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New Creative Relevant Search filters Coleoptile Stock Photos and Images  (206) Narrow your search: Vectors | Black & white | Cut Outs Page 1 of 3 Germinating wheat seeds with coleoptile and first leaf emerging Germinating wheat seeds with coleoptile and first leaf emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seeds-with-coleoptile-and-first-leaf-emerging-image7912681.html Corn seedling germination Corn seedling germinationhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-corn-seedling-germination-18518981.html FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-field-corngermination-germinating-kernel-with-primary-and-secondary-10537465.html Sir Francis Frank Darwin, F.R.S. (1848 -1925), a son of the British naturalist Charles Darwin, followed his father into botany. From Darwin and the Beagle by Alan Moorhead.. Francis Darwin worked with his father on experiments dealing with plant movement, specifically phototropism and they co-authored The Power of Movement in Plants (1880). Their experiments showed that the coleoptile of a young grass seedling directs its growth toward the light by comparing the responses of seedlings with covered and uncovered coleoptiles. These observations would later lead to the discovery of auxin.. . . . Sir Francis Frank Darwin, F.R.S. (1848 -1925), a son of the British naturalist Charles Darwin, followed his father into botany. From Darwin and the Beagle by Alan Moorhead.. Francis Darwin worked with his father on experiments dealing with plant movement, specifically phototropism and they co-authored The Power of Movement in Plants (1880). Their experiments showed that the coleoptile of a young grass seedling directs its growth toward the light by comparing the responses of seedlings with covered and uncovered coleoptiles. These observations would later lead to the discovery of auxin.. . . .https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/sir-francis-frank-darwin-frs-1848-1925-a-son-of-the-british-naturalist-charles-darwin-followed-his-father-into-botany-from-darwin-and-the-beagle-by-alan-moorhead-francis-darwin-worked-with-his-father-on-experiments-dealing-with-plant-movement-specifically-phototropism-and-they-co-authored-the-power-of-movement-in-plants-1880-their-experiments-showed-that-the-coleoptile-of-a-young-grass-seedling-directs-its-growth-toward-the-light-by-comparing-the-responses-of-seedlings-with-covered-and-uncovered-coleoptiles-these-observations-would-later-lead-to-the-discovery-of-auxin-image268794579.html Monocotyledon. showing hypogeal development in which the cotyledon remains invisible within the seed, underground. Education info graphic vector. Monocotyledon. showing hypogeal development in which the cotyledon remains invisible within the seed, underground. Education info graphic vector.https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/monocotyledon-showing-hypogeal-development-in-which-the-cotyledon-remains-invisible-within-the-seed-underground-education-info-graphic-vector-image235855294.html . The botany of crop plants; a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there becomes free. The coleoptile then opens. Jemma / yindicule jtamen. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Robbins, Wilfred William, 1884-1952. Philadelphia, P. Blakiston . The botany of crop plants; a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there becomes free. The coleoptile then opens. Jemma / yindicule jtamen. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Robbins, Wilfred William, 1884-1952. Philadelphia, P. Blakistonhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-botany-of-crop-plants-a-text-and-reference-book-botany-economic-hordeum-143-grows-under-the-lemma-and-palet-to-the-anterior-end-of-the-grain-and-there-becomes-free-the-coleoptile-then-opens-jemma-yindicule-jtamen-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-robbins-wilfred-william-1884-1952-philadelphia-p-blakiston-image234382221.html . The botany of crop plants : a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there becomes free. The coleoptile then opens ' Jemma / Jndicule 'j^ ^stamen. Fig. 52.—Diagrams showing the relative position of spikelets in barleys. A, six-rowed (Hordeum vulgare hexastichon); B, four-rowed barley (H. vul- gare pallidum); C, two-rowed barley (H. distichon); D, medium barley (H. vulgare intermedium). (After Broili.) and the first foliage leaf appears. In the germination of barley, the young leaves become twisted. This is c . The botany of crop plants : a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there becomes free. The coleoptile then opens ' Jemma / Jndicule 'j^ ^stamen. Fig. 52.—Diagrams showing the relative position of spikelets in barleys. A, six-rowed (Hordeum vulgare hexastichon); B, four-rowed barley (H. vul- gare pallidum); C, two-rowed barley (H. distichon); D, medium barley (H. vulgare intermedium). (After Broili.) and the first foliage leaf appears. In the germination of barley, the young leaves become twisted. This is chttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-botany-of-crop-plants-a-text-and-reference-book-botany-economic-hordeum-143-grows-under-the-lemma-and-palet-to-the-anterior-end-of-the-grain-and-there-becomes-free-the-coleoptile-then-opens-jemma-jndicule-j-stamen-fig-52diagrams-showing-the-relative-position-of-spikelets-in-barleys-a-six-rowed-hordeum-vulgare-hexastichon-b-four-rowed-barley-h-vul-gare-pallidum-c-two-rowed-barley-h-distichon-d-medium-barley-h-vulgare-intermedium-after-broili-and-the-first-foliage-leaf-appears-in-the-germination-of-barley-the-young-leaves-become-twisted-this-is-c-image216371901.html Wheat. Germinating. Showing shoots and roots after a soaking in water for 48 hours. Wheat. Germinating. Showing shoots and roots after a soaking in water for 48 hours.https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-wheat-germinating-showing-shoots-and-roots-after-a-soaking-in-water-72571648.html Cross section emerging corn Zea coleoptile magnification 40x Cross section emerging corn Zea coleoptile magnification 40xhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-cross-section-emerging-corn-zea-coleoptile-magnification-40x-56084348.html Germinating maize or corn seed, Zea mays, with radicle, root and coleoptile growth developing Germinating maize or corn seed, Zea mays, with radicle, root and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-maize-or-corn-seed-zea-mays-with-radicle-root-and-coleoptile-106472028.