title: Mutants of Nicotiana plumbaginifolia with increased sensitivity to auxin.
abstract: Two non-allelic, monogenic recessive mutations, aus1 and aus2, have been isolated which result in auxin hypersensitivity in mutant Nicotiana plumbaginifolia plants. At relatively low concentrations of indole-3-acetic acid or 1-naphthaleneacetic acid, the elongation growth of mutant seedling hypocotyls is more inhibited than in the case of the wild type; at high auxin concentrations, mutant seedlings are killed. The leaves of mature mutant plants degenerate after a spray treatment with auxin that has only a mild, transient effect on the wild type. Seedling hypocotyls of aus1 are more sensitive to L-tryptophan than those of the wild type but do not differ in their response to the D-isomer. The mutant is also more sensitive to ethylene and the ethylene precursor 1-aminocyclopropane-1-carboxylic acid, but not to either 6-benzyladenine or abscisic acid. Mutant seedlings display several distinct morphological characters: mild leaf epinasty, short primary root, increased root branching and no root hairs.
authors.affiliation: Friedrich Miescher-Institut, Basel, Switzerland.
authors.forename: L
authors.initials: L
authors.lastname: de Souza
authors.forename: P J
authors.initials: PJ
authors.lastname: King
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D000225:Adenine / Q000031:analogs & derivatives / Q000494:pharmacology; D000596:Amino Acids / Q000494:pharmacology; D000598:Amino Acids, Cyclic; D001593:Benzyl Compounds; D004305:Dose-Response Relationship, Drug; D005030:Ethylenes / Q000494:pharmacology; D005808:Genes, Recessive / Q000235:genetics; D007210:Indoleacetic Acids / Q000494:pharmacology*; D007701:Kinetin; D009154:Mutation / Q000235:genetics; D010641:Phenotype; D010947:Plants, Toxic; D011687:Purines; D013237:Stereoisomerism; D014026:Nicotiana / Q000187:drug effects* / Q000235:genetics; D014364:Tryptophan / Q000494:pharmacology
chemical_list: D000596:Amino Acids; D000598:Amino Acids, Cyclic; D001593:Benzyl Compounds; D005030:Ethylenes; D007210:Indoleacetic Acids; D011687:Purines; C023863:1-aminocyclopropane-1-carboxylic acid; D000040:Abscisic Acid; D014364:Tryptophan; C036216:ethylene; D000225:Adenine; C480551:benzylaminopurine; D007701:Kinetin