing a broad range of esterified HG) confirmed that HG epitopes are lacking in phellogen walls of immature periderm, but increased greatly upon maturation of the periderm. Labeling of a (1,4)-β-galactan epitope found in RG-I and recognized by the monoclonal antibody LM5 was abundant in phelloderm cell walls, but sparse in most phellem cell walls. LM5 labeling was very sparse in the walls of meristematically active phellogen cells of immature periderm, but increased dramatically upon periderm maturation. Deposition of a (1,5)-α-l-arabinan epitope found in RG-I and recognized by LM6 was abundant in phelloderm and phellogen cell walls, but was sparse in phellem cell walls. LM6 labeling of phellogen walls did not change upon periderm maturation, indicating that different RG-1 epitopes are regulated independently during maturation of the periderm. Labeling with the monoclonal antibody LM1 for an extensin epitope implied that extensin is lacking in phellem cell walls, but is abundant in phelloderm cell walls. Phellogen cell walls did not label with LM1 in immature periderm, but were abundantly labeled with LM1 in mature periderm. These immunolabeling studies identify pectin and extensin depositions as likely biochemical processes involved in the thickening and related strengthening of phellogen walls upon inactivation of the phellogen layer as a lateral meristem and maturation of the periderm in potato tuber. These results provide unique and new insight into the identities of some of the biological processes that may be targeted in the development of new technologies to enhance resistance to tuber skinning injury for improved harvest, handling and storage properties.
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18

John, Douglas L., Nigel C. Hughes, Monica I. Galaviz, Gerald O. Gunderson, and Ronald Meyer. "Unusually preserved Metaconularia manni (Roy, 1935) from the Silurian of Iowa, and the systematics of the genus." Journal of Paleontology 84, no. 1 (January 2010): 1–31. http://dx.doi.org/10.1666/09-025.1.

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The Welton Member of the Scotch Grove Formation at Shaffton Quarry, near Camanche, Iowa, is about 427 Ma old and contains numerous metaconulariid specimens, many of which are preserved in apex-downward orientation. Some of these show an unusual, splayed, “Maltese cross” configuration. Apex-downward configurations suggest rapid burial, consistent with the soft part preservation known in other taxa from this locality. The abundance of Metaconularia at Shaffton Quarry, and of topotype specimens of M. aspersa, the generic type species, permits evaluation of the degree of individual and intracollectional variation in peridermal ornament. Variation within and among individuals precludes reliance on ornamental differences in species differentiation in most cases. In view of these results we assign all Shaffton specimens to Metaconularia manni (Roy, 1935), and revise Metaconularia based on its type material from Europe and other material from Europe and North America. An exploratory phylogenetic analysis highlights aspects of character distribution within the genus, but the small number of characters states and possible taphonomic influences upon them limit confidence in the clade topology. Subgroups within the genus are characterized by larger, discoidal papillae, and by strong transverse corrugation and sinuous rows of smaller papillae. The genus itself comprises those conulariids with an external ornamentation of simple, round, small papillae, paired internal septae along the midlines, and a thin periderm that was to some degree pliable during life.
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19

Lev-Yadun, Simcha, and Roni Aloni. "Wound-Induced Periderm Tubes in the Bark of Melia Azedarach, Ficus Sycomorus and Platanus Acerifolia." IAWA Journal 12, no. 1 (1991): 62–66. http://dx.doi.org/10.1163/22941932-90001204.

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Tubes of periderm were induced experimentally by wounding stems of Melia azedarach L., Ficus sycomorus L. and Platanus acerifolia Willd. This wounding stimulated the formation of periderm tubes around those strands of phloem fibres which were exposed to the outside atmosphere. The differentiation of periderm tubes inside the bark is a defence reaction by which the wound-exposed fibres are isolated from the living cells of the bark. The regulating factors of wound-induced periderm tubes are probably ethylene and atmospheric air.
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20

PRITCHARD, M. K., and A. J. SIEMENS. "EFFECTS OF MEFLUIDIDE ON PERIDERM DEVELOPMENT AND STORAGE OF RUSSET BURBANK AND NORCHIP POTATOES." Canadian Journal of Plant Science 70, no. 2 (April 1, 1990): 575–83. http://dx.doi.org/10.4141/cjps90-072.

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The effects of preharvest, foliar applications of mefluidide (N-(2,4-dimethyl-5-(((trifluoromethyl)sulfonyl)amino)phenyl)-acetamide) to potato (Solanum tuberosum L.) plants on subsequent periderm development and on storage quality of Russet Burbank and Norchip tubers were investigated. Mefluidide application caused adnormal periderm development in tubers of both cultivars and resulted in increased tuber weight loss during storage due to enhanced water loss rather than to elevated respiration. Treatment with mefluidide 5 wk before harvest resulted in greater tuber weight loss in storage than treatment 7 wk before harvest. After ca. 26 wk storage, sucrose content generally increased in tubers from treated Russet Burbank plants but not in corresponding Norchip tubers. Despite a perceived periderm enhancement, the abnormal periderm development which increased water loss in stored tubers would suggest that mefluidide has little potential as a preharvest treatment to reduce tuber damage and improve storage of Russet Burbank and Norchip potatoes.Key words: Potato, mefluidide, storage, Russet Burbank, Norchip, periderm
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21

Kommineni, K. V., and D. C. Ramsdell. "An Anatomical Study of Prune Brown Line Disease and Immuno-localization of Tomato Ringspot Virus in Plum Bark." Plant Disease 81, no. 8 (August 1997): 855–61. http://dx.doi.org/10.1094/pdis.1997.81.8.855.