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-52301382.html showing hypogeal development in which the cotyledon remains invisible within the seed, underground. The visible part is the first true leaf produced f showing hypogeal development in which the cotyledon remains invisible within the seed, underground. The visible part is the first true leaf produced fhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-showing-hypogeal-development-in-which-the-cotyledon-remains-invisible-135199558.html monocotyledon monocotyledonhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/monocotyledon-image227467257.html Germinating wheat seeds with coleoptile and first leaf emerging Germinating wheat seeds with coleoptile and first leaf emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seeds-with-coleoptile-and-first-leaf-emerging-image278920400.html Monocot dicot development comparison Monocot dicot development comparisonhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-monocot-dicot-development-comparison-18522673.html Wheat plant germinating with coleoptile and first leaf emerged Wheat plant germinating with coleoptile and first leaf emergedhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/wheat-plant-germinating-with-coleoptile-and-first-leaf-emerged-image7912843.html FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/field-corngermination-germinating-kernel-with-primary-and-secondary-roots-root-hairs-and-coleoptile-image275583690.html Upside down seed shows gravitropism - the root curves to grow down and the shoot curves upward (see description below) Upside down seed shows gravitropism - the root curves to grow down and the shoot curves upward (see description below)https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-upside-down-seed-shows-gravitropism-the-root-curves-to-grow-down-and-31214287.html . Botany of the living plant. Botany; Plants. GROWTH, IRRITABILITY AND MOVEMENT 151 chemical nature of this growth-promoting hormone, which is known as Auxin, has been obtained, and a number of other substances, natural and synthetic, have been found to stimulate the growth of the coleoptile much like Auxin itself. The man- ner in which cell-elongation is affected is not yet clear, though there is evidence that the hormone increases the plasticity of the cell- walls (seep. 142). Similar experiments to those described for the coleoptile Fig. 93. have been carried out with shoots of Curvatures i . Botany of the living plant. Botany; Plants. GROWTH, IRRITABILITY AND MOVEMENT 151 chemical nature of this growth-promoting hormone, which is known as Auxin, has been obtained, and a number of other substances, natural and synthetic, have been found to stimulate the growth of the coleoptile much like Auxin itself. The man- ner in which cell-elongation is affected is not yet clear, though there is evidence that the hormone increases the plasticity of the cell- walls (seep. 142). Similar experiments to those described for the coleoptile Fig. 93. have been carried out with shoots of Curvatures ihttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/botany-of-the-living-plant-botany-plants-growth-irritability-and-movement-151-chemical-nature-of-this-growth-promoting-hormone-which-is-known-as-auxin-has-been-obtained-and-a-number-of-other-substances-natural-and-synthetic-have-been-found-to-stimulate-the-growth-of-the-coleoptile-much-like-auxin-itself-the-man-ner-in-which-cell-elongation-is-affected-is-not-yet-clear-though-there-is-evidence-that-the-hormone-increases-the-plasticity-of-the-cell-walls-seep-142-similar-experiments-to-those-described-for-the-coleoptile-fig-93-have-been-carried-out-with-shoots-of-curvatures-i-image234362629.html . Heredity and evolution in plants. Heredity; Plants. 224 HEREDITY AND EVOLUTION IN PLANTS senting 12 tribes, demonstrated the presence of the rudi- mentary cotyledon (epiblast) in 29 of the genera, repre-. FiG. 106.—Diagram of longitudinal sections of grass-embryos (Gram- ineas) to illustrate the rudimentary cotyledon {epiblast). A-C, E-G, redrawn from J. M. Coulter, after Bruns; D, from nature. A, Zizania acflatica; B, Leersia clandestina; C, Leptochloa arabica; D, Triticum vtd- gare; E, Spartina cynosuroides; F, Trilicum vulgare; G, Zea Mays; i, scutellum; c, coleoptile; ii, epiblast. senti . Heredity and evolution in plants. Heredity; Plants. 224 HEREDITY AND EVOLUTION IN PLANTS senting 12 tribes, demonstrated the presence of the rudi- mentary cotyledon (epiblast) in 29 of the genera, repre-. FiG. 106.—Diagram of longitudinal sections of grass-embryos (Gram- ineas) to illustrate the rudimentary cotyledon {epiblast). A-C, E-G, redrawn from J. M. Coulter, after Bruns; D, from nature. A, Zizania acflatica; B, Leersia clandestina; C, Leptochloa arabica; D, Triticum vtd- gare; E, Spartina cynosuroides; F, Trilicum vulgare; G, Zea Mays; i, scutellum; c, coleoptile; ii, epiblast. sentihttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/heredity-and-evolution-in-plants-heredity-plants-224-heredity-and-evolution-in-plants-senting-12-tribes-demonstrated-the-presence-of-the-rudi-mentary-cotyledon-epiblast-in-29-of-the-genera-repre-fig-106diagram-of-longitudinal-sections-of-grass-embryos-gram-ineas-to-illustrate-the-rudimentary-cotyledon-epiblast-a-c-e-g-redrawn-from-j-m-coulter-after-bruns-d-from-nature-a-zizania-acflatica-b-leersia-clandestina-c-leptochloa-arabica-d-triticum-vtd-gare-e-spartina-cynosuroides-f-trilicum-vulgare-g-zea-mays-i-scutellum-c-coleoptile-ii-epiblast-senti-image216421079.html Wheat. Germinating. Showing shoots and roots after a soaking in water for 48 hours. Wheat. Germinating. Showing shoots and roots after a soaking in water for 48 hours.https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-wheat-germinating-showing-shoots-and-roots-after-a-soaking-in-water-72571658.html Cross section emerging corn Zea coleoptile magnification 40x Cross section emerging corn Zea coleoptile magnification 40xhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/cross-section-emerging-corn-zea-coleoptile-magnification-40x-image282465310.html Germinating maize or corn seed, Zea mays, with radicle, root and coleoptile growth developing Germinating maize or corn seed, Zea mays, with radicle, root and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-maize-or-corn-seed-zea-mays-with-radicle-root-and-coleoptile-growth-developing-image278228168.