Progress in Plant Growth Regulation

The current growing interest of molecular biologists in plant hormone research is undoubtedly the most promising development of recent times. Many papers were presented during the 14th International Conference on Plant Growth Substances illustrating the impact of this new approach on our understanding of hormone-controlled processes. The specific character is the integrated study of plant growth regulation at all levels ranging from single molecules to the entire plant and its functioning in the environment.
Hormones play an essential role in the regulation, but not an exclusive one. Other compounds and factors, such as Ca²⁺, for instance are often of equal relevance, because they may take part in the signal transduction pathway. Moreover, regulation of the regulator by non-hormonal factors is an essential part of any control mechanism.
The present volume reflects the change in interest from plant growth substances to plant growth regulation.

Genetics, chemistry, and biochemical physiology in the study of hormonal homeostasis.- Differential efficacy of gibberellins in flowering and vegetative shoot growth, including heterosis and inherently rapid growth.- Genetic approaches to hormone physiology Chairman: H. Kende.- The use of dominant mutations in the study of hormonal responses in plants.- Gibberellin mutants in Arabidopsis thaliana.- Probing hormone action in developing seeds by ABA-deficient and -insensitive mutants.- Photomorphogenetic mutants of higher plants.- Hormone perception and transduction Chairman: A. Trewavas.- Cytokinin signal transduction through Ca2+ in mosses.- Auxin binding proteins are located in the ER and in the plasma membrane: identification by photoaffmity-labelling and characterization.- Touch-induced regulation of expression of the calmodulin-related TCH genes and thigmomorphogenesis in Arabidopsis.- The role of Ca2+ in the action of GA in the barley aleurone.- The role of Ca2+ and ABA in the regulation of stomatal aperture.- Hormones and gene expression Chairman: D.T.-H. Ho.- Hormonal control of gene expression.- Transcriptional regulation of auxin-responsive genes.- The Gibberellin response element: a DNA sequence in cereal ?-amylase gene promoters that mediates GA and ABA effects.- Control of hormone synthesis and metabolism Chairman: J.A.D. Zeevaart.- Environmental control of ethylene biosynthesis.- Abscisic acid biosynthesis in higher plants.- Changes in abscisic acid levels of heterotrophic cell suspension cultures caused by the plant growth retardant BAS W and possible physiological consequences.- Ontogenetic and environmental effects on GA1 levels and the implications for the control of internode length.- Indole-3-acetic acid is converted to indole-3-butyric acid by seedlings of Zea mays L.- Control of sensitivity to hormones Chairman: P.J. Davies.- Differential sensitivities of protoplast responses to auxin.- Somatic embryogenesis as a developmental system to study modulation of auxin-binding capacity.- Changing membrane sensitivity to auxin during plant development.- The genetics and physiology of gibberellin sensitivity mutants in peas.- Quantitative assessment of hormone sensitivity changes with reference to stomatal responses to abscisic acid.- Target or non-target: hormonal signal perception and response in the determination of cell performance.- Ethylene-induced increase of sensitivity to auxin in Ranunculus petioles and its implications regarding ethylene action on adaptation.- Sensitivity in a wider context: ethylene and petiole growth Nymphoides peltata.- Other endogenous plant growth regulating substances Chairman: G. Sembdner.- Polyamines a new class of growth substances.- Jasmonates: metabolism, biological activities, and modes of action in senescence and stress responses.- Tuber forming substances of Jerusalem artichoke (Helianthus tuberosus L.).- Zearalenone, a key substance controlling plant development.- Transport and metabolism of brassinosteroids in rice.- Evidence for different types of acetylcholine receptors in plants.- Growth inhibitors A-2? and A-2?, and red light-induced growth inhibition in dwarf pea.- Brassinolide-induced elongation.- Triacontanol and its second messenger 9-?-L(+) adenosine.- Developmental biology at the cellular level Chairman: R.S. Quatrano.- Intercellular communication during plant epidermal cell redifferentiation.- Secreted proteins as modulators of plant embryogenesis.- Localization of cytosolic Ca2+ during carrot somatic embryogenesis using confocal scanning laser microscopy.- Phytohormones and osmotic stress in the regulation of embryo-specific gene expression in Brassica napus microspore embryos.- Perturbations in leaf development caused by the dominant Knotted-mutation in maize.- Bolting and floral induction in annual and cold-requiring biennial Brassica spp.: effects of photoperiod and exogenous gibberellin.- Possible model for the determination of vascular tissue in roots of Pisum sativum.- Heterophylly in amphibious Ranunculi: the effects of abscisic acid and methyl jasmonate.- Organ interactions Chairman: F. Bangerth.- Hormonal and metabolic control of tuber formation.- Interaction between vegetative and reproductive organs during early fruit development in pea.- Growth regulators and fruit development in Satsuma mandarin.- Hormonal control of apical dominance. Studies in tobacco transformed with bacterial luciferase and Agrobacterium rol genes.- The possible role of cytokinins, ethylene and indolacetic acid in apical dominance.- The role of indole-3-acetic acid in mediating changes in stem elongation of etiolated Pisum seedlings following exposure to light.- The influence of auxin transport inhibitor placement on stress-induced flower abscission in Capsicum.- Regulation of apoplastic sugar supply in crown gall tumours.- A model for bipolar plant-type growth: role of auxin-cytokin countercurrent.