The small phenolic compound salicylic acid (SA) is critical for plant defense against a broad spectrum of pathogens. SA is also involved in multi-layered defense responses, from pathogen-associated molecular pattern triggered basal defense, resistance gene-mediated defense, to systemic acquired resistance. Recent decades have witnessed tremendous progress towards our understanding of SA-mediated signaling networks. Many genes have been identified to have direct or indirect effect on SA biosynthesis or to regulate SA accumulation. Several SA receptors have been identified and characterization of these receptors has shed light on the mechanisms of SA-mediated defense signaling, which encompass chromosomal remodeling, DNA repair, epigenetics, to transcriptional reprogramming. Molecules from plant-associated microbes have been identified, which manipulate SA levels signaling. SA does not act alone. It engages in crosstalk with other signaling pathways, such as those mediated by other phytohormones, in an agonistic or antagonistic manner, depending on hormones and pathosystems. Besides affecting plant innate immunity, SA has also been implicated in other cellular processes, such as flowering time determination, lipid metabolism, circadian clock control, and abiotic stress responses, possibly contributing to the regulation of plant development. The multifaceted function of SA makes it critically important to further identify genes involved in SA signaling networks, understand their modes of action, and delineate interactions among the components of SA signaling networks. In addition, genetic manipulation of genes involved in SA signaling networks has also provided a promising approach to enhance disease resistance in economically important plants. This ebook collects articles in the research topic “Salicylic Acid Signaling Networks.” For this collection we solicited reviews, perspectives, and original research articles that highlight recent exciting progress on the understanding of molecular mechanisms underlying SA-mediated defense, SA-crosstalk with other pathways and how microbes impact these events.

Salicylic acid (SA) and methyl jasmonate (MJ) signaling is associated with phospholipids and the enzymes that metabolize them. However, despite the many studies conducted, the role of SA or MJ signalling via phospholipids in plant responses is not yet fully understood. The signaling pathways of SA and MJ have been evaluated in plant cell suspensions, and it was observed that these compounds regulate enzymatic activities to generate a rapid cellular response. This book discusses the immune responses induced by salicylic acid and jasmonic acids against plant parasites; the induction by SA of in vitro thermotolerance during thermotherapy; aalicylic acid, methyl jasmonate and phospholipid signaling in suspension cells; the self-association of salicylic acid derivatives in aqueous solutions studied by methods of absorption and fluorescence; and the role of exogenous salicylic acid applications for salt tolerance in tomato plants.

Bei vielen physiologischen und Entwicklungsprozessen sowie bei Stressreaktionen spielen Hormonsignale, die Pflanzen aussenden, eine große Rolle. Mit Aufkommen der neuen post-genomischen Molekulartechnologien sind auch unsere Möglichkeiten, die Wirkung von Hormonsignalen auf die Genexpression und adaptive Prozesse zu verstehen, heute einzigartig. Wenn wir die molekularen Grundlagen dieser Prozesse entschlüsseln, ergeben sich für die Entwicklung neuer Pflanzenbiotechnologien und verbesserter Varianten von Kulturpflanzen große Chancen. Die Themen dieses Buches legen den Schwerpunkt auf die Genomik und funktionale Aspekte der Genomik. Damit lassen sich globale Veränderungen und Veränderungen auf Ebene des gesamten Genoms unter spezifischen Stressbedingungen verstehen. Mit funktionalen Werkzeugen der Genomik kann der Mechanismus von Phytohormonsignalen in Verbindung mit den zugehörigen Zielgenen systematischer definiert werden. Die integrierte Analyse von Phytohormonsignalen bei einzelnen oder mehreren Stressbedingungen ist unter Umständen für die Entwicklung stresstoleranter Kulturpflanzen eine außergewöhnliche Möglichkeit. Mechanism of Plant Hormone Signaling Under Stress beschreibt die jüngsten Fortschritte und zeigt, wie heutige Erkenntnisse in der wissenschaftlichen Erforschung von Pflanzen und Kulturpflanzen Anwendung finden. Dieses Buch ist für Pflanzenbiologen, Biologen, die sich mit Stressfaktoren beschäftigen, Forscher im Bereich Pflanzenbiotechnologie, Studenten und Dozenten überaus nützlich.