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315846.html Wheat plant germinating with coleoptile and first leaf emerged Wheat plant germinating with coleoptile and first leaf emergedhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/wheat-plant-germinating-with-coleoptile-and-first-leaf-emerged-image278157562.html FIELD CORN / GERMINATING KERNEL SHOWING PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN / GERMINATING KERNEL SHOWING PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/field-corn-germinating-kernel-showing-primary-and-secondary-roots-root-hairs-and-coleoptile-image281320495.html Emerging barley seedling coleoptile with exudation droplet but no leaf Emerging barley seedling coleoptile with exudation droplet but no leafhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/emerging-barley-seedling-coleoptile-with-exudation-droplet-but-no-image7911526.html Sideways seed shows gravitropism - the root curves to grow down and the shoot curves upward (see description below) Sideways seed shows gravitropism - the root curves to grow down and the shoot curves upward (see description below)https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-sideways-seed-shows-gravitropism-the-root-curves-to-grow-down-and-31215401.html . The botany of crop plants; a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there l)ecomes free. The coleoptile then opens. Jemma / JodieuU. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Robbins, Wilfred William, 1884-1952. Philadelphia, P. Blakiston's Son & Co . The botany of crop plants; a text and reference book. Botany, Economic. HORDEUM 143 grows under the lemma and palet to the anterior end of the grain and there l)ecomes free. The coleoptile then opens. Jemma / JodieuU. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Robbins, Wilfred William, 1884-1952. Philadelphia, P. Blakiston's Son & Cohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-botany-of-crop-plants-a-text-and-reference-book-botany-economic-hordeum-143-grows-under-the-lemma-and-palet-to-the-anterior-end-of-the-grain-and-there-lecomes-free-the-coleoptile-then-opens-jemma-jodieuu-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-robbins-wilfred-william-1884-1952-philadelphia-p-blakistons-son-amp-co-image234394770.html Cross section emerging corn Zea coleoptile magnification 100x Cross section emerging corn Zea coleoptile magnification 100xhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-cross-section-emerging-corn-zea-coleoptile-magnification-100x-56084354.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image277047582.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315853.html FIELD CORN / GERMINATING KERNEL SHOWING PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN / GERMINATING KERNEL SHOWING PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-field-corn-germinating-kernel-showing-primary-and-secondary-roots-10537463.html Emerging barley seedling coleoptile with exudation droplet but no leaf Emerging barley seedling coleoptile with exudation droplet but no leafhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/emerging-barley-seedling-coleoptile-with-exudation-droplet-but-no-leaf-image279599146.html Corn seeds demonstrating gravitropism (geotropism). In each seed orientation the root is growing down and the shoot upward. Corn seeds demonstrating gravitropism (geotropism). In each seed orientation the root is growing down and the shoot upward.https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-corn-seeds-demonstrating-gravitropism-geotropism-in-each-seed-orientation-31214267.html Winter wild oat Avena sterilis seedling with first leaf emerging from coleoptile Winter wild oat Avena sterilis seedling with first leaf emerging from coleoptilehttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-winter-wild-oat-avena-sterilis-seedling-with-first-leaf-emerging-from-10333002.html Organography of plants, especially of the archegoniatae and spermaphyta . are independentleaves. The scutellum con-tains at its point of insertionon the internode, one vascularbundle which branches in thescutellum ; the coleoptile con-tains two of these which arederived from the node K.The internode, Ale, has aquite different structure fromthe later internodes. It has,not like them scattered vas-cular bundles, but a vascularcylinder enclosed by an en-dodermis. In other grassesthe anatomical relationshipscorrespond, on the other hand,with those of Carex. Zizania aquatica. InFig. 281, II, we hav Organography of plants, especially of the archegoniatae and spermaphyta . are independentleaves. The scutellum con-tains at its point of insertionon the internode, one vascularbundle which branches in thescutellum ; the coleoptile con-tains two of these which arederived from the node K.The internode, Ale, has aquite different structure fromthe later internodes. It has,not like them scattered vas-cular bundles, but a vascularcylinder enclosed by an en-dodermis. In other grassesthe anatomical relationshipscorrespond, on the other hand,with those of Carex. Zizania aquatica. InFig. 281, II, we havhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/organography-of-plants-especially-of-the-archegoniatae-and-spermaphyta-are-independentleaves-the-scutellum-con-tains-at-its-point-of-insertionon-the-internode-one-vascularbundle-which-branches-in-thescutellum-the-coleoptile-con-tains-two-of-these-which-arederived-from-the-node-kthe-internode-ale-has-aquite-different-structure-fromthe-later-internodes-it-hasnot-like-them-scattered-vas-cular-bundles-but-a-vascularcylinder-enclosed-by-an-en-dodermis-in-other-grassesthe-anatomical-relationshipscorrespond-on-the-other-handwith-those-of-carex-zizania-aquatica-infig-281-ii-we-hav-image340147820.