Preface

Citrus fruits are regarded as major household items in more than 100 countries around the world. The world juice industry is also dominated by citrus juices. Citriculture is the foundation for the livelihood of millions of farm and industrial workers, entrepreneurs and businesses. There is a rich endowment of knowledge and technologies developed by dedicated researchers and academics around the world which addresses the issues faced by the citrus industry worldwide. Integration and application of knowledge from different disciplines has made its impact by guiding growers and investors to grow more and better citrus. Yet, we can see that the major citrus cultivars grown in different parts of the world are not the product of systematic breeding efforts. This book is intended to provide con- solidated information on citrus breeding in the era of biotechnology which is likely to hasten the pace of variety development aimed at resolving the problems faced by grove owners growing currently available cultivars.

Citrus breeders and geneticists have pursued development of new cultivars for nearly a century. They do have clear goals to achieve. But, the traditional techniques have simply been insuffi cient to achieve the desired goals within reasonable time frames. The early researches focused on botanical and taxonomic subjects followed by interest in cytoge- netics. The knowledge base has strengthened, but the outcome, in the form of commer- cially successful varietal releases, has remained slow, with a few success stories among rootstocks and fewer among scion cultivars. The recent advances in genetics, molecular biology and biotechnology have changed the pace of citrus breeding and genetics research. New approaches allow recombination within a broader and better understood germplasm pool, and more effi cient selection methods have been developed for many traits. Progress has been also accelerated by the ease of communications via electronic media.

The scientifi c community is better organized than it was 50 years ago. The International Society of Citriculture has been holding its congresses at regular intervals since 1968. The amount of information presented on genetic improvement has grown manifold. There is hope that the fl ow of materials will follow the trends in the fl ow of information.

The idea of this book evolved from discussions held during citriculture congresses at Orlando, Florida (in 2000) and then at Agadir, Morocco (in 2004). Nearly all active citrus breeders of the world were willing to join hands to consolidate up-to-date information to accelerate citrus breeding. The subjects covered in the book are focused on citrus while

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providing information equally useful to the breeders of other tree crops. This will also help students of genetics and breeding identify appropriate applications of biotechnology in citrus breeding. While providing information on future avenues, the authors have also reviewed the past progress and achievements ensuring continuity of the subject. Several chapters include protocols for novel techniques that should facilitate their broader appli- cation by citrus breeders.

Many colleagues at CREC-Lake Alfred, where most of the editorial work was under- taken, helped in vetting the drafts. While the ideas and refereeing help from many is acknowledged, the editor takes the responsibility for errors and omissions. Patience of CABI management and staff has been a source of encouragement. Many thanks to them for doing an excellent job of compilation. This task could not have been accomplished with- out support from the Sultan Qaboos University, Muscat. It is hoped that the book will prove benefi cial to a wide range of readership.

Iqrar Ahmad Khan