Landraces possess a very large genetic base in population structure and are dynamic populations of cultivated plants with historical origin, distinct identity, and without any formal crop improvement. They are often genetically diverse, locally adapted, and associated with traditional farming systems. Resistance genes to biotic and abiotic stress factors, which are especially diversified in landraces, are of great interest to plant breeders, faced with global climate challenge. In addition, gene pools made of different landraces grown in different ecological conditions can be used for wheat breeding to enhance quality; yield and other desirable agricultural parameters. An estimated 75% of the genetic diversity of crop plants was lost in the last century due to the replacement of high yielding modern varieties. There is, thus, an urgent need to preserve existing species, not only for posterity but also as a means to secure food supply for a rising world population. In this book, we provide an overview of wheat landraces with special attention to genetic diversities, conservation, and utilization.

The papers herein are volume 1 of the proceedings of the 11th International Wheat Genetics Symposium, held in Brisbane, Australia, in 2008. The series presents the science of the genetic sciences applied to bread and durum wheats and other species.

The natural environment for plants is composed of a complex set of abiotic and biotic stresses; plant responses to these stresses are equally complex. Systems biology allows us to identify regulatory hubs in complex networks. It also examines the molecular “parts” (transcripts, proteins and metabolites) of an organism and attempts to combine them into functional networks or models that effectively describe and predict the dynamic activities of that organism in different environments. This book focuses on research advances regarding plant responses to abiotic stresses, from the physiological level to the molecular level. It highlights new insights gained from the integration of omics datasets and identifies remaining gaps in our knowledge, outlining additional focus areas for future crop improvement research. Plants have evolved a wide range of mechanisms for coping with various abiotic stresses. In many crop plants, the molecular mechanisms involved in a single type of stress tolerance have since been identified; however, in order to arrive at a holistic understanding of major and common events concerning abiotic stresses, the signaling pathways involved must also be elucidated. To date several molecules, like transcription factors and kinases, have been identified as promising candidates that are involved in crosstalk between stress signalling pathways. However, there is a need to better understand the tolerance mechanisms for different abiotic stresses by thoroughly grasping the signalling and sensing mechanisms involved. Accordingly, this book covers a range of topics, including the impacts of different abiotic stresses on plants, the molecular mechanisms leading to tolerance for different abiotic stresses, signaling cascades revealing cross-talk among various abiotic stresses, and elucidation of major candidate molecules that may provide abiotic stress tolerance in plants.

Crops experience an assortment of environmental stresses which include abiotic viz., drought, water logging, salinity, extremes of temperature, high variability in radiation, subtle but perceptible changes in atmospheric gases and biotic viz., insects, birds, other pests, weeds, pathogens (viruses and other microbes). The ability to tolerate or adapt and overwinter by effectively countering these stresses is a very multifaceted phenomenon. In addition, the inability to do so which renders the crops susceptible is again the result of various exogenous and endogenous interactions in the ecosystem. Both biotic and abiotic stresses occur at various stages of plant development and frequently more than one stress concurrently affects the crop. Stresses result in both universal and definite effects on plant growth and development. One of the imposing tasks for the crop researchers globally is to distinguish and to diminish effects of these stress factors on the performance of crop plants, especially with respect to yield and quality of harvested products. This is of special significance in view of the impending climate change, with complex consequences for economically profitable and ecologically and environmentally sound global agriculture. The challenge at the hands of the crop scientist in such a scenario is to promote a competitive and multifunctional agriculture, leading to the production of highly nourishing, healthy and secure food and animal feed as well as raw materials for a wide variety of industrial applications. In order to successfully meet this challenge researchers have to understand the various aspects of these stresses in view of the current development from molecules to ecosystems. The book will focus on broad research areas in relation to these stresses which are in the forefront in contemporary crop stress research.

This volume will be the only existing single-authored book offering a science-based breeder’s manual directed at breeding for water-limited environments. Plant breeding is characterized by the need to integrate information from diverse disciplines towards the development and delivery of a product defines as a new cultivar. Conventional breeding draws information from disciplines such as genetics, plant physiology, plant pathology, entomology, food technology and statistics. Plant breeding for water-limited environments and the development of drought resistant crop cultivars is considered as one of the more difficult areas in plant breeding while at the same time it is becoming a very pressing issue. This volume is unique and timely in that it develops realistic solutions and protocols towards the breeding of drought resistant cultivars by integrating knowledge from environmental science, plant physiology, genetics and molecular biology.

A close examination of current research on abiotic stresses in various plant species The unpredictable environmental stress conditions associated with climate change are significant challenges to global food security, crop productivity, and agricultural sustainability. Rapid population growth and diminishing resources necessitate the development of crops that can adapt to environmental extremities. Although significant advancements have been made in developing plants through improved crop breeding practices and genetic manipulation, further research is necessary to understand how genes and metabolites for stress tolerance are modulated, and how cross-talk and regulators can be tuned to achieve stress tolerance. Molecular Plant Abiotic Stress: Biology and Biotechnology is an extensive investigation of the various forms of abiotic stresses encountered in plants, and susceptibility or tolerance mechanisms found in different plant species. In-depth examination of morphological, anatomical, biochemical, molecular and gene expression levels enables plant scientists to identify the different pathways and signaling cascades involved in stress response. This timely book: Covers a wide range of abiotic stresses in multiple plant species Provides researchers and scientists with transgenic strategies to overcome stress tolerances in several plant species Compiles the most recent research and up-to-date data on stress tolerance Examines both selective breeding and genetic engineering approaches to improving plant stress tolerances Written and edited by prominent scientists and researchers from across the globe Molecular Plant Abiotic Stress: Biology and Biotechnology is a valuable source of information for students, academics, scientists, researchers, and industry professionals in fields including agriculture, botany, molecular biology, biochemistry and biotechnology, and plant physiology.