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472029.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315880.html FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-field-corngermination-germinating-kernel-with-primary-and-secondary-10537466.html Corn, Zea mays, seedling recently germinated. Corn, Zea mays, seedling recently germinated.https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-corn-zea-mays-seedling-recently-germinated-31212950.html Winter wild oat Avena sterilis seedling with first leaf emerging from coleoptile Winter wild oat Avena sterilis seedling with first leaf emerging from coleoptilehttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/winter-wild-oat-avena-sterilis-seedling-with-first-leaf-emerging-from-coleoptile-image278471193.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors markedly increases the response of oat coleoptile sections to lAA, though Schneider (1941) reported that first internodes were almost insensitive to sucrose. A study of this point, conducted with both coleoptiles and internodes, demonstrated beyond any doubt that the growth of first internodes as well as that of coleoptiles is strongly increased by sucrose i . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors markedly increases the response of oat coleoptile sections to lAA, though Schneider (1941) reported that first internodes were almost insensitive to sucrose. A study of this point, conducted with both coleoptiles and internodes, demonstrated beyond any doubt that the growth of first internodes as well as that of coleoptiles is strongly increased by sucrose ihttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-investigation-of-natural-auxins-and-growth-inhibitors-markedly-increases-the-response-of-oat-coleoptile-sections-to-laa-though-schneider-1941-reported-that-first-internodes-were-almost-insensitive-to-sucrose-a-study-of-this-point-conducted-with-both-coleoptiles-and-internodes-demonstrated-beyond-any-doubt-that-the-growth-of-first-internodes-as-well-as-that-of-coleoptiles-is-strongly-increased-by-sucrose-i-image234988591.html Emerging wheat seedlings with dew droplets still within their coleoptile sheaths Emerging wheat seedlings with dew droplets still within their coleoptile sheathshttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-emerging-wheat-seedlings-with-dew-droplets-still-within-their-coleoptile-13215455.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image277140977.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315892.html FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILE FIELD CORN/GERMINATION GERMINATING KERNEL WITH PRIMARY AND SECONDARY ROOTS, ROOT HAIRS AND COLEOPTILEhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/field-corngermination-germinating-kernel-with-primary-and-secondary-roots-root-hairs-and-coleoptile-image277956792.html Corn, Zea mays, seedling recently germinated Corn, Zea mays, seedling recently germinatedhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-corn-zea-mays-seedling-recently-germinated-31210007.html Organography of plants, especially of the archegoniatae and spermaphyta . g. 282). 2. The scutellum is the coty-ledon, and the epiblast which lies overagainst it, but is not present in all grasses, is an arrested second leaf, and the coleoptile is the third leaf. This view is supported by the following:— {a) Between the coleoptile and the scutellum, there is in many grassesa strongly developed internode. {b) In the axil of the coleoptile an axillary bud is often found. {c) The basal part of the scutellum in many grasses, for example Oryza(Fig. 281, V), Leersia, and others (Fig. 281, I) develop Organography of plants, especially of the archegoniatae and spermaphyta . g. 282). 2. The scutellum is the coty-ledon, and the epiblast which lies overagainst it, but is not present in all grasses, is an arrested second leaf, and the coleoptile is the third leaf. This view is supported by the following:— {a) Between the coleoptile and the scutellum, there is in many grassesa strongly developed internode. {b) In the axil of the coleoptile an axillary bud is often found. {c) The basal part of the scutellum in many grasses, for example Oryza(Fig. 281, V), Leersia, and others (Fig. 281, I) develophttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/organography-of-plants-especially-of-the-archegoniatae-and-spermaphyta-g-282-2-the-scutellum-is-the-coty-ledon-and-the-epiblast-which-lies-overagainst-it-but-is-not-present-in-all-grasses-is-an-arrested-second-leaf-and-the-coleoptile-is-the-third-leaf-this-view-is-supported-by-the-following-a-between-the-coleoptile-and-the-scutellum-there-is-in-many-grassesa-strongly-developed-internode-b-in-the-axil-of-the-coleoptile-an-axillary-bud-is-often-found-c-the-basal-part-of-the-scutellum-in-many-grasses-for-example-oryzafig-281-v-leersia-and-others-fig-281-i-develop-image340148822.html Emerging wheat seedlings with dew droplets still within their coleoptile sheaths Emerging wheat seedlings with dew droplets still within their coleoptile sheathshttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/emerging-wheat-seedlings-with-dew-droplets-still-within-their-coleoptile-sheaths-image277901072.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472022.html Germinating wheat seed with radicle well developed and coleoptile emerging Germinating wheat seed with radicle well developed and coleoptile emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seed-with-radicle-well-developed-and-coleoptile-emerging-image281229902.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315886.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Metabolism and mode of action respiration diminishes however with increasing external osmotic concentra- tion and disappears at an external osmotic concentration of 0-4 M in which elongation is reduced to a low value. These results parallel those obtained with Jerusalem artichoke storage tissue (Bonner, Bandurski, and Millerd, 1953). It has been concluded that the Avena coleoptile is at all times essentially in . