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Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L.



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Biology and Chemistry of Jerusalem Artichoke Helianthus tuberosus L.



Stanley J. Kays and Stephen F. Nottingham



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CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2008 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed in the United States of America on acid-free paper 10 9 8 7 6 5 4 3 2 1 International Standard Book Number-10: 1-4200-4495-8 (Hardcover) International Standard Book Number-13: 978-1-4200-4495-9 (Hardcover) This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission, and sources are indicated. A wide variety of references are listed. Reasonable eﬀorts have been made to publish reliable data and information, but the author and the publisher cannot assume responsibility for the validity of all materials or for the consequences of their use. No part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microﬁlming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright.com (http:// www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC) 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-proﬁt organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identiﬁcation and explanation without intent to infringe. Library of Congress Cataloging-in-Publication Data Kays, Stanley J. Biology and chemistry of Jeruslaem artichoke : helianthus tuberosus L. / author(s), Stanley J. Kays and Stephen F. Nottingham. p. cm. Includes bibliographical references and index. ISBN-13: 978-1-4200-4495-9 (alk. paper) ISBN-10: 1-4200-4495-8 (alk. paper) 1. Jerusalem artichoke. I. Nottingham, Stephen, 1960- II. Title. QK495.C74K39 2007 583’.99--dc22 Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com



2007007715



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Dedication In memory of Margaret Nottingham and Raymond and Charlotte Kays, enthusiastic gardeners and lovers of plants.



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Contents Chapter 1



Introduction: An Underutilized Resource ....................................................................1



References ..........................................................................................................................................5



Chapter 2



Nomenclature, Origin, and History..............................................................................7



2.1 Nomenclature for Helianthus tuberosus L............................................................................7 2.2 Origin ...................................................................................................................................16 2.3 History .................................................................................................................................18 References ........................................................................................................................................22



Chapter 3



Classification, Identification, and Distribution ..........................................................29



3.1 Classification........................................................................................................................29 3.2 Identification ........................................................................................................................31 3.3 Distribution ..........................................................................................................................33 References ........................................................................................................................................33



Chapter 4 4.1



Plant Morphology and Anatomy................................................................................35



Morphology .........................................................................................................................36 4.1.1 Stems and Branches ..............................................................................................36 4.1.1.1 Stem/Plant Height .................................................................................36 4.1.1.2 Stem Gravitropic Response...................................................................36 4.1.1.3 Stem Number.........................................................................................36 4.1.1.4 Stem Diameter.......................................................................................36 4.1.1.5 Stem Branching .....................................................................................36 4.1.1.6 Stem Color.............................................................................................37 4.1.2 Leaves....................................................................................................................37 4.1.2.1 Leaf Shape.............................................................................................37 4.1.2.2 Shape at the Leaf Tip ............................................................................37 4.1.2.3 Shape at the Leaf Base..........................................................................37 4.1.2.4 Serration of Margins .............................................................................37 4.1.2.5 Leaf Size................................................................................................38 4.1.2.6 Leaf Number .........................................................................................38 4.1.2.7 Leaf Angle .............................................................................................38 4.1.2.8 Leaf Coloration .....................................................................................39 4.1.2.9 Bract at the Base of the Leaf ................................................................39 4.1.2.10 Phyllotaxy..............................................................................................39 4.1.3 Inflorescence..........................................................................................................39 4.1.3.1 Size of the Inflorescence .......................................................................41 vii



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4.1.3.2 Number of Inflorescences .....................................................................41 4.1.3.3 Number of Disk Flowers per Inflorescence..........................................41 4.1.3.4 Number of Ray Flowers per Inflorescence...........................................41 4.1.3.5 Ligule Shape..........................................................................................41 4.1.3.6 Ligule Density .......................................................................................41 4.1.4 Fruit .......................................................................................................................41 4.1.5 Rhizomes ...............................................................................................................42 4.1.5.1 Length....................................................................................................43 4.1.5.2 Diameter ................................................................................................43 4.1.5.3 Number ..................................................................................................43 4.1.6 Tubers ....................................................................................................................43 4.1.6.1 External Color .......................................................................................43 4.1.6.2 Internal Color ........................................................................................43 4.1.6.3 Shape .....................................................................................................44 4.1.6.4 Tuber Size..............................................................................................44 4.1.6.5 Number of Internodes ...........................................................................44 4.1.6.6 Surface Topography...............................................................................44 4.1.6.7 Depth of Eyes........................................................................................44 4.1.7 Subterranean Stem ................................................................................................44 4.1.8 Roots......................................................................................................................44 4.2 Anatomy...............................................................................................................................45 4.2.1 Stomata Size and Density .....................................................................................45 4.2.2 Trichomes ..............................................................................................................45 4.2.2.1 Stems .....................................................................................................45 4.2.2.2 Leaves ....................................................................................................46 4.2.2.3 Flowers ..................................................................................................47 4.2.3 Flowers ..................................................................................................................47 4.2.4 Calcium Oxalate Crystals in Floral Organs..........................................................47 4.2.5 Tuber Storage Parenchyma Ultrastructure............................................................48 References ........................................................................................................................................49



