Model Plants and Crop Improvement PDF

Preface

The past two decades have seen significant research activity in model plant biology. In particular, the workhorse Arabidopsis thaliana has become a reference species for plant biologists and has taken its place in the genomic universe alongside yeast and the animal models worm, fly, zebra-fish, and mouse as well. The vision at the outset of plant molecular biology was that much of the biological, genetic, and later genomic insights gained from the dissection of this small dicot plant would prove transferable to higher plant species in general and to crop species in particular. However, because many of the world's staple crops are monocots, the age of the monocot/dicot divergence meant that this early optimism had to be tempered with the realization that a separate monocot model was probably essential. The choice fell on rice, which also enjoys a small genome size (though not quite as small as that of Arabidopsis ) and is notably a crop plant in its own right (unlike the weed Arabidopsis ), but is less well suited to model status in the context of its slow generation turnover and the large physical size of the adult plant.

Since then, the list of model species has continued to grow, capturing the uniqueness of the important legume– Rhizobium symbiosis and tackling the phenomena of perennial and juvenile characteristics of tree species. Although the given major reason for using all these models has been to simplify research, an important additional justification has always been the promise of the flow of discoveries and technologies to crop improvement. As a result, far more is now known about the biology and genetics of the models than of any single crop species (rice, of course, excluded).

The relevance of these models for crop improvement remains a horizon application that has yet to be tested adequately. In one scenario, greater use of models closely associated with respective crop breeding programs will be a winning combination because it will enable many more hypotheses to be tested than is possible using a crop species in isolation, thus streamlining discovery of solutions to crop problems. In the opposing scenario, the model research effort can be better described as expenditure rather than as investment.

The need for improvement in all crops is so urgent and the volume of information flowing from the models so large that closer associations between models and expanded crop biology programs are a priority. Therefore, as the postgenomics era dawns, it has become timely to consider achievements and failings of the model paradigm with respect to crop science and to ask how continued research in models can contribute to the goal of delivering the outputs of molecular biology to crops. We planned the present volume as a means to gather the opinions of "modelers" and "croppers," along with those working at the model–crop transition. The book includes chapters covering the application of discoveries and research in major models (i.e., Arabidopsis and rice) for crop improvement programs and provides overviews of other model species such as Medicago, Brachypodium, and Chlamydomonas and a critical assessment of their potential for understanding the molecular genetics of crops.

The editors are grateful to the contributing authors (see "Contributors" section), who not only reviewed the published research work in their area of expertise but also shared their unpublished results to bring the chapters up to date. We also appreciate their patience and cooperation in meeting deadlines and revising their manuscripts, when required. We also acknowledge the strong support of the many collaborators (see "Reviewers" section), who willingly reviewed the manuscripts and gave useful suggestions for improvement. As editors, we take responsibility for errors (we hope few in number!) that may have crept in as a result of our editorial work.

The cooperation and help received from David Fausel and John Sulzycki of CRC Press during various stages of the development and completion of this project are appreciated. Producing this book on the back of full-time research jobs has been demanding of our time, and we thank family and friends for their forbearance in putting up with these demands. RKV particularly acknowledges the help and support of his wife, Monika, who contributed directly to formatting the text, tables, and figures in several chapters of the book. The editors hope that the book will prove useful for our target audience and that readers will bring any errors or omissions to our notice, as well as offer suggestions, so that any future update in such a quickly changing field will be facilitated.