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Metabolism and mode of action respiration diminishes however with increasing external osmotic concentra- tion and disappears at an external osmotic concentration of 0-4 M in which elongation is reduced to a low value. These results parallel those obtained with Jerusalem artichoke storage tissue (Bonner, Bandurski, and Millerd, 1953). It has been concluded that the Avena coleoptile is at all times essentially inhttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-metabolism-and-mode-of-action-respiration-diminishes-however-with-increasing-external-osmotic-concentra-tion-and-disappears-at-an-external-osmotic-concentration-of-0-4-m-in-which-elongation-is-reduced-to-a-low-value-these-results-parallel-those-obtained-with-jerusalem-artichoke-storage-tissue-bonner-bandurski-and-millerd-1953-it-has-been-concluded-that-the-avena-coleoptile-is-at-all-times-essentially-in-image235005071.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image276592738.html Germinating wheat seed with radicle well developed and coleoptile emerging Germinating wheat seed with radicle well developed and coleoptile emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seed-with-radicle-well-developed-and-coleoptile-image5289816.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315874.html Germinating wheat seed with root (radicle), coleorhiza, and root hairs and coleoptile just emerging Germinating wheat seed with root (radicle), coleorhiza, and root hairs and coleoptile just emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seed-with-root-radicle-coleorhiza-and-root-hairs-and-coleoptile-just-emerging-image242011582.html Germinating wheat seed with root (radicle), coleorhiza, and root hairs and coleoptile just emerging Germinating wheat seed with root (radicle), coleorhiza, and root hairs and coleoptile just emerginghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-wheat-seed-with-root-radicle-coleorhiza-and-root-hairs-and-coleoptile-just-emerging-image242011590.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874025.html . The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 302 KENNETH V. THIMANN addition of pyruvate (which is very active when pure), of citrate for young plants only, and of acetate. These acids active in growth are those of the Krebs cycle. The importance of this cycle in respiration is well known, and recently J. Bonner (1948) has made it probable that the same or a similar cycle occurs in the respiration of coleoptile tissue. The experiments above, and several others, make it clear that malate and other acids of the cycle actually participate in the normal growth process. 100 . The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 302 KENNETH V. THIMANN addition of pyruvate (which is very active when pure), of citrate for young plants only, and of acetate. These acids active in growth are those of the Krebs cycle. The importance of this cycle in respiration is well known, and recently J. Bonner (1948) has made it probable that the same or a similar cycle occurs in the respiration of coleoptile tissue. The experiments above, and several others, make it clear that malate and other acids of the cycle actually participate in the normal growth process. 100https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-biological-bulletin-biology-zoology-biology-marine-biology-302-kenneth-v-thimann-addition-of-pyruvate-which-is-very-active-when-pure-of-citrate-for-young-plants-only-and-of-acetate-these-acids-active-in-growth-are-those-of-the-krebs-cycle-the-importance-of-this-cycle-in-respiration-is-well-known-and-recently-j-bonner-1948-has-made-it-probable-that-the-same-or-a-similar-cycle-occurs-in-the-respiration-of-coleoptile-tissue-the-experiments-above-and-several-others-make-it-clear-that-malate-and-other-acids-of-the-cycle-actually-participate-in-the-normal-growth-process-100-image234667134.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image279501378.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315861.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image280978589.html . Auxins and plant growth. Auxin; Plant growth promoting substances. 128 Fundamentals of Auxin Action An interesting difference in sensitivity of the respiratory systems of monocots and dicots has been demonstrated by Kelly and Avery (1949). They found that respiration of pea stems is stimulated by concentrations of auxin over one hundred times more dilute than those needed to stimulate respiration in the Avena coleoptile. The greater respiratory sensitivity of the pea as shown in figure 57 is strongly reminiscent of the greater herbicidal sensitivity of dicots in comparison with monocots. c o . Auxins and plant growth. Auxin; Plant growth promoting substances. 128 Fundamentals of Auxin Action An interesting difference in sensitivity of the respiratory systems of monocots and dicots has been demonstrated by Kelly and Avery (1949). They found that respiration of pea stems is stimulated by concentrations of auxin over one hundred times more dilute than those needed to stimulate respiration in the Avena coleoptile. The greater respiratory sensitivity of the pea as shown in figure 57 is strongly reminiscent of the greater herbicidal sensitivity of dicots in comparison with monocots. c ohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/auxins-and-plant-growth-auxin-plant-growth-promoting-substances-128-fundamentals-of-auxin-action-an-interesting-difference-in-sensitivity-of-the-respiratory-systems-of-monocots-and-dicots-has-been-demonstrated-by-kelly-and-avery-1949-they-found-that-respiration-of-pea-stems-is-stimulated-by-concentrations-of-auxin-over-one-hundred-times-more-dilute-than-those-needed-to-stimulate-respiration-in-the-avena-coleoptile-the-greater-respiratory-sensitivity-of-the-pea-as-shown-in-figure-57-is-strongly-reminiscent-of-the-greater-herbicidal-sensitivity-of-dicots-in-comparison-with-monocots-c-o-image235287633.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472025.html microscopy micrograph plant tissue, corn embryo microscopy micrograph plant tissue, corn embryohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-microscopy-micrograph-plant-tissue-corn-embryo-50315868.