Genetic Resources, Chromosome Engineering, and Crop Improvement: Vegetable Crops, Volume 3 PDF

Preface

Major cereals, grain legumes, oilseeds, and vegetable crops have always been an integral part of human civilization since time immemorial; they are also a primary food source for the world population. These crops are a rich source of carbohydrates (cereals), proteins (grain legumes), oils and fats (oilseed crops), and vitamins and minerals (vegetable crops). Vegetable crops have a unique place among domesticated crops because they are enriched in minerals, vitamins and antioxidants. Fresh vegetables are low in fat and sodium. Vegetables are consumed raw as well as cooked by both the vegetarian and non-vegetarian populations of the world. Moderate consumption of vegetables and fruits with cereals and beans reduces the risk of cancer, stress, diabetes, Alzheimer's, heart disease, and stroke (http://www.cncplan.com/vitamins.htm). Lycopene, found in tomato, is a powerful protector of prostrate, breast, digestive tract, cervix, bladder, and skin against cancer. Onion is a rich source of quercetin, a potent antioxidant linked to preventing stomach cancer. Daily consumption of a half raw onion lowers low density lipoprotein (LDL) cholesterol and raises beneficial high density lipoprotein (HDL) cholesterol by as much as 30%. Garlic, consumed raw, has antibacterial, antifungal, and anticancer properties. Garlic also has a blood-thinning quality. It lowers blood cholesterol, reduces high blood pressure, boosts the immune system, elevates mood, and has a calming effect in humans. Brassicas are effective in fighting cancer and are a rich source of vitamins (B, C, and E), iron, folate, zinc, potassium, thiamine, beta carotene, and fiber. Potato contains complex carbohydrates, protein, fiber, and provides vitamins B and C, iron and potassium (http://prostratecanceralternatives.com). Consequently, researchers around the globe are relentlessly examining and breeding vegetable crops for their superior nutritional quality and quantity, increased yield, and disease resistance. Despite their nutritional superiority and profound importance to human health, vegetable crops have received less attention toward needed genetic improvement than they deserve when compared with genetic research on cereals, grain legumes, and oilseeds. However, recently in progress is a new role for vegetable crops: their increasing use as ornamental and decorative plants (e.g. special forms and varieties of amaranth, crucifers, cucurbits, wild alliums, tomato, pepper, and eggplant). These new trends clearly demonstrate that vegetables and related crops may contribute not only to human nutrition but also to the improvement of human environment and quality of life.

Vegetable crops include crucifers (cabbage, cauliflower, kale, and brussels sprouts), tuber bulbs and root crops (potatoes, onions, garlic, turnip, leek, carrot, beet root, and radish), vegetable fruits (tomato, eggplant, okra, and cucurbits), salad crops (spinach, lettuce, amaranth, and celery), and protein-rich grain legumes (common bean, cowpea, faba bean, chickpea, and mungbean). Beans and peas have been excluded from this volume on Vegetable Crops because they have been included in the volume Grain Legumes of this series.

The majority of the vegetable crops originated in the Old World, particularly in Asia, while potato and tomato originated in the New World—South America. Today, potato and tomato are important vegetables throughout the world. They are considered a miracle gift of the New World and are grown worldwide in a wide range of agro-eco-climatic conditions on a commercial scale as well as on a small scale, often known as "kitchen gardening." Potato production alone accounts for 44% of all the vegetable crops production listed by the Food and Agriculture Organization (FAO) (http://faostat.fao.org). It is ranked as the fourth most important food crop of the world. Furthermore, more than one-third of all the potatoes are now grown in the developing countries (http://www.cipotato.org).

The intensive varietal improvements of vegetable crops for high yield and improved nutritional quality are primary breeding objectives of various national and international programs. Three international centers for vegetable crops have been established: (1) The International Potato Center [Centro Internacional de la Papa (CIP)] was founded in 1971 in Lima, Peru (http://www.cipotato. org); its primary mandate was to deliver high-yielding potatoes. (2) The Asian Vegetable Research and Development Center (AVRDC) was established in 1971 in Shanhua, Taiwan (www.avrdc.org); its mandate is to improve tomato, brassicas, alliums, cucurbits, peppers, eggplant, okra, and legumes including edamame (edible vegetable soybean). (3) Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia (www.ciat.cgiar.org) works on beans as one of its primary mandates (described in Grain Legumes, Volume 1 of this series), and also works on sweet potatoes. The Indian Institute of Vegetable Research (IIVR) in Varanasi, Uttar Pradesh, India (www.icar.org.in) is a national institute; it concentrates on multidisciplinary research approaches for the improvement of the major vegetable crops grown in India. These and other centers around the world collect, maintain and preserve germplasm resources as potential sources of genes for high yield, resistance to various biotic and abiotic stresses, and for improving nutritional, storage, and shelf life qualities. In Europe, Warwick Horticulture Research Station (HRI) (a part of the University of Warwick, Warwick, UK; formerly known as National Vegetable Research Station (NVRS) and then HRI in Wellesbourne, UK) is a leading world center of vegetable research and breeding. Since its days in Wellesbourne in the middle of the twentieth century, this institution has contributed substantially to progress in several areas (breeding, plant protection, and disease management, plant nutrition and physiology, seed and growing technology, germplasm preservation and characterization, and biotechnology of vegetable sciences).