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Bark from the graft union of tomato ringspot virus (ToRSV) infected plum, symptomatic for brown line disease, showed anatomical changes characteristic of the wound response process. The wound tissue consisted of necrotic cells demarcated by pinkish purple necrophylactic periderm, whose function is to protect living tissues from detrimental effects associated with necrosing cells. However, formation of gray exophylactic periderm led to the sloughing off of the wound tissue and the necrophylactic periderm, resulting in discontinuity of the exophylactic periderm and secondary virus invasion into the wound site. The changes seen in the bark suggest that the hypersensitive response in plum rootstock bark to ToRSV is slow, allowing a systemic movement of the virus and development of a brown line (BL) along the scion and rootstock union. Necrophylactic periderm was not seen in the bark from the graft union of a healthy plum tree. In the graft union of a plum tree without a BL, but testing ToRSV-positive in the roots, localized areas of wound tissue with pinkish purple necrophylactic periderm developed only in the rootstock portion of the tree. Silver-enhanced protein A-colloidal gold immunolabeling was seen on the cell wall and in the cytoplasm of bark tissue from the BL region of scion and rootstock and leaves from the rootstock suckers.
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22

Harrison, Howard F., and Joseph K. Peterson. "Sweet Potato Periderm Components Inhibit Yellow Nutsedge (Cyperus esculentus) Growth." Weed Technology 8, no. 1 (March 1994): 168–71. http://dx.doi.org/10.1017/s0890037x00039397.

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Sequential extraction and chromatographic procedures were used to isolate inhibitors of yellow nutsedge growth from sweet potato periderm tissue. Most of the inhibitory activity was found in a single high pressure liquid chromatography peak that contained 1.2% of the periderm dry weight. Concentration-response data indicated that yellow nutsedge is highly sensitive to this fraction. Several other fractions inhibited yellow nutsedge root growth, but they did not compose a major portion of the inhibitory capacity of the periderm extracts.
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23

Harrison, Howard F., Joseph K. Peterson, Christopher A. Clark, and Maurice E. Snook. "Sweetpotato Periderm Components Inhibit In Vitro Growth of Root Rotting Fungi." HortScience 36, no. 5 (August 2001): 927–30. http://dx.doi.org/10.21273/hortsci.36.5.927.

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Sweetpotato [Ipomoea batatas (L.) Lam.] periderm components were tested for their effect on four fungi that infect sweetpotato roots: Fusarium oxysporum Schlecht. f. sp. batatas (Wollenw.) Snyd. & Hans. and F. solani (Sacc.) Mart., both of which cause stem and root disease; and Lasiodiplodea theobromae (Pat.) Griffon & Maubl. and Rhizopus stolonifer (Ehr. ex Fr.) Lind., both of which cause storage root disease. Sequential extracts of `Regal' sweetpotato periderm with hexane, methanol, and 50% methanol were inhibitory to the four fungi when incorporated into potato dextrose agar medium in petri dish bioassays. The methanol and 50% methanol extracts were much more active than the hexane extract and were combined for further study. Sephadex LH-20 column chromatography of the combined extracts, followed by bioassay with F. oxysporum indicated that the most inhibitory fraction contained the least polar components of the extract. Resin glycosides isolated from `Regal' periderm inhibited F. oxysporum, but the glycosides exhibited little concentration effect and were not as active on a tissue weight basis as other components. Periderm extracts from 10 sweetpotato clones exhibited large differences in inhibitory activity in bioassays with the four fungi. The sensitivity of the fungi to inhibition by the periderm extracts suggests that periderm components may provide protection against soil pathogens, but a relationship between such components and disease resistance was not established.
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24

Orduño-Cruz, Andrés, and Teresa Terrazas. "Anatomía de la corteza de tres especies de leguminosas I. Origen y desarrollo." Botanical Sciences, no. 63 (May 25, 2017): 51. http://dx.doi.org/10.17129/botsci.1567.

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Origin and development of bark Pithecellobium dulce, Acacia cochliacantha and A. farnesiana were studied anatomically. The periderm in the three species has a subepidermic origin, near the apex of the branches formed during the present growth season. Fast periderm development probably has ecological adaptations, since periderm protects from high temperatures and diseccation and also may act as an alternative photosynthetic tissue during the deciduous season. Species described show a thin, fibrous bark, generally smooth with abundant lenticels and distinctive odor. They possess sieve tube members arranged in groups or members solitary with compound sieve plate, axial parenchyma diffuse or in bands, fibers arranged in bands, and some dilated rays. They form a single periderm, without rhytidome. These characteristics are shared with other legumes, but they are distinctive by their ray size
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25

Pereira, Ariana Mota, Edgard Augusto de Toledo Picoli, Mateus de Paula Gomes, Kharen Priscilla de Oliveira Salomão Petrucci, Aline da Silva Bhering, Renata Ranielly Pedroza Cruz, Ana Izabella Freire, and Fernando Luiz Finger. "Regeneration of the damage periderm of potato tuber as a result of the temperature of curing." Research, Society and Development 9, no. 9 (August 13, 2020): e106996700. http://dx.doi.org/10.33448/rsd-v9i9.6700.