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874004.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). The kinetics of auxin-induced growth nature of the substrate concentration growth rate relation suggests that the coleoptile possesses spots which can interact with auxin. We do not find out by our treatment where the spots are or what they do. It is necessary to try to find out what the spots are by other types of experiments. We have approached this problem with the aid of C^^ carboxyl-labelled 2:4-D of high . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). The kinetics of auxin-induced growth nature of the substrate concentration growth rate relation suggests that the coleoptile possesses spots which can interact with auxin. We do not find out by our treatment where the spots are or what they do. It is necessary to try to find out what the spots are by other types of experiments. We have approached this problem with the aid of C^^ carboxyl-labelled 2:4-D of high https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-the-kinetics-of-auxin-induced-growth-nature-of-the-substrate-concentration-growth-rate-relation-suggests-that-the-coleoptile-possesses-spots-which-can-interact-with-auxin-we-do-not-find-out-by-our-treatment-where-the-spots-are-or-what-they-do-it-is-necessary-to-try-to-find-out-what-the-spots-are-by-other-types-of-experiments-we-have-approached-this-problem-with-the-aid-of-c-carboxyl-labelled-24-d-of-high-image235004772.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472027.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874002.html . The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 298 KENNETH V. THIMANN GROWTH INHIBITION BY IODOACETATE The growth is reduced or prevented by inhibitors of dehydrogenases. The effect of iodoacetate was studied in detail by Commoner and Thimann (1941), who showed that growth of coleoptile sections is strongly inhibited by this substance. However, concentrations of the inhibitor which reduce growth practically to zero have only a very small effect on respiration. (The data on respiration are in excel- lent agreement with the later measurements of J. Bonner, 1948). Here agai . The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 298 KENNETH V. THIMANN GROWTH INHIBITION BY IODOACETATE The growth is reduced or prevented by inhibitors of dehydrogenases. The effect of iodoacetate was studied in detail by Commoner and Thimann (1941), who showed that growth of coleoptile sections is strongly inhibited by this substance. However, concentrations of the inhibitor which reduce growth practically to zero have only a very small effect on respiration. (The data on respiration are in excel- lent agreement with the later measurements of J. Bonner, 1948). Here agaihttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-biological-bulletin-biology-zoology-biology-marine-biology-298-kenneth-v-thimann-growth-inhibition-by-iodoacetate-the-growth-is-reduced-or-prevented-by-inhibitors-of-dehydrogenases-the-effect-of-iodoacetate-was-studied-in-detail-by-commoner-and-thimann-1941-who-showed-that-growth-of-coleoptile-sections-is-strongly-inhibited-by-this-substance-however-concentrations-of-the-inhibitor-which-reduce-growth-practically-to-zero-have-only-a-very-small-effect-on-respiration-the-data-on-respiration-are-in-excel-lent-agreement-with-the-later-measurements-of-j-bonner-1948-here-agai-image234667186.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image284294923.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874006.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors horizontal shaker. To be able to section the coleoptiles and internodes accurately, we used Thimann's 'guillotine' {Figure 9), an improvement over the original Van der Weij's 'coleoptile microtome' (1932). The primary leaf was always left included in the coleoptile. This procedure simplifies the test without impairing its sensitivity or reliability. The firs . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors horizontal shaker. To be able to section the coleoptiles and internodes accurately, we used Thimann's 'guillotine' {Figure 9), an improvement over the original Van der Weij's 'coleoptile microtome' (1932). The primary leaf was always left included in the coleoptile. This procedure simplifies the test without impairing its sensitivity or reliability. The firshttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-investigation-of-natural-auxins-and-growth-inhibitors-horizontal-shaker-to-be-able-to-section-the-coleoptiles-and-internodes-accurately-we-used-thimanns-guillotine-figure-9-an-improvement-over-the-original-van-der-weijs-coleoptile-microtome-1932-the-primary-leaf-was-always-left-included-in-the-coleoptile-this-procedure-simplifies-the-test-without-impairing-its-sensitivity-or-reliability-the-firs-image234988661.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472023.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image279012441.html Smithsonian miscellaneous collections . coleoptile. The spectrum utilized was obtained from a concave grating. Thewave-length intervals throughout the spectrum are uniform. The ^ Numbers in parentheses refer to list of literature cited at end of paper.Smithsonian Miscellaneous Collections, Vol. 95, No. 9 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 grating was not of the highest quality, but precautions against spuriouseffects from scattered Hght were taken by employing filters of coloredcellophane. Although the idea of forces arising from a wave-length gradientmay appear strange, they are to Smithsonian miscellaneous collections . coleoptile. The spectrum utilized was obtained from a concave grating. Thewave-length intervals throughout the spectrum are uniform. The ^ Numbers in parentheses refer to list of literature cited at end of paper.Smithsonian Miscellaneous Collections, Vol. 95, No. 9 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 grating was not of the highest quality, but precautions against spuriouseffects from scattered Hght were taken by employing filters of coloredcellophane. Although the idea of forces arising from a wave-length gradientmay appear strange, they are tohttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/smithsonian-miscellaneous-collections-coleoptile-the-spectrum-utilized-was-obtained-from-a-concave-grating-thewave-length-intervals-throughout-the-spectrum-are-uniform-the-numbers-in-parentheses-refer-to-list-of-literature-cited-at-end-of-papersmithsonian-miscellaneous-collections-vol-95-no-9-smithsonian-miscellaneous-collections-vol-95-grating-was-not-of-the-highest-quality-but-precautions-against-spuriouseffects-from-scattered-hght-were-taken-by-employing-filters-of-coloredcellophane-although-the-idea-of-forces-arising-from-a-wave-length-gradientmay-appear-strange-they-are-to-image338495102.