Most genetic improvements of vegetable crops have been accomplished by conventional breeding assisted by germplasm resources, cytogenetics, plant pathology, entomology, agronomy, cell and tissue cultures, and molecular biology. Because there is no consolidated account of germplasm resources, cytogenetic manipulations, biotechnological approaches, and breeding of vegetable cops, it was important to bring out this book, Volume 3 in the series Genetic Resources,Chromosome Engineering, and Crop Improvement. World-renowned scientists were invited to contribute chapters on the vegetable crops of their expertise. This volume consists of 11 chapters dealing with vegetable crops of great economic importance for the developed and the developing countries of the world. These chapters give comprehensive and authoritative accounts of genetic resources and their utilization for improving yields, disease and pest resistance, other agronomic traits, and nutritive quality of the most widely grown and consumed vegetables.

The introductory chapter summarizes the landmark research carried out in ten vegetable crops, giving information on germplasm availability for breeding for high yields and improved nutritional quality. Each of the subsequent chapters (2 through 11) deals, respectively, with one of the ten crops: potato, tomato, brassicas, okra, capsicum, alliums, cucurbits, lettuce, eggplant and carrot. Each chapter provides a comprehensive account of the origin of the crop, its genetic resources in various gene pools, basic and molecular cytogenetics, conventional breeding, and the modern tools of molecular genetics and biotechnology.

Appropriate germplasm collections can be an excellent source for genetic enhancement of various traits in vegetative crops and for broadening their genetic base. The genetic base of major vegetable crops is extremely narrow. The classical example of a narrow genetic base is the Great Irish Potato Famine (1845–1847) caused by a fungus, the potato blight [Phytophothora infestans (Mont.) de Bary] that ruined almost 100% of the potato crop of Ireland. Irish farmers were cultivating white potato introduced directly from the Andean Mountains (http://www.american. edu). In view of the narrow genetic base of vegetable crops, three gene pools have now been identified by the scientists: primary (GP-1), secondary (GP-2), and tertiary (GP-3) for each crop. The recommendation is to the use GP-2 and GP-3 resources in producing widely adapted varieties. Utilization of these resources in producing high-yielding cultivars, resistant to abiotic and biotic stresses, and with improved nutritional qualities is discussed in this book.

Each chapter has been written by one or more experts in the field. I am extremely grateful to all the authors for their outstanding contributions, and to the reviewers of all the chapters. I have been fortunate to know them both professionally and personally, and our communication has been very cordial and friendly. I am particularly indebted to Henry De Jong, Govindjee, Mike Havey, Bob Jarret, Alesˇ Lebeda, Joseph Nicholas, Carlos Quiros, Phil Simon, and Richard Veilleux for their comments and suggestions on some of the chapters. I am profoundly grateful to Alesˇ Lebeda and Govindjee for their constructive and invaluable suggestions for the composition of the dedication for this volume. Finally, I thank Steven G. Pueppke, former associate dean and research director at the University of Illinois, Urbana, for his support and encouragement.

This book is intended for scientists, professionals, and graduate students whose interests center upon genetic improvement of crops in general, and major vegetable crops in particular. This book is meant to be a reference for plant breeders, taxonomists, cytogeneticists, agronomists, molecular biologists, food technologists, and biotechnologists. Graduate-level students in these disciplines, with an adequate background in genetics, as well as other researchers interested in biology and agriculture will also find this volume a worthwhile reference. I sincerely hope that the information assembled in this book will help in the much-needed genetic amelioration of vegetables crops to feed the ever-expanding global population. I anticipate that this book will enhance awareness regarding nutritive values of vegetables, thus preventing malnutrition worldwide. I can be reached at [email protected]

I end this Preface with a philosophical quotation from Albert Einstein (1879–1955)