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It is acknowledged that mechanical damage is a major cause of post-harvest losses of potato tubers and the curing is an indispensable process to increase resistance to excoriation. Furthermore, the use of lower curing temperatures is required to maintain the quality and prolong the durability of the tubers. However, they may not allow adequate regeneration of the damage periderm, besides this effect being variable among genotypes. The present study evaluates histological outcomes in the periderm derived from the mechanical damage through a simulation of excoriation, as it is the most common during the harvest and post-harvest stages. Therefore, the objective of this study was to determine the effect of reducing the curing temperature on the number of layers and on the thickness of the damage periderm of potato tubers of cv. Innovator. Histometric analysis of the cork, phellogen, phelloderm and the total periderm of tuber, was performed using the Image-Pro Plus software (MediaCybernetics) after curing for 15 days. The number of layers and thickness of each periderm structural layers were determined from six measurements for each repetition. After curing, there was no formation of the cork and phelloderm in the tubers conducted at 8 ° C under the excoriation treatment, while all components of the periderm were formed at 14 and 20 °C. At 8 and 14 °C, the phellogen differentiated similarly in tubers conducted at control and mechanical damage treatments, while at 20 °C the thickness did not differ in any component of the periderm. The phellogen at 14 and 20 °C did not differ in the number of layers and thickness. The visual aspect of the tuber injuries at 14 and 20 °C emphasizing the regeneration. It is concluded that the reduction of the curing temperature to 8 °C provided slower cell regeneration. However, it is possible to conduct the curing procedure at 14 °C, without compromising the formation of the damage periderm. The cultivar Innovator has rapid cell regeneration at higher curing temperatures, therefore it is recommended that the tubers of this cultivar be cured at 14 or 20 ° C. The study evaluates the mechanical damage through a simulation of the damage by excoriation. The however, for a better understanding of the formation of the damage periderm, it is interesting that other studies evaluate different types of damage, such as impact, comprehension and abrasion, in order to assess the regeneration capacity according to the damage of this cultivar.
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26

Weiland, Jerry E., and Glen R. Stanosz. "The Histology of Hybrid Poplar Clones Inoculated with Septoria musiva." Plant Disease 91, no. 12 (December 2007): 1524–30. http://dx.doi.org/10.1094/pdis-91-12-1524.

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Septoria musiva causes stem cankers that severely limit production of susceptible hybrid poplars in eastern North America. A field experiment was conducted with resistant clone DN34 and susceptible clone NC11505 in order to (i) identify tissues colonized by the pathogen, (ii) describe tissue responses to S. musiva, and (iii) determine whether tissue responses to S. musiva differed between hybrid poplar clones. Branches of each clone were inoculated by removing the fourth or fifth fully expanded leaf and placing an agar plug colonized by an aggressive isolate of S. musiva over the wound. Seven weeks after inoculation, branches were harvested and prepared for histology. Data from nonwounded control, wounded control, and wounded and inoculated stems were collected and analyzed for effects of clone and treatment. In general, fungal colonization was more extensive in NC11505 and exophylactic and necrophylactic periderms (NPs) of clone DN34 were significantly thicker than those of NC11505, regardless of treatment. The number of NPs produced and the distance from the epidermis to the outermost layer of phellem were significantly affected by the pathogen. Inoculated stems of clone DN34 developed a single NP that formed closer to the wound surface than in wounded controls. In contrast, inoculated stems of NC11505 developed successive NPs and the first NP formed further from the wound surface than in wounded controls. These two host responses to inoculation, as well as measures of exophylactic and necrophylactic periderm thickness, may be useful as markers for the selection of poplar resistant to damage by S. musiva.
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27

Chen, Yun-Hao, Jannis Straube, Bishnu P. Khanal, Moritz Knoche, and Thomas Debener. "Russeting in Apple Is Initiated After Exposure to Moisture Ends—I. Histological Evidence." Plants 9, no. 10 (September 30, 2020): 1293. http://dx.doi.org/10.3390/plants9101293.

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Russeting (periderm formation) is a critical fruit-surface disorder in apple (Malus × domestica Borkh.). The first symptom of insipient russeting is cuticular microcracking. Humid and rainy weather increases russeting. The aim was to determine the ontogeny of moisture-induced russeting in ‘Pinova’ apple. We recorded the effects of duration of exposure to water and the stage of fruit development at exposure on microcracking, periderm formation and cuticle deposition. Early on (21 or 31 days after full bloom; DAFB) short periods (2 to 12 d) of moisture exposure induced cuticular microcracking—but not later on (66 or 93 DAFB). A periderm was not formed during moisture exposure but 4 d after exposure ended. A periderm was formed in the hypodermis beneath a microcrack. Russeting frequency and severity were low for up to 4 d of moisture exposure but increased after 6 d. Cuticle thickness was not affected by moisture for up to 8 d but decreased for longer exposures. Cuticular ridge thickness decreased around a microcrack. In general, moisture did not affect cuticular strain release. We conclude that a hypodermal periderm forms after termination of moisture exposure and after microcrack formation. Reduced cuticle deposition may cause moisture-induced microcracking and, thus, russeting.
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28

Keifenheim, Daniel, and Cindy Tong*. "Expression of Anthocyanin Genes in Potato Periderm." HortScience 39, no. 4 (July 2004): 754B—754. http://dx.doi.org/10.21273/hortsci.39.4.754b.

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Anthocyanins are a class of flavonoids that are responsible for pigments in flowers, fruit, and potato periderm. Developing `Norland' potatoes synthesize anthocyanins in periderm tissue when the tubers are mere swollen stolon tips. As the tubers enlarge, anthocyanin accumulation seems to stop, and anthocyanins synthesized early in development seem to be diluted as the tubers enlarge. Expression of dihydroflavonol reductase (DFR) limits anthocyanin synthesis in grape and maize fruit, and in petunia and snapdragon flowers. However, DFR expression in periderm tissue occurred throughout tuber development (Hung et al., 1999). To determine if expression of late anthocyanin pathway genes limit anthocyanin synthesis in developing potato tubers, we performed RNA gel blot analyses. Expression of leucoanthocyanidin dioxygenase and UDP glucose: flavonoid 3-O-glucosyl transferase was observed in swollen stolon tips but not in periderm of later tuber development stages. Surprisingly, expression was also observed in cortex tissue, although that tissue remained white throughout tuber growth.
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29

Biggs, A. R. "Wound age and infection of peach bark by Cytospora leucostoma." Canadian Journal of Botany 64, no. 10 (October 1, 1986): 2319–21. http://dx.doi.org/10.1139/b86-303.