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image278466684.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image283320429.html . Auxins and plant growth. Auxin; Plant growth promoting substances. CH,C NH, H,0. CHgCOOH ^ NH3* indoleacetic acid indoleacetamide Early work on the movement of auxins in the Avena coleoptile demonstrated that no particular type of tissue was exclusively involved. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Leopold, A. Carl (Aldo Carl), 1919-. Berkeley, University of California Press . Auxins and plant growth. Auxin; Plant growth promoting substances. CH,C NH, H,0. CHgCOOH ^ NH3* indoleacetic acid indoleacetamide Early work on the movement of auxins in the Avena coleoptile demonstrated that no particular type of tissue was exclusively involved. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Leopold, A. Carl (Aldo Carl), 1919-. Berkeley, University of California Presshttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/auxins-and-plant-growth-auxin-plant-growth-promoting-substances-chc-nh-h0-chgcooh-nh3-indoleacetic-acid-indoleacetamide-early-work-on-the-movement-of-auxins-in-the-avena-coleoptile-demonstrated-that-no-particular-type-of-tissue-was-exclusively-involved-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-leopold-a-carl-aldo-carl-1919-berkeley-university-of-california-press-image235293804.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472020.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image278931634.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Applications of kinetics to auxin-induced growth consistent results. There are, however, other experimental facts which do not appear to us to be capable of such treatment. A simple example is the fact that the apparent A'^ of auxin in the coleoptile system is not constant as between one lot of seeds and another. We have found variations of two- to four-fold of the values of Kg in successive yearly harvests oi^ . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Applications of kinetics to auxin-induced growth consistent results. There are, however, other experimental facts which do not appear to us to be capable of such treatment. A simple example is the fact that the apparent A'^ of auxin in the coleoptile system is not constant as between one lot of seeds and another. We have found variations of two- to four-fold of the values of Kg in successive yearly harvests oi^https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-applications-of-kinetics-to-auxin-induced-growth-consistent-results-there-are-however-other-experimental-facts-which-do-not-appear-to-us-to-be-capable-of-such-treatment-a-simple-example-is-the-fact-that-the-apparent-a-of-auxin-in-the-coleoptile-system-is-not-constant-as-between-one-lot-of-seeds-and-another-we-have-found-variations-of-two-to-four-fold-of-the-values-of-kg-in-successive-yearly-harvests-oi-image235004797.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image283477151.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874000.html . Auxins and plant growth. Auxin; Plant growth promoting substances. Occurrence and Role of Growth Hormones 61 that of the etiolated Avena seedling carried out by Thimann (1934). Using a solvent extraction technique, he demonstrated an auxin gra- dient through the plant with by far the highest concentration occur- ring at the coleoptile tip and a lesser concentration at the root tip. A sagging gradient was found to lie between these two peaks (figure 28). It is evident that the coleoptile apex and the root apex are the two primary loci of auxin formation in the etiolated oat seedling and that . Auxins and plant growth. Auxin; Plant growth promoting substances. Occurrence and Role of Growth Hormones 61 that of the etiolated Avena seedling carried out by Thimann (1934). Using a solvent extraction technique, he demonstrated an auxin gra- dient through the plant with by far the highest concentration occur- ring at the coleoptile tip and a lesser concentration at the root tip. A sagging gradient was found to lie between these two peaks (figure 28). It is evident that the coleoptile apex and the root apex are the two primary loci of auxin formation in the etiolated oat seedling and that https://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/auxins-and-plant-growth-auxin-plant-growth-promoting-substances-occurrence-and-role-of-growth-hormones-61-that-of-the-etiolated-avena-seedling-carried-out-by-thimann-1934-using-a-solvent-extraction-technique-he-demonstrated-an-auxin-gra-dient-through-the-plant-with-by-far-the-highest-concentration-occur-ring-at-the-coleoptile-tip-and-a-lesser-concentration-at-the-root-tip-a-sagging-gradient-was-found-to-lie-between-these-two-peaks-figure-28-it-is-evident-that-the-coleoptile-apex-and-the-root-apex-are-the-two-primary-loci-of-auxin-formation-in-the-etiolated-oat-seedling-and-that-image235293932.html Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing Germinating seed of winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-germinating-seed-of-winter-wheat-triticum-aestivum-with-radicle-root-106472030.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image279480967.html . Biologiske meddelelser. Biology. Det Kgl. Danske Videnskabernes Selskab. ' Biologiske Meddelelser, III, 8. STUDIES ON THE PATH OP TRANSMISSION OF PHOTOTROPIC AND GEOTROPIC STIMULI IN THE COLEOPTILE OF AVENà BY HELEN ALICE PURDY. KÃBENHAVN hovedkommissionær: ANDR. FRED. HÃST & SÃN. kgl. hof-boghandel BIANCO LUNOS BOGTRYKKERI 1921. