Effect of asymmetric auxin application on Helianthus hypocotyl curvature

• Published in: Plant physiology (Bethesda) Vol. 91; no. 2; pp. 466 - 468
• Main Authors: Migliaccio, F. (Yale University, New Haven, CT), Rayle, D.L
• Format: Journal Article
• Language: English
• Published: Headquarters American Society of Plant Physiologists 01.10.1989
• Subjects: ACIDE INDOLACETIQUE; ACIDO INDOLACETICO; Auxins; Biological and medical sciences; Coleoptiles; Communications; Curvature; Dose-Response Relationship, Drug; Fundamental and applied biological sciences. Psychology; Gravitation; Gravitropism; Gravitropism - drug effects; Gravitropism - physiology; Growth substances; Helianthus - drug effects; Helianthus - growth & development; Helianthus - physiology; HELIANTHUS ANNUUS; HIPOCOTILOS; Hypocotyl - drug effects; Hypocotyl - growth & development; Hypocotyl - physiology; HYPOCOTYLE; Hypocotyls; INDICE DE CRECIMIENTO; Indoleacetic Acids - pharmacology; Indoleacetic Acids - physiology; Life Sciences (General); Physical agents; Plant cells; Plant physiology and development; Plant Shoots - drug effects; Plant Shoots - growth & development; Plant Shoots - physiology; Plants; PLANTULAS; PLANTULE; Rotation; Seedlings; Space life sciences; Sunflowers; TAUX DE CROISSANCE; TROPISME; TROPISMO; Vegetative apparatus, growth and morphogenesis. Senescence; Nasa Discipline Plant Biology; Nasa Program Space Biology; Nasa Discipline Number 29-20; Non-Nasa Center; Gradient; Auxin; Compositae; Oil plant(vegetal); Helianthus annuus; Hypocotyl; Asymmetry; Dicotyledones; Angiospermae; Plant growth substance; Spermatophyta; Curvature; Geotropism; NASA Program Space Biology; NASA Discipline Number 29-20; NASA Discipline Plant Biology; Non-NASA Center
• ISSN: 0032-0889; 1532-2548
• DOI: 10.1104/pp.91.2.466

Indole-3-acetic acid was applied asymmetrically to the hypocotyls of sunflower (Helianthus annuus L.) seedlings. After 5 hours on a clinostat, auxin gradients as small as 1 to 1.3 produced substantial (more than 60 degrees) hypocotyl curvature. This result suggests the asymmetric growth underlying hypocotyl gravitropism can be explained by lateral auxin redistribution.