Demand for agricultural crops and nutritional requirement continues to escalate in response to increasing population. Also, climate change exerts adverse effects on agriculture crop productivity. Plant researchers have, therefore, focused to identify the scientific approaches that minimize the negative impacts of climate change on agricultural crops. Thus, it is the need of the hour to expedite the process for improving stress tolerance mechanisms in agricultural crops against various environmental factors, in order to fulfil the world’s food demand. Among the various applied approaches, the application of phytohormones has gained significant attention in inducing stress tolerance mechanisms. Jasmonates are phytohormones with ubiquitous distribution among plants and generally considered to modulate many physiological events in higher plants such as defence responses, flowering and senescence. Also, jasmonates mediate plant responses to many biotic and abiotic stresses by triggering a transcriptional reprogramming that allows cells to cope with pathogens and stresses. Likewise, salicylates are important signal molecules for modulating plant responses to environmental stresses. Salicylic acid influences a range of diverse processes in plants, including seed germination, stomatal closure, ion uptake and transport, membrane permeability and photosynthetic and growth rate. Understanding the significant roles of these phytohormones in plant biology and from agriculture point of view, the current subject has recently attracted the attention of scientists from across the globe. Therefore, we bring forth a comprehensive book “Jasmonates and Salicylates Signalling in Plants” highlighting the various prospects involved in the current scenario. The book comprises chapters from diverse areas dealing with biotechnology, molecular biology, proteomics, genomics, metabolomics, etc. We are hopeful that this comprehensive book furnishes the requisite of all those who are working or have interest in this topic.

Although the role of salicylic acid (SA) in plant physiological processes has been widely studied for a long time, many open questions remain several fields. The importance of SA synthesis is illustrated by the four review papers published in this Special Issue that represent a wide range of approaches, indicating that a growing body of evidence needs to be summarized in a thought-provoking manner. The investigations presented in the six original studies extend upon the understanding of the involvement of SA in anthracnose infection and light-dependent cold acclimation, highlighting the use of SA mutant Arabidopsis plants. The studies also focused on the application of novel SA analogs or SA in combination with Rhizobacteria inoculation. We hope that the four reviews and six studies provide a deeper understanding of the role of SA and its complex tasks, as well as a new direction for research to address gaps and open questions, including both at the metabolite and gene expression levels, in the use of agriculturally important crop or mutant model plants, and in both basic research and practical applications.

Lipids in Photosynthesis: Essential and Regulatory Functions, provides an essential summary of an exciting decade of research on relationships between lipids and photosynthesis. The book brings together extensively cross-referenced and peer-reviewed chapters by prominent researchers. The topics covered include the structure, molecular organization and biosynthesis of fatty acids, glycerolipids and nonglycerolipids in plants, algae, lichens, mosses, and cyanobacteria, as well as in chloroplasts and mitochondria. Several chapters deal with the manipulation of the extent of unsaturation of fatty acids and the effects of such manipulation on photosynthesis and responses to various forms of stress. The final chapters focus on lipid trafficking, signaling and advanced analytical techniques. Ten years ago, Siegenthaler and Murata edited "Lipids in Photosynthesis: Structure, Function and Genetics," which became a classic in the field. "Lipids in Photosynthesis: Essential and Regulatory Functions," belongs, with its predecessor, in every plant and microbiological researcher's bookcase.

Plant Signaling Molecule: Role and Regulation under Stressful Environments explores tolerance mechanisms mediated by signaling molecules in plants for achieving sustainability under changing environmental conditions. Including a wide range of potential molecules, from primary to secondary metabolites, the book presents the status and future prospects of the role and regulation of signaling molecules at physiological, biochemical, molecular and structural level under abiotic stress tolerance. This book is designed to enhance the mechanistic understanding of signaling molecules and will be an important resource for plant biologists in developing stress tolerant crops to achieve sustainability under changing environmental conditions. - Focuses on plant biology under stress conditions - Provides a compendium of knowledge related to plant adaptation, physiology, biochemistry and molecular responses - Identifies treatments that enhance plant tolerance to abiotic stresses - Illustrates specific physiological pathways that are considered key points for plant adaptation or tolerance to abiotic stresses

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

Plant resistance to pathogens is one of the most important strategies of disease control. Knowledge of resistance mechanisms, and of how to exploit them, has made a significant contribution to agricultural productivity. However, the continuous evolution of new variants of pathogen, ana additional control problems posed by new crops and agricultural methods, creates a need for a corresponding increase in our understanding of resistance and ability to utilize it. The study of resistance mechanisms also has attractions from a purely academic point of view. First there is the breadth of the problem, which can be approached at the genetical, molecular, cellular, whole plant or population lev~ls. Often there is the possibility of productive exchange of ideas between different disciplines. Then there is the fact that despite recent advances, many of the mechanisms involved have still to be fully elucidated. Finally, and compared with workers in other areas of biology, the student of resistance is twice blessed in having as his subject the interaction of two or more organisms, with the intriguing problems of recognition, specificity and co-evolution which this raises.