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Danske videnskabernes selskab, Copenhage . Biologiske meddelelser. Biology. Det Kgl. Danske Videnskabernes Selskab. ' Biologiske Meddelelser, III, 8. STUDIES ON THE PATH OP TRANSMISSION OF PHOTOTROPIC AND GEOTROPIC STIMULI IN THE COLEOPTILE OF AVENà BY HELEN ALICE PURDY. KÃBENHAVN hovedkommissionær: ANDR. FRED. HÃST & SÃN. kgl. hof-boghandel BIANCO LUNOS BOGTRYKKERI 1921. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Danske videnskabernes selskab, Copenhagehttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/biologiske-meddelelser-biology-det-kgl-danske-videnskabernes-selskab-biologiske-meddelelser-iii-8-studies-on-the-path-op-transmission-of-phototropic-and-geotropic-stimuli-in-the-coleoptile-of-aven-by-helen-alice-purdy-kbenhavn-hovedkommissionr-andr-fred-hst-amp-sn-kgl-hof-boghandel-bianco-lunos-bogtrykkeri-1921-please-note-that-these-images-are-extracted-from-scanned-page-images-that-may-have-been-digitally-enhanced-for-readability-coloration-and-appearance-of-these-illustrations-may-not-perfectly-resemble-the-original-work-danske-videnskabernes-selskab-copenhage-image234609131.html Wheat seeds germinating in a glass sided tank showing root and aerial development Wheat seeds germinating in a glass sided tank showing root and aerial developmenthttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/wheat-seeds-germinating-in-a-glass-sided-tank-showing-root-and-aerial-development-image278826133.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image276527556.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors THE BIO-ASSAY Since the primary aim of our study is to separate and identify biologically active substances, it is important to have a sensitive, reliable, and easy-to- perform bio-assay. The results of a search for a suitable plant material! l^d us to conclude that the coleoptile and the first internode of the oat seedling were suitable test objects. The va . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Investigation of natural auxins and growth inhibitors THE BIO-ASSAY Since the primary aim of our study is to separate and identify biologically active substances, it is important to have a sensitive, reliable, and easy-to- perform bio-assay. The results of a search for a suitable plant material! l^d us to conclude that the coleoptile and the first internode of the oat seedling were suitable test objects. The vahttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-investigation-of-natural-auxins-and-growth-inhibitors-the-bio-assay-since-the-primary-aim-of-our-study-is-to-separate-and-identify-biologically-active-substances-it-is-important-to-have-a-sensitive-reliable-and-easy-to-perform-bio-assay-the-results-of-a-search-for-a-suitable-plant-material!-ld-us-to-conclude-that-the-coleoptile-and-the-first-internode-of-the-oat-seedling-were-suitable-test-objects-the-va-image234988730.html Wheat seeds germinating in a glass sided tank showing root and aerial development Wheat seeds germinating in a glass sided tank showing root and aerial developmenthttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-wheat-seeds-germinating-in-a-glass-sided-tank-showing-root-and-aerial-132361358.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874003.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-root-hairs-and-coleoptile-growth-developing-image281494368.html . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Metabolism and mode of action internal diffusion pressure deficit. It has long been known that sugars or potassium salts act as cofactors in auxin-induced elongation of coleoptile sections. The role of these substances is apparently in part an osmotic one. They contribute to the maintenance of internal osmotic concentration. lAA af 1t , Figure 7. The presence of auxin (lAA, 5 mgjl.) is without effect on the le . The chemistry and mode of action of plant growth substances; proceedings of a symposium held at Wye College, University of London, July 1955. Plant regulators; Auxin; Growth (Plants). Metabolism and mode of action internal diffusion pressure deficit. It has long been known that sugars or potassium salts act as cofactors in auxin-induced elongation of coleoptile sections. The role of these substances is apparently in part an osmotic one. They contribute to the maintenance of internal osmotic concentration. lAA af 1t , Figure 7. The presence of auxin (lAA, 5 mgjl.) is without effect on the lehttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/the-chemistry-and-mode-of-action-of-plant-growth-substances-proceedings-of-a-symposium-held-at-wye-college-university-of-london-july-1955-plant-regulators-auxin-growth-plants-metabolism-and-mode-of-action-internal-diffusion-pressure-deficit-it-has-long-been-known-that-sugars-or-potassium-salts-act-as-cofactors-in-auxin-induced-elongation-of-coleoptile-sections-the-role-of-these-substances-is-apparently-in-part-an-osmotic-one-they-contribute-to-the-maintenance-of-internal-osmotic-concentration-laa-af-1t-figure-7-the-presence-of-auxin-laa-5-mgjl-is-without-effect-on-the-le-image235005077.html Wheat seeds germinating in a glass sided tank showing root and aerial development Wheat seeds germinating in a glass sided tank showing root and aerial developmenthttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/wheat-seeds-germinating-in-a-glass-sided-tank-showing-root-and-aerial-development-image280668212.html A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developing A germinating seed if winter wheat, Triticum aestivum, with radicle, root hairs and coleoptile growth developinghttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/stock-photo-a-germinating-seed-if-winter-wheat-triticum-aestivum-with-radicle-102874026.html Shoots of young wheat crop emerging above the soil and with exudation droplets Shoots of young wheat crop emerging above the soil and with exudation dropletshttps://www.alamy.com/licenses-and-pricing/?v=1https://www.alamy.com/shoots-of-young-wheat-crop-emerging-above-the-soil-and-with-exudation-droplets-image280244212.html Next page Recent searches: Search Results for Coleoptile Stock Photos and Images  (206) Page 1 of 3 123