title: Influence of the shoot tip and leaves on circumnutation in green pea seedlings.
abstract: Portions of the shoot system from young light-grown pea (Pisum sativum L.) seedlings were excised and circumnutation studied using time-lapse cinematography. Removal of the youngest leaf or shoot tip as well as ringing the stem with 20 mM triiodobenzoic acid severely restricted circumnutation. Treating the stump of the excised leaf with lanolin containing 10(-4) M indole-3-acetic acid or replacing the leaf with an artificial aluminum leaf both partially restored circumnutation. When the leaf was replaced with both auxin and an artificial leaf circumnutation continued at approximately the rate of the intact plant. This graphically shows the involvement of both auxin and gravitropism in circumnutation.
authors.affiliation: State University of New York, Department of Environmental and Forest Biology, Syracuse, NY 13210, USA.
authors.forename: H B
authors.initials: HB
authors.lastname: Tepper
authors.forename: R L
authors.initials: RL
authors.lastname: Yang
mesh_terms: D004643:Emollients / Q000494:pharmacology; D018522:Gravitropism / Q000187:drug effects / Q000502:physiology; D007210:Indoleacetic Acids / Q000378:metabolism / Q000494:pharmacology*; D007809:Lanolin / Q000494:pharmacology; D018532:Pisum sativum / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism / Q000502:physiology; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology*; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D014283:Triiodobenzoic Acids / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D004643:Emollients; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D014283:Triiodobenzoic Acids; C030737:indoleacetic acid; D007809:Lanolin