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Peach bark wounds of varying ages were inoculated with mycelium of Cytospora leucostoma (Pers.) Fr., and colonization frequency and extent were determined. Noninoculated wounds of similar ages and in close proximity to inoculated wounds were also sampled and examined histologically for morphological and histochemical changes associated with nonspecific plant defense reactions, including lignification and formation of lignosuberized tissue and new periderm. Results demonstrated that lignified and lignosuberized tissues significantly decreased the rate of fungal colonization, whereas new periderm with at least three cells thickness of new phellem completely inhibited fungal colonization. The critical period regarding effective periderm formation was between 10 and 14 days postwounding.
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30

Scott, W. J., H. Nau, W. Wittfoht, and H. J. Merker. "Ventral duplication of the autopod: chemical induction by methoxyacetic acid in rat embryos." Development 99, no. 1 (January 1, 1987): 127–36. http://dx.doi.org/10.1242/dev.99.1.127.

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Administration of 2-methoxyethanol to pregnant rats on day 12 of gestation induced ventral duplication of the autopod, presumably via its oxidative metabolite, methoxyacetic acid. Morphological observations indicate that the limb bud periderm is severely damaged by methoxyacetic acid so that large patches of this structure are actually missing during an extended period of limb bud development. A high concentration of methoxyacetic acid (10 mM) was found in the extraembryonic fluid and we postulate that the damage to the periderm was initiated from this extraembryonic exposure. The ventral duplication of the autopod is thought to arise through an attempt by the embryo to repair the periderm lesion.
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31

Adepoju, A. D., J. A. Adebisi, J. K. Odusote, I. I. Ahmed, and S. B. Hassan. "Preparation of Silica from Cassava Periderm." Journal of Solid Waste Technology and Management 42, no. 3 (August 1, 2016): 216–21. http://dx.doi.org/10.5276/jswtm.2016.216.

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32

Graça, José, and Helena Pereira. "THE PERIDERM DEVELOPMENT IN QUERCUS SUBER." IAWA Journal 25, no. 3 (2004): 325–35. http://dx.doi.org/10.1163/22941932-90000369.

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In the cork oak (Quercus suber L.), the phellogen differentiates during the first year of growth in the cell layer immediately under the epidermis and divides to form 3–6 suberized phellem cells. Division of the phellogen only occurs after suberization of the previous divided cell. During the first four years of growth, the phellem cells have tannin-filled lumens and it is only in the 5th to 7th years that they acquire the characteristics of ʻadultʼ cork cells with empty lumens and thin suberized walls. The lenticels are formed by the lenticular phellogen, which differentiates under the stomata and has a high meristematic activity. In this region, the cells are unsuberized, with a loose arrangement and intercellular voids, constituting the filling or complementary tissue. After three years, the lenticels appear as small protuberances that soon become conspicuous. Inclusions of sclerenchymatous nodules and isolated sclereids occur occasionally mostly in the vicinity of, or in, the lenticels.
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33

D'Antonio, Michael P., and C. Kevin Boyce. "Arborescent lycopsid periderm production was limited." New Phytologist 228, no. 2 (July 10, 2020): 741–51. http://dx.doi.org/10.1111/nph.16727.

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34

Villavicencio, Lucia E., Sylvia M. Blankenship, G. Craig Yencho, Judith F. Thomas, and C. David Raper. "Temperature Effect on Skin Adhesion, Cell Wall Enzyme Activity, Lignin Content, Anthocyanins, Growth Parameters, and Periderm Histochemistry of Sweetpotato." Journal of the American Society for Horticultural Science 132, no. 5 (September 2007): 729–38. http://dx.doi.org/10.21273/jashs.132.5.729.

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Sweetpotatoes [Ipomoea batatas (L.) Lam.] often experience significant epidermal loss during harvest and postharvest handling. Skin loss causes weight loss, shriveling of the root surface, and increased susceptibility to pathogen attack as well as poor appearance. It is not known if sweetpotatoes show variation in skin adhesion, cell wall enzyme activity and components, and growth parameters with growth temperature or if skin loss can be explained on the basis of variation among these variables. Skin adhesion, polygalacturonase (PG) and pectin methylesterase (PME) activity, lignin, anthocyanin, and dry matter content were measured in the periderm of ‘Beauregard’ roots grown at various temperatures under controlled conditions. Biomass dry matter content, storage root yield, root length, diameter, and weight at harvest were recorded. Histochemical and anatomical characteristics of periderm of roots were studied. Growth temperature affected skin adhesion, PG and PME activity, periderm and biomass dry matter content, yield, storage root weight, and diameter. High temperatures (34/31 °C day/night) yielded roots that were smaller and more resistant to skin loss. These roots had a periderm composed of more cell layers with a lower dry matter content than roots grown at lower and intermediate temperatures (27/24 °C and 20/17 °C). In cured roots, the correlation between skin adhesion and PG activity was negative (r = 0.544, P = 0.0006) and positive between skin adhesion and PME (r = 0.319, P = 0.05). For most of the variables studied, the interaction between growing temperature and curing was significant. Curing improved skin adhesion, but the effect of curing was dependent on the root growth temperature. The periderm of roots grown at higher temperatures was thicker and had more layers than that of roots grown at lower temperatures. Histochemical studies of the periderm of sweetpotato showed that the anatomical and structural composition of the cell walls differ depending on growth temperature.
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35

Zaslavskaya, N. "Evolutionary trends and facial control of Chitinozoa." Paleontological Society Special Publications 6 (1992): 326. http://dx.doi.org/10.1017/s2475262200008868.

