Gibberellins And Plant Growth

Extraction, purification and chemistry of gibberellins. Gibberellin bioassays. Biosynthesis, metabolism, transport and distribution of gibberellins. Role of gibberellins in dormancy and seed germination. Role of gibberellins in root and shoot growth. Role of gibberellins in juvenility, flowering and sex expression. Role of gibberellins in the development of fruits and seeds. Regulation of leaf and fruit and seeds. Regulation of leaf and fruit senescence by gibberellic acid. Role of gibberellins in abscission of leaves and fruits. The morphological, anatomical and cytological effects of gibberellins.

First discovered as fungal metabolites, the gibberellins were recognised as plant hormones over 50 years ago. They regulate reproductive development in all vascular plants, while their role in flowering plants has broadened to include also the regulation of growth and other developmental processes. This timely book covers the substantial and impressive recent advances in our understanding of the gibberellins and their roles in plant development, including the biosynthesis, inactivation, transport, perception and signal transduction of these important hormones. An introductory chapter traces the history of gibberellin research, describing the many discoveries that form the basis for the recent progress. The exciting emerging evidence for the interaction of gibberellin signalling with that of the other hormones is critically evaluated. The occurrence of gibberellins in fungal, bacterial and lower plant species is also discussed, with emphasis on evolution. Manipulation of gibberellin metabolism and signal transduction through chemical or genetic intervention has been an important aspect of crop husbandry for many years. The reader is presented with important information on the advances in applying gibberellin research in agriculture and horticulture. Annual Plant Reviews, Volume 49: The Gibberellins is an important resource for plant geneticists and biochemists, as well as agricultural and horticultural research workers, advanced students of plant science and university lecturers in related disciplines. It is an essential addition to the shelves of university and research institute libraries and agricultural and horticultural institutions teaching and researching plant science.

This book provides current information on synthesis of plant hormones, how their concentrations are regulated, and how they modulate various plant processes. It details how plants sense and tolerate such factors as drought, salinity, and cold temperature, factors that limit plant productivity on earth. It also explains how plants sense two other environmental signals, light and gravity, and modify their developmental patterns in response to those signals. This book takes the reader from basic concepts to the most up-to-date thinking on these topics. * Provides clear synthesis and review of hormonal and environmental regulation of plant growth and development * Contains more than 600 illustrations supplementary information on techniques and/or related topics of interest * Single-authored text provides uniformity of presentation and integration of the subject matter * References listed alphabetically in each section

The processes and mechanisms that control the growth of woody plants are of crucial importance for both economic and biological reasons. The comprehensive coverage of Growth Control in Woody Plants includes discussion of the growth controlling factors in both reproductive structures (flowers, fruit, seeds, pollen, etc.) and vegetative organs (stems, branches, leaves, and roots). Other major topics covered include seed germination, seedling growth, physiological and environmental regulation of growth, cultural practices, and biotechnology. This comprehensive treatment of the many factors that control the growth of woody plants can serve both as a valuable text and as a frequently used reference. * Includes comprehensive representation of a broad subject * Provides thorough bibliographic coverage * Well illustrated * Serves as a vital companion to Physiology of Woody Plants, Second Edition

Plant hormones have pivotal roles in the regulation of plant growth, development, and reproduction. Their signaling pathways are interconnected in a complex network, which provides plants with an enormous regulatory potential to rapidly adapt to their environment and to utilize their limited resources for growth and survival in a cost-efficient manner. Auxin is a hormone molecule whose activity levels are most important for its regulatory roles during plant cell, organ, and tissue development. Therefore, the precise regulation of auxin levels is an essential mechanism to fine-tune the activity of this powerful hormone during plant growth and development. Likewise, cytokinins exhibit a wide range of physiological functions, including regulation of shoot and root apical meristems, stimulation of branching, vascular development, chloroplast differentiation, stabilization of the structure and function of the photosynthetic machinery, delay of senescence, stomata opening, and elevation of the sink strength and nutritional signaling. Moreover, gibberellins also regulate many aspects of plant growth and development including seed germination, stem elongation, leaf expansion, and flower and fruit development. The broad implication of gibberellins in plant development is strictly associated with tight regulation of their metabolism by multiple environmental and endogenous factors, ranging from light and temperature to other hormones including feedback control. Understanding the significant roles of these phytohormones in plant biology, the current subject has attracted the attention of scientists from across the globe. This comprehensive volume “Auxins, Cytokinins and Gibberellins Signaling in Plants” highlights the various prospects involved in the current scenario. The book comprises the chapters from diverse areas dealing with biotechnology, molecular biology, proteomics, genomics, metabolomics, etc.

Plant Hormones: Biosynthesis and Mechanisms of Action is based on research funded by the Chinese government’s National Natural Science Foundation of China (NSFC). This book brings a fresh understanding of hormone biology, particularly molecular mechanisms driving plant hormone actions. With growing understanding of hormone biology comes new outlooks on how mankind values and utilizes the built-in potential of plants for improvement of crops in an environmentally friendly and sustainable manner. This book is a comprehensive description of all major plant hormones: how they are synthesized and catabolized; how they are perceived by plant cells; how they trigger signal transduction; how they regulate gene expression; how they regulate plant growth, development and defense responses; and how we measure plant hormones. This is an exciting time for researchers interested in plant hormones. Plants rely on a diverse set of small molecule hormones to regulate every aspect of their biological processes including development, growth, and adaptation. Since the discovery of the first plant hormone auxin, hormones have always been the frontiers of plant biology. Although the physiological functions of most plant hormones have been studied for decades, the last 15 to 20 years have seen a dramatic progress in our understanding of the molecular mechanisms of hormone actions. The publication of the whole genome sequences of the model systems of Arabidopsis and rice, together with the advent of multidisciplinary approaches has opened the door to successful experimentation on plant hormone actions. Offers a comprehensive description of all major plant hormones including the recently discovered strigolactones and several peptide hormones Contains a chapter describing how plant hormones regulate stem cells Offers a fresh understanding of hormone biology, particularly molecular mechanisms driving plant hormone actions Discusses the built-in potential of plants for improvement of crops in an environmentally friendly and sustainable manner

The cultivation of rice in Japan has suffered from damage caused by baka nae disease, in which rice seedlings show abnormal growth (elongation) as the result of infection by a plant pathogen. Investigation of the taxonomy of this pathogen led to the commencement of gibberellin (GA) research among Japanese plant pathologists, who later identified it as Gibberella jujikuroi, its other name being Fusarium moniliforme. In 1926, Kurosawa demon strated the occurrence of an active principle in the culture media of fungus that showed the same symptoms as those of the rice disease. In 1938, this finding was followed by the successful isolation of the active principles as crystals from the culture filtrate. This was achieved by the Japanese agri cultural chemists Yabuta and Sumiki, of The University of Tokyo, who named these active principles gibberellins A and B. Following World War II, this discovery attracted the interest of scientists around the world, and research on GA was pursued on a worldwide scale. One of the most outstanding discoveries in GA research after the isolation of GA as the metabolite of the plant pathogen must be the isolation and characterization of GAs from tissues of higher plants by the MacMillan group, West and Phinney, and the Tokyo University group in 1958 and 1959. Thus, GAs have been recognized as one of the most important classes of plant hormones.