Over recent years, progress in micropropagation has not been as rapid as many expected and, even now, relatively few crops are produced commercially. One reason for this is that the biology of material growing in vitro has been insufficiently understood for modifications to standard methods to be made based on sound physiological principles. However, during the past decade, tissue culture companies and others have invested considerable effort to reduce the empirical nature of the production process. The idea of the conference `Physiology, Growth and Development of Plants and Cells in Culture' (Lancaster, 1992) was to introduce specialists in different areas of plant physiology to micropropagators, with the express aims of disseminating as wide a range of information to as large a number of participants as possible, and beginning new discussions on the constraints and potentials affecting the development of in vitro plant production methods. This book is based on presentations from the conference and has been divided into two main sections, dealing with either aspects of the in vitro environment -- light, nutrients, water, gas -- or with applied aspects of the culture process -- morphogenesis, acclimation, rejuvenation, contamination.

This book discusses; somaclonal variation in crop improvement, the role of tissue culture in rapid clonal propagation and production of pathogen-free plant, protoplasts in crop improvement, cell selection and long-term high-frequency regeneration of cereals and legumes, agrobacteria-mediated gene transformation and vectors for gene cloning in plants, and plant frost injury and its management.

The main objective of this book is to bring all the research activities of mutation breeding in one umbrella.

Haploid plants have the gametophytic number of chromosomes. They are of great importance, especially in studies on the induction of muta tions and also for the production of homozygous plants, they are needed in large numbers. The conventional methods employed by plant breeders for their production are cumbersome, time-consuming, laborious and rather inefficient. Sometimes it may take years to produce a pure line. However, with the introduction of in vitro techniques, especially anther culture for the induction of androgenesis, it has become increasingly evi dent that these methods considerably accelerate the production of haploids for plant breeding programs. During the last decade, in vitro-produced haploids have been incor porated into breeding programs of many agricultural crops, and positive results have been obtained especially with rice, wheat, potato, barley, maize, asparagus, sunflower, brassica, tobacco, etc. Among these, rice and wheat are the best examples in which a number of improved varieties have been released. In wheat, the breeding cycle can be shortened by three or four generations when the pollen haploid breeding method is used instead of conventional cross-breeding. The release of the wheat varieties Jinghua 1 and Florin is a typical example of what can be achieved with other crops. Taking these developments into considera tion, the present volume, Haploids in Crop Improvement I, was compil ed.

Progress in the field of plant cell and tissue culture has made this area of research one of the most dynamic and promising not only in plant physiology, cell biology and genetics but also in agriculture, forestry, horticulture and industry. Studies with plant cell cultures clearly have bearing upon a variety of problems as yet unsolved in basic and applied research. This was the compelling reason for assembling such a comprehensive source of information to stimulate students, teachers, and research workers. This book comprises 34 articles on regeneration of plants, vegetative propagation and cloning; haploids; cytology, cytogenetics and plant breeding; protoplasts, somatic hybridization and genetic engineering; plant pathology; secondary products and a chapter on isoenzymes, radiobiology, and cryobiology of plant cells. Particular attention has been paid to modern , fast-growing and fascinating disciplines - e.g. the induction of haploids, somatic hybridization and genetic manipulation by protoplast culture, which possess an enormous potential for plant improvement.