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Chitinozoa is an organic world group, the nature of which is not yet known. However, Chitinozoa is a uniform natural group of the organic world with a definite stratigraphical position (O-D). I suggest to use solely peridermal structures to specify evolutional trends of Chitinozoa.1. The change of carinae that forms the morphological succession Cyathochitina calix-C. campanulaeformis-C. kuckersiana. This succession of species encompasses the early-middle Ordovician interval.2. The change in the structure of longitudinal ridges that features the evolutionary succession Hercochitina repsinata-H. lindsaensis-H. crickmay at the middle-late Ordovician interval of the south part of Ontario.3. The change in the ultrastructure of peridermal tissue. It shows well through the structure of appendices in the succession Ancyrochitina ancyrea-A. alveolata-A. siberica, llandovery-wenlock of the Siberian platform and ludlowpridoli of Europe and North America.The points of peridermal appendix structure might be used for facial analysis. So, basal appendices change from simple branchwise up to complex anastomosis and loop-like during the change of the surrounding from shallow-water shelf up to a deep-water one, forming the morphology succession Ancyrochitina-Clathrochitina. Thus, evolutional trends of Chitinozoa and facial analysis might be based on a detailed study of peridermal structure morphology.
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36

Peterson, Joseph K., and Howard F. Harrison. "Differential Inhibition of Seed Germination by Sweetpotato (Ipomoea batatas) Root Periderm Extracts." Weed Science 39, no. 1 (March 1991): 119–23. http://dx.doi.org/10.1017/s0043174500057970.

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The effect of sequential hexane, ethyl acetate, and aqueous methanol extracts of ‘Regal’ sweetpotato periderm on seed germination of sweetpotato, proso millet, and seven weed species was studied. The hexane extract, which contained the nonpolar components of the periderm tissue, was least inhibitory. It inhibited velvetleaf, proso millet, black nightshade, and redroot pigweed germination, and maximum inhibition was 56% for black nightshade at 200 mg of periderm extracted ml–1. The ethyl acetate fraction was inhibitory to proso millet, velvetleaf, black nightshade, goosegrass, tall morningglory, coffee senna, and redroot pigweed. The estimated I50for ethyl acetate ranged from 17 mg periderm extracted ml–1for black nightshade to 201 mg ml–1for coffee senna. Sweetpotato, tall morningglory, and eclipta germination was not inhibited by this extract at the concentrations tested. The aqueous methanol extract was much more inhibitory than the hexane or ethyl acetate extracts, and there was considerable variation between species in response to this extract The I50estimates for the aqueous methanol extract were 0.5, 0.6, 2.8, 4.4, 5.1, 9.6, 15.7, 21.0, and 25.8 mg ml–1for velvetleaf, proso millet, black nightshade, goosegrass, sweetpotato, tall morningglory, eclipta, coffee senna, and pigweed, respectively.
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37

Enebak, Scott A., and Robert A. Blanchette. "Canker formation and decay in sugar maple and paper birch infected by Cerrenaunicolor." Canadian Journal of Forest Research 19, no. 2 (February 1, 1989): 225–31. http://dx.doi.org/10.1139/x89-031.

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Cerrenaunicolor (Bull.: Fr.) Murr. (= Daedaleaunicolor) (Aphyllophorales, Polyporaceae) was found to cause a canker rot on two northern hardwood tree species, sugar maple (Acersaccharum Marsh.) and paper birch (Betulapapyrifera Marsh.). Pathogenicity of the fungus was determined by inoculation and examination of cankers 6 months, 1.5 years, and 2.5 years later. The two isolates used were found to differ in pathogenicity. Chemical and morphological barriers formed to compartmentalize the fungus. A zone of enhanced cell wall lignification and the formation of suberized impervious cells which composed the necrophylactic periderm in the host were observed. Xylem discoloration, callus formation, and periderm layers were more pronounced in maple than in birch. Cerrenaunicolor moved past host barriers via a mass of hyphae which annually penetrated weak points in the necrophylactic periderm and subsequently killed the adjacent cambium. Once past the necrophylactic periderm and into the xylem, C. unicolor was an aggressive decay organism which caused an extensive white rot. In naturally infected trees, columns of decay were two or three times longer than the cankers. Multiple zones of decayed and discolored wood were present in the xylem as a result of repeated attacks by the fungus.
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38

Oralová, Veronika, Joana Teixeira Rosa, Daria Larionova, P. Eckhard Witten, and Ann Huysseune. "Multiple epithelia are required to develop teeth deep inside the pharynx." Proceedings of the National Academy of Sciences 117, no. 21 (May 12, 2020): 11503–12. http://dx.doi.org/10.1073/pnas.2000279117.

