Apical applications of 0.2 micrograms N('6)-benzyladenine (BA), a synthetic cytokinin, or 5 micrograms gibberellic acid (GA) significantly enhanced hypocotyl elongation in intact dwarf watermelon seedlings. Accompanying the increase in hypocotyl length was increased expansion of the cotyledons and inhibition of root growth. A study on dry matter partitioning indicated that both hormones caused a preferential mobilization of metabolites from the cotyledons to the hypocotyl at an expense to roots. However, in comparison to untreated or GA-treated seedlings, BA decreased total translocation of metabolites out of the cotyledons. Hormonal effects on water potential of cotyledons and hypocotyls were determined by allowing organs to equilibrate for 2 h in serial concentrations of polyethylene glycol 4000. Osmotic potentials were determined with a dewpoint microvoltmeter. Results of a time-course study of hormonal effects on water and osmotic potentials indicated that BA stimulated cotyledon expansion and hypocotyl elongation primarily by increasing cell wall extensibility, whereas GA-promotion of cotyledon expansion and hypocotyl growth involved osmoregulation in addition to a lowering of the yielding threshold of the cell wall. Measurements of soluble sugars by a colorimetric procedure and cations by atomic absorption spectrometry confirmed that GA promoted the accumulation of osmotically active solutes in the cotyledons and hypocotyls.
","abstract_html":"<p>Apical applications of 0.2 micrograms N('6)-benzyladenine (BA), a synthetic cytokinin, or 5 micrograms gibberellic acid (GA) significantly enhanced hypocotyl elongation in intact dwarf watermelon seedlings. Accompanying the increase in hypocotyl length was increased expansion of the cotyledons and inhibition of root growth. A study on dry matter partitioning indicated that both hormones caused a preferential mobilization of metabolites from the cotyledons to the hypocotyl at an expense to roots. However, in comparison to untreated or GA-treated seedlings, BA decreased total translocation of metabolites out of the cotyledons. Hormonal effects on water potential of cotyledons and hypocotyls were determined by allowing organs to equilibrate for 2 h in serial concentrations of polyethylene glycol 4000. Osmotic potentials were determined with a dewpoint microvoltmeter. Results of a time-course study of hormonal effects on water and osmotic potentials indicated that BA stimulated cotyledon expansion and hypocotyl elongation primarily by increasing cell wall extensibility, whereas GA-promotion of cotyledon expansion and hypocotyl growth involved osmoregulation in addition to a lowering of the yielding threshold of the cell wall. Measurements of soluble sugars by a colorimetric procedure and cations by atomic absorption spectrometry confirmed that GA promoted the accumulation of osmotically active solutes in the cotyledons and hypocotyls.</p>","abstract_has_math":false,"creators":["ZACK, CHERYL DIANE"],"institution":null,"degree_name":"Doctor of Philosophy","degree_level":"Dissertation","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1981,"date_issued":"1981-01-01T08:00:00Z","date_published":"1981-01-01T08:00:00Z","updated_at":"2026-07-24T05:23:15Z","subjects":["Biology","Plant Physiology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholars.unh.edu/dissertation/1315","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["ZACK, CHERYL DIANE"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Doctor of Philosophy"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology","Plant Physiology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholars.unh.edu/dissertation/1315"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Apical applications of 0.2 micrograms N('6)-benzyladenine (BA), a synthetic cytokinin, or 5 micrograms gibberellic acid (GA) significantly enhanced hypocotyl elongation in intact dwarf watermelon seedlings. Accompanying the increase in hypocotyl length was increased expansion of the cotyledons and inhibition of root growth. A study on dry matter partitioning indicated that both hormones caused a preferential mobilization of metabolites from the cotyledons to the hypocotyl at an expense to roots. However, in comparison to untreated or GA-treated seedlings, BA decreased total translocation of metabolites out of the cotyledons. Hormonal effects on water potential of cotyledons and hypocotyls were determined by allowing organs to equilibrate for 2 h in serial concentrations of polyethylene glycol 4000. Osmotic potentials were determined with a dewpoint microvoltmeter. Results of a time-course study of hormonal effects on water and osmotic potentials indicated that BA stimulated cotyledon expansion and hypocotyl elongation primarily by increasing cell wall extensibility, whereas GA-promotion of cotyledon expansion and hypocotyl growth involved osmoregulation in addition to a lowering of the yielding threshold of the cell wall. Measurements of soluble sugars by a colorimetric procedure and cations by atomic absorption spectrometry confirmed that GA promoted the accumulation of osmotically active solutes in the cotyledons and hypocotyls.
"]},{"key":"dc:title","label":"Title","values":["COMPARATIVE EFFECTS OF GIBBERELLIC ACID AND N(6)-BENZYLADENINE ON GROWTH AND DEVELOPMENT OF DWARF WATERMELON SEEDLINGS"]}]}],"canonical_facts":{"dc:creator":["ZACK, CHERYL DIANE"],"dc:description.abstract":["Apical applications of 0.2 micrograms N('6)-benzyladenine (BA), a synthetic cytokinin, or 5 micrograms gibberellic acid (GA) significantly enhanced hypocotyl elongation in intact dwarf watermelon seedlings. Accompanying the increase in hypocotyl length was increased expansion of the cotyledons and inhibition of root growth. A study on dry matter partitioning indicated that both hormones caused a preferential mobilization of metabolites from the cotyledons to the hypocotyl at an expense to roots. However, in comparison to untreated or GA-treated seedlings, BA decreased total translocation of metabolites out of the cotyledons. Hormonal effects on water potential of cotyledons and hypocotyls were determined by allowing organs to equilibrate for 2 h in serial concentrations of polyethylene glycol 4000. Osmotic potentials were determined with a dewpoint microvoltmeter. Results of a time-course study of hormonal effects on water and osmotic potentials indicated that BA stimulated cotyledon expansion and hypocotyl elongation primarily by increasing cell wall extensibility, whereas GA-promotion of cotyledon expansion and hypocotyl growth involved osmoregulation in addition to a lowering of the yielding threshold of the cell wall. Measurements of soluble sugars by a colorimetric procedure and cations by atomic absorption spectrometry confirmed that GA promoted the accumulation of osmotically active solutes in the cotyledons and hypocotyls.
"],"dc:identifier":["https://scholars.unh.edu/dissertation/1315"],"dc:subject":["Biology","Plant Physiology"],"dc:title":["COMPARATIVE EFFECTS OF GIBBERELLIC ACID AND N(6)-BENZYLADENINE ON GROWTH AND DEVELOPMENT OF DWARF WATERMELON SEEDLINGS"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Doctor of Philosophy"]},"updated_at":"2026-07-24T05:23:15Z"}