- Stress Chairman: K. Raschke.- Stress-induced redistribution kinetics of ABA in leaves: model considerations.- Molecular, cellular, and plant mechanisms of ABA control of stomatal aperture size.- Is stomatal conductance of plants in drying soil controlled by abscisic acid in the xylem stream?.- Developmental regulation of an ABA- and stress-induced protein in barley.- Plant-pathogen interactions Chairman: T. Boller.- Hormones in systemic acquired resistance: The role of salicylic acid.- Corynebacterium fascians: cytokinin production is positively correlated with virulence.- Phytoalexin elicitor-active ?-1, 4-D-oligogalacturonides reduce auxin perception by plant cells and tissues.- Nodule formation and hormone balance.- Ethylene antagonists increase nodulation on sym 5 pea mutants.- Pathways of gibberellin synthesis Chairman: N. Murofushi.- Regulation of gibberellin biosynthesis in maize seedlings.- The biosynthesis of ent-kaurene in germinating seeds and the function of 2oxoglutarate in gibberellin biosynthesis.- Useful probes to study the biosynthesis of gibberellins.- Identification of native gibberellin-O-glucosides in Zea mays L. and Hordeum vulgare L..- The mode of action of acylcyclohexanediones – a new type of growth retardant.- The effect of the growth retardant LAB 198 999 and its interaction with gibberellins A1, A3, and A20 in fruit growth of tall and dwarf peas.- Phytochrome modulation of gibberellin metabolism in cowpea epicotyls.- Characterization of the effect of seeds on gibberellin metabolism in pea pericarp.- Cytokinin metabolism Chairman: M. Laloue.- Zeatin metabolism in Phaseolus: enzymes and genes.- Control of cytokinin levels by inhibitors of metabolism, symbiosis and genetic manipulation.- Zeatin allylic phosphate: occurrence, formation and possible role.- Cytokinin-induced shoot elongation in Syringa vulgaris L. in vitro.- Effect of growth substances and mineral nutrients on cytokinin levels and senescence of tobacco (Nicotiana rustica) leaves.- Electrophysiology and calcium Chairman: H. Felle.- Effects of abscisic acid and abscisic acid analogues on intracellular calcium level and gene expression in barley aleurone protoplasts.- ABA and GA 3, regulate CA2+-buffering in the cytosol and endoplasmic reticulum of barley aleurone cells.- Cytoplasmic calcium, calcium currents and fluxes during fertilization and early development of Fucus serratus.- The role of cytosolic calcium, pH and auxin-induced electrical responses for elongation growth in maize.- Whole-cell patch-clamp experiments on tobacco protoplasts.- The plasma membrane Ca2+ pump: potential role in Ca2+ homeostasis.- Biochemical characterization of a dual reconstituted system responsive to fusicoccin.- Calmodulin gene expression and Ca2+/calmodulin-dependent protein kinase II in plants.- Phytohormones and calmodulin inhibitor in elongation growth of soybean hypocotyl segments.- Effect of day length on stomatal opening and their response to phytochrome.- Biotechnological approaches to plant breeding Chairman: H.A. van Onckelen.- Transgenic tobacco plants with heat-inducible IAA synthesis genes.- Transgenic plants and transgenic plant mosaics for the expression of pathogen derived genes able to affect phytohormone activity.- 1-Aminocyclopropane-l-carboxylate synthase genes: present and future.- Morphological characteristics and phytohormone content of ipt-transgenic tobacco.- Effect of auxin on thiophene synthesis and root morphology in Tagetes patula hairy root cultures.- Field testing transgenic cucumber plants that express the CMV coat protein gene.- A functional analysis of the plant hormone-regulated dual mannopine synthase (mas) promoter region.- Expression of luciferase in transgenic tobacco mediated by a promoterelement from desiccation tolerant Craterostigma plantagineum.- Genetic variation in ABA production in maize determines the extent of drought-induced gene transcription.- Agricultural uses of plant growth regulators Chairman: W. Rademacher.- Mode of action and use of plant growth retardants in reducing the effects of environmental stress on horticultural crops.- Plant growth retardants: their mode of action and benefit for physiological research.- Use of plant growth regulators in arable crops: survey and outlook.- The use of growth retardants for the regulation and acclimatization of in vitro plants.- Studies on the action of the new growth retardant CGA 163’935(Cimectacarb).- Ethylene, ACC, MACC and ethephon metabolism in ethephon treated field grown barley (Hordeum vulgare L. cv. ‘Bonanza’).- Enhancement of seedling vigor in rice (Oryza sativa L.) by seed treatment with gibberellic acid.- Physiology and application of phenylurea cytokinins.- The use of anti-gibberellins in the production of tulips as pot plants.- New developments in hormone analysis Chairman: G.W.M. Barendse.- Stable isotype techniques for the analysis of indole auxin metabolism in normal and mutant plants.- Preparation and application of antibodies for non-derivatized gibberellins.- Rapid ethylene release and stimulated ethylene production after de-submergence of plants: an analysis with a continuous flow system in line with a laser-driven intracavity photoacoustic ethylene detector.- An ELISA to determine exogenously applied gibberellic acid in leaves of cut Alstroemeria stems.- Liquid chromatography/atmospheric pressure chemical ionization mass spectrometry of gibberellin conjugates.- Immunocytochemical localization of auxins and cytokinins in the moss Funaria hygrometrica.- Tropisms Chairman: R.D. Firn.- On the role of the NPA receptor in the root gravitropic response mechanism.- The gravitropic tomato mutant lazy-2 is altered in signal transduction.- Genetic analysis of tropisms of Arabidopsis thaliana.- Molecular modelling of auxin transport inhibitors.- Index of Authors.- Index of Keywords.