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To explain the evolutionary origin of vertebrate teeth from odontodes, it has been proposed that competent epithelium spread into the oropharyngeal cavity via the mouth and other possible channels such as the gill slits [Huysseune et al., 2009,J. Anat.214, 465–476]. Whether tooth formation deep inside the pharynx in extant vertebrates continues to require external epithelia has not been addressed so far. Using zebrafish we have previously demonstrated that cells derived from the periderm penetrate the oropharyngeal cavity via the mouth and via the endodermal pouches and connect to periderm-like cells that subsequently cover the entire endoderm-derived pharyngeal epithelium [Rosa et al., 2019,Sci. Rep.9, 10082]. We now provide conclusive evidence that the epithelial component of pharyngeal teeth in zebrafish (the enamel organ) is derived from medial endoderm, as hitherto assumed based on position deep in the pharynx. Yet, dental morphogenesis starts only after the corresponding endodermal pouch (pouch 6) has made contact with the skin ectoderm, and only after periderm-like cells have covered the prospective tooth-forming endodermal epithelium. Manipulation of signaling pathways shown to adversely affect tooth development indicates they act downstream of these events. We demonstrate that pouch–ectoderm contact and the presence of a periderm-like layer are both required, but not sufficient, for tooth initiation in the pharynx. We conclude that the earliest interactions to generate pharyngeal teeth encompass those between different epithelial populations (skin ectoderm, endoderm, and periderm-like cells in zebrafish), in addition to the epithelial–mesenchymal interactions that govern the formation of all vertebrate teeth.
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39

Fennell, Anne, and Emily Hoover. "Photoperiod Influences Growth, Bud Dormancy, and Cold Acclimation in Vitis labruscana and V. riparia." Journal of the American Society for Horticultural Science 116, no. 2 (March 1991): 270–73. http://dx.doi.org/10.21273/jashs.116.2.270.

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The grape species Vitis labruscana Bailey and V. riparia Michx. were subjected to a decreasing photoperiod at constant moderate temperatures to determine whether acclimation occurred in response to a shortening photoperiod. Cane growth, periderm development, killing temperature of the primary bud, and bud dormancy were measured in vines receiving a natural photoperiod (ND), a simulated long photoperiod of 15 hours (LD), and shorter photoperiods of 14, 13, or 12 hours (SD). The LD treatment was effective at maintaining growth and inhibiting periderm development and the onset of bud dormancy in V. labruscana. Cane growth rate with all SD treatments decreased as compared to the LD regime. A significant increase in periderm development occurred with the 12-hour SD treatment. Similarly, the onset of bud dormancy was promoted by the 12-hour SD in V. labruscana. The primary bud killing temperature was 1C lower in V. labruscana under the 12-hour SD than under the LD treatment. In contrast, the LD treatment neither maintained growth nor fully inhibited periderm development and the onset of dormancy in V. riparia. The decrease in the cane growth rate upon exposure to SD was significantly greater in V. riparia than V. labruscana. Periderm development was observed in both the SD and its respective LD-treated V. riparia vines. However, the rate of periderm development was significantly greater in the SD vines than in the LD vines. The onset of bud dormancy was promoted by 13-hour SD in V. riparia. Similarly, the primary bud killing temperature was 2 to 3C lower in V. riparia upon exposure to SD. Vitis riparia has a longer critical photoperiod than V. labruscana and appears to be more sensitive to changes in light intensity or light quality. While the change in freezing tolerance in response to short photoperiods is small, the photoperiod response at a longer critical photoperiod, when combined with lower temperatures, will promote an earlier and possibly more rapid cold acclimation in V. riparia than in V. labruscana.
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40

Harris, M. J., and D. M. Juriloff. "Eyelid development and fusion induced by cortisone treatment in mutant, lidgap-Miller, foetal mice. A scanning electron microscope study." Development 91, no. 1 (February 1, 1986): 1–18. http://dx.doi.org/10.1242/dev.91.1.1.

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In normal mice the eyelids grow across the eye and fuse together during days 15 and 16 of gestation, and the mice are born with their eyes closed. In mutant lgM1/lgM1 (lidgap-Miller) foetuses this growth and fusion does not occur and the mice are born with their eyes open. A single prenatal treatment with cortisone on day 14 of gestation masks the genetic defect, and the mice are born with their eyes closed. In the present study, a scanning electron microscope was used to investigate: (1) whether eyelid closure in cortisone-treated lgM1/lgM1 foetuses differs from that in normal foetuses of the CBA/J and ICR/M1 strains and, if so, how; and (2) how developing eyelids of untreated lgM1/lgM1 foetuses differ from normal. The induced closure differs from normal. During their growth, eyelids of treated mutant foetuses have a deficiency of rounded periderm cells at their margins; the margin cells agglomerate and flatten prematurely. In closed eyes of treated mutants there is a gap between periderm cells of the upper and lower eyelids along part of the fusion line. Fusion is completed late, during day 17. Maturation of the head periderm is advanced in treated lgM1/lgM1 foetuses on day 16, relative to normal CBA/J and untreated lgM1/lgM1 foetuses. Untreated lgM1/lgM1 foetuses differ from normal in that the eyelids never cover the eye and lack rounded periderm cells at their perimeter. The periderm cells present form a flattened band along the eyelid margin rather than, as in normal eyelids, along the fusion line. The results of the cortisone study suggest that the route to eyelid closure in mice may not be narrowly canalized either in cell morphology or number, or in timing, and that closed eyes may be achieved after cortisone treatment in lgM1/lgM1 foetuses as part of an induced maturation of the periderm.
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41

Decombeix, Anne-Laure, and Jean Galtier. "Periderm Production in the Mississippian Cladoxylopsid Cladoxylon taeniatum and a Review of Periderm Occurrence in Paleozoic Plants." International Journal of Plant Sciences 182, no. 6 (July 1, 2021): 430–44. http://dx.doi.org/10.1086/714284.

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42

Ford, Robert C., Heyo Van Iten, and George R. Clark. "Microstructure and composition of the periderm of conulariids." Journal of Paleontology 90, no. 3 (May 2016): 389–99. http://dx.doi.org/10.1017/jpa.2016.63.

