{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/22140"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/22140","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Regulation of growth and storage product metabolism in cultured kernels of maize","abstract":"Maize (Zea mays L.) kernel growth and grain yield are functions of endosperm starch accumulation. In vitro seed culture was used to study the influence of assimilate supply on the growth and composition of maize endosperm and to determine how various metabolic events in developing endosperm are related to starch accumulation. Immature kernels were grown to maturity on liquid medium containing different concentrations of C (as sucrose) and N (as an amino acid mixture). Endosperm starch and protein syntheses responded to N supply in much the same way as do kernels grown on the intact plant. Protein accumulation was generally independent of sucrose concentration in the medium, while starch synthesis was reduced by low C supply. Extremely low or high concentrations of N also interfered with starch metabolism, possibly through a deficiency in metabolic enzymes or an osmotic imbalance. The relationship between starch and protein accumulation was dependent, at least in appearance, under low N and independent otherwise.","abstract_html":"Maize (Zea mays L.) kernel growth and grain yield are functions of endosperm starch accumulation. In vitro seed culture was used to study the influence of assimilate supply on the growth and composition of maize endosperm and to determine how various metabolic events in developing endosperm are related to starch accumulation. Immature kernels were grown to maturity on liquid medium containing different concentrations of C (as sucrose) and N (as an amino acid mixture). Endosperm starch and protein syntheses responded to N supply in much the same way as do kernels grown on the intact plant. Protein accumulation was generally independent of sucrose concentration in the medium, while starch synthesis was reduced by low C supply. Extremely low or high concentrations of N also interfered with starch metabolism, possibly through a deficiency in metabolic enzymes or an osmotic imbalance. The relationship between starch and protein accumulation was dependent, at least in appearance, under low N and independent otherwise.","abstract_has_math":false,"creators":["Singletary, George William"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Agronomy","degree_department":null,"school":null,"contributors":["Below, Frederick E."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:30:16Z","date_published":"2011-05-07T13:30:16Z","updated_at":"2026-07-22T22:25:19Z","subjects":["Chemistry, Biochemistry","Biology, Plant Physiology"],"languages":["eng"],"rights":["Copyright 1989 Singletary, George William"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8924944","(UMI)AAI8924944"],"render_values":[{"text":"AAI8924944","href":null,"code":true},{"text":"(UMI)AAI8924944","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/22140","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Below, Frederick E."]},{"key":"dc:creator","label":"Author","values":["Singletary, George William"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T13:30:16Z","10000-01-01","1989"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Agronomy"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Chemistry, Biochemistry","Biology, Plant Physiology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1989 Singletary, George William"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI8924944","(UMI)AAI8924944","http://hdl.handle.net/2142/22140"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Maize (Zea mays L.) kernel growth and grain yield are functions of endosperm starch accumulation. In vitro seed culture was used to study the influence of assimilate supply on the growth and composition of maize endosperm and to determine how various metabolic events in developing endosperm are related to starch accumulation. Immature kernels were grown to maturity on liquid medium containing different concentrations of C (as sucrose) and N (as an amino acid mixture). Endosperm starch and protein syntheses responded to N supply in much the same way as do kernels grown on the intact plant. Protein accumulation was generally independent of sucrose concentration in the medium, while starch synthesis was reduced by low C supply. Extremely low or high concentrations of N also interfered with starch metabolism, possibly through a deficiency in metabolic enzymes or an osmotic imbalance. The relationship between starch and protein accumulation was dependent, at least in appearance, under low N and independent otherwise.","To study metabolism in relation to starch accumulation, kernels were grown on medium with: (a) zero N ($-$N), (b) N optimum for growth (+N), or (c) $-$N from 3 to 20 days after pollination followed by +N until maturity ($-$/+N). Endosperm starch and protein accumulation were