Senescence and Aging in Plants reviews the state of knowledge in the processes involved in plant senescence and aging. The book begins by discussing the emergence of senescence as a concept; experimental analysis of senescence; and patterns of senescence. It then examines membrane deterioration during senescence; photosynthesis in relation to leaf senescence; senescence of detached plant organs; changing patterns of nucleic acid and protein synthesis during senescence; and degradative and associated assimilatory aspects of nitrogen removal. This is followed by chapters on aspects of ethylene that may impinge upon its role in promoting senescence of higher plants; the role of cytokinins in plant senescence; the promoters and retardants of senescence; and the role of calcium in plant senescence. The concept of whole plant senescence is discussed, which can be subdivided into patterns, correlative controls, cessation of vegetative growth, declining assimilatory processes, assimilate partitioning, and hormonal controls. The final chapters cover the deterioration of cellular membranes during the plant aging process and seed aging.

Senescence Signalling and Control in Plants discusses the studies showing the importance of hormone action on developmental senescence. It shows the involvement of various signaling components (such as EIN2, LOX2) and transcription factors (such as oresara1 or ORE1) in controlling hormonal activity during senescence. Further, the involvement of various micro RNAs (miR164, miR319) in regulating leaf senescence are discussed. Through this book, the authors throw light on all the reverse and forward genetic approaches to reveal the role of various other phytohormones regulating plant senescence and the molecular mechanisms involved. Chapters on relevant topics are contributed by experts working in the area, making this a comprehensive treatise designed to provide an in-depth analysis on the subject matter.

The scientific and economic significance of plant senescence means that much effort has been made to understand the processes involved and to devise means of manipulating them agriculturally. During the past few years there has been considerable progress in this regard, especially in the molecular, genetic and genomic aspects. Senescence has a tremendous impact on agriculture. For example, leaf senescence limits crop yield and biomass production, and contributes substantially to postharvest loss in vegetable and ornamental crops during transportation, storage and on shelves. In addition, proteins, antioxidants and other nutritional compounds are degraded during senescence. Senescing tissues also become more susceptible to pathogen infection, and some of the pathogens may produce toxins, rendering food unsafe. Mitotic senescence may also determine sizes of leaves, fruits and whole plants. This volume summarizes recent progresses in the physiology, biochemistry, cell biology, molecular biology, genomics, proteomics, and biotechnology of plant senescence. Beginning with a chapter on senescence-related terminology and our current knowledge of mitotic senescence in plants (a less well-studied area), the book focuses on post-mitotic senescence, and includes chapters addressing the senescence of leaves, flowers and fruits. Later chapters examine the development of various new biotechnologies for manipulating the senescence processes of fruit and leaves, some of which are approaching commercialization. The book is directed at researchers and professionals in plant molecular genetics, physiology and biochemistry.

Senescence Signalling and Control in Plants discusses the studies showing the importance of hormone action on developmental senescence. It shows the involvement of various signaling components (such as EIN2, LOX2) and transcription factors (such as oresara1 or ORE1) in controlling hormonal activity during senescence. Further, the involvement of various micro RNAs (miR164, miR319) in regulating leaf senescence are discussed. Through this book, the authors throw light on all the reverse and forward genetic approaches to reveal the role of various other phytohormones regulating plant senescence and the molecular mechanisms involved. Chapters on relevant topics are contributed by experts working in the area, making this a comprehensive treatise designed to provide an in-depth analysis on the subject matter. Throws light on the involvement of hormones (other than the well- known hormones cytokine and ethylene) in plant senescence Shows the underlying mechanisms on the hormonal actions during senescence Exhibits the involvement of microRNAs during this important plant developmental process

For many, the terms aging, maturation and senescence are synonymous and used interchangeably, but they should not be. Whereas senescence represents an endogenously controlled degenerative programme leading to plant or organ death, genetiC aging encompasses a wide array of passive degenerative genetiC processes driven primarily by exogenous factors (Leopold, 1975). Aging is therefore considered a consequence of genetiC lesions that accumulate over time, but by themselves do not necessarily cause death. These lesions are probably made more severe by the increase in size and complexity in trees and their attendant physiology. Thus while the withering of flower petals following pollination can be considered senescence, the loss of viability of stored seeds more clearly represents aging (Norden, 1988). The very recent book "Senescence and Aging in Plants" does not discuss trees, the most dominant group of plants on the earth. Yet both angiospermic and gymnospermic trees also undergo the above phenomena but less is known about them. Do woody plants senesce or do they just age? What is phase change? Is this synonymous with maturation? While it is now becoming recognized that there is no programmed senescence in trees, senescence of their parts, even in gymnosperms (e. g. , needles of temperate conifers las t an average of 3. 5 years), is common; but aging is a readily acknowledged phenomenon. In theory, at least, in the absence of any programmed senescence trees should -live forever, but in practice they do not.

The existing theories on the evolution of senescence assume that senescence is inevitable in all organisms. However, recent studies have shown that this is not necessarily true. A better understanding of senescence and its underlying mechanisms could have far-reaching consequences for conservation and eco-evolutionary research. This book is the first to offer interdisciplinary perspectives on the evolution of senescence in many species, setting the stage for further developments. It brings together new insights from a wide range of scientific fields and cutting-edge research done on a multitude of different animals (including humans), plants and microbes, giving the reader a complete overview of recent developments and of the controversies currently surrounding the topic. Written by specialists from a variety of disciplines, this book is a valuable source of information for students and researchers interested in ageing and life history traits and populations.