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AbstractTransmitted light and scanning electron imaging of sectioned specimens ofConulariaandParaconularia, prepared using HCl etching and critical point drying, revealed that their periderm is composed of extremely thin (approximately 0.5–3 µm), variably distinct microlamellae that are alternately organic poor and organic rich. Organic-rich microlamellae are cross-connected by slender strands of organic matter originally embedded in calcium phosphate, which in etched specimens has been dissolved. Microlamellae may be organized in thicker (approximately 5–75 µm) layers, or macrolamellae, that vary in color and organic matter content, possibly owing to changes in the ambient paleoenvironment. Thickening of the periderm to form transverse ribs and internal carinae was achieved through gradual thickening of individual microlamellae. In the core of the transverse ribs and internal carinae the distinction between organic-rich and organic-poor microlamellae may be reduced, owing to organic material becoming dominant over (former) mineral matter or vice versa. Combined with observations of plicated aperture closure in thin-walled conulariids, includingArchaeoconularia slateri(Reed, 1933) (Upper Ordovician, Scotland) showing smooth folding of midline carinae through angles greater than 90°, these results suggest a structure and original flexibility in the organic-rich biocomposite forming the conulariid periderm that supports its homology to the chitinous lamellar periderm of coronate scyphozoans.
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43

Macnee, Nikolai C., Ria Rebstock, Ian C. Hallett, Robert J. Schaffer, and Sean M. Bulley. "A review of current knowledge about the formation of native peridermal exocarp in fruit." Functional Plant Biology 47, no. 12 (2020): 1019. http://dx.doi.org/10.1071/fp19135.

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The outer skin layer in any plant is essential in offering a protective barrier against water loss and pathogen attack. Within fleshy fruit, the skin supports internal cell layers and can provide the initial cues in attracting seed-dispersing animals. The skin of a fruit, termed the exocarp, is a key element of consumer preference and a target for many breeding programs. Across fruiting species there is a huge diversity of exocarp types and these range from a simple single living cell layer (epidermis) often covered with a waxy layer, to complex multicellular suberised and dead cell layers (periderm), with various intermediate russet forms in between. Each exocarp can be interspersed with other structures such as hairs or spines. The epidermis has been well characterised and remains pluripotent with the help of the cells immediately under the epidermis. The periderm, in contrast, is the result of secondary meristematic activity, which replaces the epidermal layers, and is not well characterised in fruits. In this review we explore the structure, composition and mechanisms that control the development of a periderm type fruit exocarp. We draw upon literature from non-fleshy fruit species that form periderm tissue, from which a considerable amount of research has been undertaken.
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44

Thangavel, Tamilarasan, Robert S. Tegg, and Calum R. Wilson. "Toughing It Out—Disease-Resistant Potato Mutants Have Enhanced Tuber Skin Defenses." Phytopathology® 106, no. 5 (May 2016): 474–83. http://dx.doi.org/10.1094/phyto-08-15-0191-r.

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Common scab, a globally important potato disease, is caused by infection of tubers with pathogenic Streptomyces spp. Previously, disease-resistant potato somaclones were obtained through cell selections against the pathogen’s toxin, known to be essential for disease. Further testing revealed that these clones had broad-spectrum resistance to diverse tuber-invading pathogens, and that resistance was restricted to tuber tissues. The mechanism of enhanced disease resistance was not known. Tuber periderm tissues from disease-resistant clones and their susceptible parent were examined histologically following challenge with the pathogen and its purified toxin. Relative expression of genes associated with tuber suberin biosynthesis and innate defense pathways within these tissues were also examined. The disease-resistant somaclones reacted to both pathogen and toxin by producing more phellem cell layers in the tuber periderm, and accumulating greater suberin polyphenols in these tissues. Furthermore, they had greater expression of genes associated with suberin biosynthesis. In contrast, signaling genes associated with innate defense responses were not differentially expressed between resistant and susceptible clones. The resistance phenotype is due to induction of increased periderm cell layers and suberization of the tuber periderm preventing infection. The somaclones provide a valuable resource for further examination of suberization responses and its genetic control.
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45

Richardson, Rebecca J., Nigel L. Hammond, Pierre A. Coulombe, Carola Saloranta, Heidi O. Nousiainen, Riitta Salonen, Andrew Berry, et al. "Periderm prevents pathological epithelial adhesions during embryogenesis." Journal of Clinical Investigation 124, no. 9 (August 18, 2014): 3891–900. http://dx.doi.org/10.1172/jci71946.

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46

Kousa, Y. A., R. Roushangar, N. Patel, A. Walter, P. Marangoni, R. Krumlauf, O. D. Klein, and B. C. Schutte. "IRF6 and SPRY4 Signaling Interact in Periderm Development." Journal of Dental Research 96, no. 11 (July 21, 2017): 1306–13. http://dx.doi.org/10.1177/0022034517719870.

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Rare mutations in IRF6 and GRHL3 cause Van der Woude syndrome, an autosomal dominant orofacial clefting disorder. Common variants in IRF6 and GRHL3 also contribute risk for isolated orofacial clefting. Similarly, variants within genes that encode receptor tyrosine kinase (RTK) signaling components, including members of the FGF pathway, EPHA3 and SPRY2, also contribute risk for isolated orofacial clefting. In the mouse, loss of Irf6 or perturbation of Fgf signaling leads to abnormal oral epithelial adhesions and cleft palate. Oral adhesions can result from a disruption of periderm formation. Here, we find that IRF6 and SPRY4 signaling interact in periderm function. We crossed Irf6 heterozygous ( Irf6+/–) mice with transgenic mice that express Spry4 in the basal epithelial layer ( TgKRT14::Spry4). While embryos with either of these mutations can have abnormal oral adhesions, using a new quantitative assay, we observed a nonadditive effect of abnormal oral epithelial adhesions in the most severely affected double mutant embryos ( Irf6+/–;TgKRT14::Spry4). At the molecular level, the sites of abnormal oral adhesions maintained periderm-like cells that express keratin 6, but we observed abnormal expression of GRHL3. Together, these data suggest that Irf6 and RTK signaling interact in regulating periderm differentiation and function, as well as provide a rationale to screen for epistatic interactions between variants in IRF6 and RTK signaling pathway genes in human orofacial clefting populations.
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47

Brown, SM, and KB Walsh. "Anatomy of the Legume Nodule Cortex: Species Survey of Suberisation and Intercellular Glycoprotein." Functional Plant Biology 23, no. 2 (1996): 211. http://dx.doi.org/10.1071/pp9960211.