greatly reduced in $-$N kernels, but enhanced in $-$/+N, relative to $-$N, endosperm. A reciprocity occurred between endosperm concentrations of free sugars and amino-N. Endosperm growth of N stressed kernels ($-$N, $-$/+N) was not limited by C substrate but, instead, by an apparent inability to utilize reducing sugars and a low content of albumin/globulin proteins. Of nine C metabolism enzymes assayed, only sucrose synthase and PPi-linked phosphofructokinase increased in activity concurrent with the promotion of starch accumulation in $-$/+N kernels. Greater activity of PPi-linked phosphofructokinase in $-$/+N endosperm may have been related to the enhanced utilization of reducing sugars. Electrophoretic analysis indicated additional proteins (albumin/globulins) that changed in relative amount in association with changes in starch accumulation. These data suggest that sucrose synthase, PPi-linked phosphofructokinase, and/or specific albumin/globulin proteins may have important roles in the regulation of starch synthesis in maize endosperm.","Made available in DSpace on 2011-05-07T13:30:16Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8924944.pdf: 3051989 bytes, checksum: 507869ffc17d3e959fc0219582f54101 (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:55:36Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:25:55-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","U of I Only"]},{"key":"dc:title","label":"Title","values":["Regulation of growth and storage product metabolism in cultured kernels of maize"]}]}],"canonical_facts":{"dc:contributor":["Below, Frederick E."],"dc:creator":["Singletary, George William"],"dc:date":["2011-05-07T13:30:16Z","10000-01-01","1989"],"dc:description":["Maize (Zea mays L.) kernel growth and grain yield are functions of endosperm starch accumulation. In vitro seed culture was used to study the influence of assimilate supply on the growth and composition of maize endosperm and to determine how various metabolic events in developing endosperm are related to starch accumulation. Immature kernels were grown to maturity on liquid medium containing different concentrations of C (as sucrose) and N (as an amino acid mixture). Endosperm starch and protein syntheses responded to N supply in much the same way as do kernels grown on the intact plant. Protein accumulation was generally independent of sucrose concentration in the medium, while starch synthesis was reduced by low C supply. Extremely low or high concentrations of N also interfered with starch metabolism, possibly through a deficiency in metabolic enzymes or an osmotic imbalance. The relationship between starch and protein accumulation was dependent, at least in appearance, under low N and independent otherwise.","To study metabolism in relation to starch accumulation, kernels were grown on medium with: (a) zero N ($-$N), (b) N optimum for growth (+N), or (c) $-$N from 3 to 20 days after pollination followed by +N until maturity ($-$/+N). Endosperm starch and protein accumulation were greatly reduced in $-$N kernels, but enhanced in $-$/+N, relative to $-$N, endosperm. A reciprocity occurred between endosperm concentrations of free sugars and amino-N. Endosperm growth of N stressed kernels ($-$N, $-$/+N) was not limited by C substrate but, instead, by an apparent inability to utilize reducing sugars and a low content of albumin/globulin proteins. Of nine C metabolism enzymes assayed, only sucrose synthase and PPi-linked phosphofructokinase increased in activity concurrent with the promotion of starch accumulation in $-$/+N kernels. Greater activity of PPi-linked phosphofructokinase in $-$/+N endosperm may have been related to the enhanced utilization of reducing sugars. Electrophoretic analysis indicated additional proteins (albumin/globulins) that changed in relative amount in association with changes in starch accumulation. These data suggest that sucrose synthase, PPi-linked phosphofructokinase, and/or specific albumin/globulin proteins may have important roles in the regulation of starch synthesis in maize endosperm.","Made available in DSpace on 2011-05-07T13:30:16Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 8924944.pdf: 3051989 bytes, checksum: 507869ffc17d3e959fc0219582f54101 (MD5) Previous issue date: 1989","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:55:36Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:25:55-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","Restricted to the U of I community indefinitely during batch ingest of legacy ETDs","U of I Only"],"dc:identifier":["AAI8924944","(UMI)AAI8924944","http://hdl.handle.net/2142/22140"],"dc:language":["eng"],"dc:rights":["Copyright 1989 Singletary, George William"],"dc:subject":["Chemistry, Biochemistry","Biology, Plant Physiology"],"dc:title":["Regulation of growth and storage product metabolism in cultured kernels of maize"],"dc:type":["text"],"thesis:degree_discipline":["Agronomy"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:19Z"}