title: Promotion of growth and hydrogen ion efflux by auxin in roots of maize pretreated with ethylene biosynthesis inhibitors.
abstract: Low concentrations of auxin (e.g. 10(-10)m) do not promote the growth of intact seedling roots of maize (Zea mays L. Bear Hybrid WF 9 x 38). Higher concentrations are inhibitory. When the roots are pretreated with the ethylene biosynthesis inhibitors, cobalt and aminoethoxyvinylglycine, auxin (10(-10) to 10(-8)m) strongly promotes their growth. The promotion of growth by auxin in pretreated roots is preceded by enhanced hydrogen ion secretion from the roots. The data indicate that hormone-enhanced hydrogen ion secretion may play a role in the rapid promotion of root growth by auxin. The ability of auxin to promote the growth of intact roots is discussed in relation to the Cholodny/Went hypothesis of hormonal control of root geotropism.
authors: Department of Botany, Ohio State University, Columbus, Ohio 43210.
authors: T J
authors: TJ
authors: Mulkey
authors: K M
authors: KM
authors: Kuzmanoff
authors: M L
authors: ML
authors: Evans