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Nodules of 29 species from 23 legume genera were examined for suberisation and glycoprotein deposits. Extensive suberisation of the nodule outer cortex to form a peridem was considered a primitive feature, common to non-legume and caesalpinioid nodules. The periderm was less extensive in nodules of Mimosoideae and Papilionoideae. Vascular bundles within the nodule were always surrounded by a vascular endodermis, defined by the presence of suberin on radial walls. Suberisation of the tangential walls of this endodermis was considered to be a primitive feature (present in all species examined of Caesalpinioideae and Mimosoideae, and in 10 out of 21 Papilionoideae) which may limit solute import to and export from the nodule. Glycoprotein was observed in the apoplast of the cortex in the three papilionoid species examined, but was absent in the caesalpinioid species examined. The common endodermis was recognised as an advanced feature, present only in certain species of the subfamily Papilionoideae (5 of 7, and 11 of 15 species of indeterminate and determinate nodule growth respectively). A membrane impermeant dye (lucifer yellow-CH), supplied in the rhizosphere under a mild vacuum, was observed to infiltrate through the cortex and into the infected zone in caesalpinioid nodules, and as far as the inner cortex in mimosoid and papilionoid nodules. Thus the common endodermis does not serve as an apoplastic barrier, and is unlikely to serve as a significant oxygen 'diffusion barrier'.
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48

Stevenson, Joshua F., Mark A. Matthews, and Thomas L. Rost. "The Developmental Anatomy of Pierce's Disease Symptoms in Grapevines: Green Islands and Matchsticks." Plant Disease 89, no. 6 (June 2005): 543–48. http://dx.doi.org/10.1094/pd-89-0543.

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Symptoms of Pierce's disease were studied in an anatomical context from infected grapevines (Vitis species) collected from field sites within Napa Valley, CA. Two symptoms, green islands and matchsticks, are reported in this study. Green islands formed as a result of incomplete initiation of the phellogen. In regions of the stem where a phellogen and subsequent periderm arose, immediately exterior tissue was cut off, causing it to brown. In regions of the stem where no periderm is formed, the exterior tissues remained green. Consequently, the stem is mottled with both green living epidermis and brown dying epidermis as determined by the presence or absence of an underlying periderm. Matchsticks formed when the leaf lamina separated from the petiole, and the petiole remained attached to the stem. Lamina broke off from the petioles consistently in a fracture zone where xylem from the petiole anastomoses into the five major veins of the leaf. No separation layer was found to explain this pseudoabscission.
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49

Allen, Eric A., P. V. Blenis, and Y. Hiratsuka. "Early symptom development in lodgepole pine seedlings infected with Endocronartium harknessii." Canadian Journal of Botany 68, no. 2 (February 1, 1990): 270–77. http://dx.doi.org/10.1139/b90-037.

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Six-week-old Pinus contorta seedlings were inoculated with spores of the western gall rust fungus Endocronartium harknessii. Of 660 seedlings inoculated, 174 showed early symptoms and were sampled for histological observation in the 7 weeks following inoculation. Pigmentation of epidermal cells was the first externally visible response to infection, generally occurring 14–28 days after inoculation. Developing symptoms were extremely variable, ranging from little or no visible response to severe necrosis. The appearance of external symptoms was largely due to changes occurring in underlying infected cortical cells such as the production of phenolic compounds, necrophylactic periderm, or necrotic tissue. Intercellular lignin deposition was observed in infected tissue and was thought to be associated with necrophylactic periderm formation. Suppression of normal exophylactic periderm development was evident in virtually all infected tissue zones. Infection of the vascular cambium occurred as early as 21 days after inoculation and resulted in the subsequent formation of distorted xylem tracheids typical of gall tissue.
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50

Angeles, Guillermo. "The Periderm of Flooded and Non·Flooded Ludwigia Octovalvis (Onagraceae)." IAWA Journal 13, no. 2 (1992): 195–200. http://dx.doi.org/10.1163/22941932-90001268.

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The periderm of Ludwigia octovalvis swells readilly when immersed in water. In non-flooded individuals the periderm is very compact, composed of typical brick-shaped, thick-walled phellem cells, without intercellular spaces, and a maximal radial length of 40 µm. The periderm of flooded individuals is very loose, with sausage-shaped, thin-walled phellem cells .reaching a maximum length of 280 µm and with long intercellular spaces between them. Phellem cells of flooded plants showed elongation very early in their differentiation from phellogen cells, forming slight protuberances which increased in size with increasing distance from the phellogen. The protuberances grew predominantly in the radial direction, centrifugally. Phellem cells of flooded plants just differentiated from the phellogen had dense cytoplasm and rounded nuclei with a more or less central position; those further away from the phellogen showed sparse cytoplasm and their nuclei were pulled towards either tip of the cells or laid against the cell walls.
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