Vegetable Brassicas and Related Crucifers

Preface Brassica vegetables continue serving mankind after millennia of use as food, fodder and forage. The quiet mundanity of cabbage yards belies their botanical miracles as exponents of genotypic and phenotypic diversity and flexibility. Brassicas provide one of the finest examples of convergent evolution in the horticultural forms of the European Brassica oleracea and Oriental B. rapa. These mirror each other in a rich spectrum of fresh foodstuffs that have been selected and bred for particular regional preferences over many centuries. Alongside are numerous other taxonomic variants brought about natural genetic manipulation and polyploidy that produce oil rich and condiment crops. This book per force concentrates on the vegetable brassicas but has made great use of the science underlying the biggest world Brassica crop on an area basis, oil seed rape or canola. It is impossible to study vegetable brassicas without being influenced by B. napus, to have included it in detail would have required a much larger volume. Only very recently science has begun recognising the nutritional benefits of both vegetables and oil seed brassicas. And in comparative terms only more recently have the properties of some of the wild relatives come to the fore. The tiny weed or rock garden speciality, Arabidopsis thaliana has achieved enormous scientific clout as a model system for molecular biological studies. In coming decades it could outstrip some of the crop vegetable brasicas in economic significance. In considering the horticultural science underpinning Brassica crops I have attempted to think forward into those aspects that will be important for students who use this Book and whose working careers may have three or more decades to run. Consequently, there is an emphasis on husbandry as the key tool in pest, pathogen and physiological disorder control. Plant breeding and the potential for genetic manipulation are emphasised. The brassicas are of pivotal significance in providing wholesome and nutritious foodstuffs for our burgeoning world population and are capable of doing even greater service to mankind when tailored to use land with an elevated salt content. The view of Vegetable Brassicas as expressed here is entirely mine and I fully accept responsibility for all errors, omissions and unconventional thinking. Tribute is due however, to my very good friend Dr Michael Dickson of Cornell University, New York State USA. He has been a constantly supportive mentor during the overlong gestation of the book. His ever kindly help is greatly valued, he penned parts of Chapter 2 relating to Plant Breeding and Genetics and Sections concerned with pest and pathogen resistance in Chapter 7. Gratitude is also due to Professor Paul Williams of Wisconsin University at Madison, USA, he has offered abiding friendship, deep intellectual sustenance and a common view of science over many decades. The roots of this book are set deep in a life - time of scientific fascination in the biology of Brassica allied to their commercial production. These bind together horticultural experiences in the Thames Valley, the broad fenlands of East Anglia, the Scottish Mearns and Fife. These are topped by all too brief acquaintances with the kale yards of Europe, extensive and intensive efficiencies of the Valley Lands of California and the sheer magical diversities of Asian cropping. Founding influences in understanding the true nature of scholarship in the natural sciences based around the concept of "One Foot in the Furrow" were my trio of mentors at Wye College (then London University's Faculty of Agriculture and Horticulture). The true teachers, Professor Herbert W Miles, Dr Edward H Wilkinson and Mr Alan Jackson, entranced young minds in the early 1960s with a rich mixture of ecology, crop physiology, plant breeding and commercial instinct founded firmly in the nascent implications of Rachel Carson's Silent Spring. Committing this text to paper needed the support and encouragement of many other friends and professional colleagues. Particular gratitude goes to Professors John Watson and John Anderson, previous and current Heads of the Department of Bioscience; Mr Stewart Roy, Faculty Officer in the Faculty of Science and Professor Sir John Arbuthnott, Vice - Chancellor and Principal of the University of Strathclyde in Glasgow. Collectively they provided a haven for scholarship proofed against icy blasts of moronic barbarity. Geoffrey R Dixon 2005.