Chapter 5 5.1



5.2 5.3



5.4 5.5 5.6



5.7



Chemical Composition and Inulin Chemistry ...........................................................53



Chemical Composition ........................................................................................................53 5.1.1 Tuber Composition................................................................................................53 5.1.2 Aerial Plant Parts ..................................................................................................57 Occurrence of Inulin in Plants ............................................................................................58 Composition, Structure, and Properties of Inulin and Inulin Oligomers ...........................61 5.3.1 Crystal Structure of Inulin Oligomers ..................................................................61 5.3.2 Structure in an Aqueous Solution .........................................................................61 5.3.3 Properties of Inulin ...............................................................................................62 Analysis of Inulin Composition ..........................................................................................62 Inulin Extraction, Isolation, Purification, Fractionation, Drying, and Storage ..................64 Sources of Inulin .................................................................................................................65 5.6.1 Traditional Plant Sources ......................................................................................65 5.6.2 Transgenic Crops...................................................................................................65 5.6.3 Synthesis Using Microorganisms..........................................................................66 Uses for Native and Fractionated Inulin .............................................................................66 5.7.1 Native Inulin..........................................................................................................66 5.7.1.1 Bulking Agents ......................................................................................66



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5.7.1.2 Bakery and Dairy Products ...................................................................67 5.7.1.3 Fructose and Short-Chain Fructans.......................................................67 5.7.1.4 Nutraceutical Supplements....................................................................67 5.7.1.5 Medical Applications.............................................................................68 5.7.2 Inulin Fractionated by Degree of Polymerization ................................................68 5.7.2.1 Fat Substitutes .......................................................................................68 5.8 Microbial and Enzymatic Modification of Inulin ...............................................................69 5.8.1 Hydrolysis .............................................................................................................69 5.8.1.1 Complete Hydrolysis: Fructose Syrups ................................................69 5.8.1.2 Partial Hydrolysis: Inulin Oligomers ....................................................70 5.8.2 Fermentation..........................................................................................................71 5.8.2.1 Ethanol...................................................................................................71 5.8.2.2 Butanol and Acetone .............................................................................72 5.8.2.3 Other Fermentation Products ................................................................72 5.8.3 Cyclization.............................................................................................................73 5.8.3.1 Cyclic Inulooligosaccharides ................................................................73 5.8.3.2 Fructose Dianhydrides...........................................................................73 5.9 Chemical Modification of Inulin.........................................................................................75 5.9.1 Reduction...............................................................................................................75 5.9.2 Hydrolysis .............................................................................................................75 5.9.2.1 Hydroxymethylfurfural..........................................................................75 5.9.2.2 Mannitol.................................................................................................75 5.9.3 Hydrogenolysis......................................................................................................76 5.9.4 Esterification..........................................................................................................76 5.9.5 Methylated Inulin ..................................................................................................77 5.9.6 Inulin Carbonates ..................................................................................................77 5.9.7 O-(Carboxymethyl)inulin ......................................................................................77 5.9.8 Inulin Ethers ..........................................................................................................78 5.9.9 Dialdehyde-Inulin..................................................................................................78 5.9.10 Inulin Carbamates .................................................................................................79 5.9.11 Inulin–Amino Acids ..............................................................................................79 5.9.12 O-(Cyanoethyl)inulin ............................................................................................80 5.9.13 O-(3-Amino-3-oxopropyl)inulin ...........................................................................80 5.9.14 O-(Carboxyethyl)inulin .........................................................................................80 5.9.15 O-(3-Hydroxyimino-3-aminoproply)inulin...........................................................80 5.9.16 O-(Aminopropyl)inulin .........................................................................................82 5.9.17 Stearoyl Amide and N-Carboxymethylaminopropylated Inulin...........................82 5.9.18 Derivatives of O-(Aminopropyl)inulin .................................................................82 5.9.19 Cycloinulohexaose Derivatives .............................................................................82 5.9.20 Oxidation ...............................................................................................................82 5.9.20.1 Selective Oxidation of the Primary Hydroxyl Group...........................83 5.9.20.2 Glycolic Oxidation ................................................................................84 5.9.21 Alkoxylated Inulin ................................................................................................84 5.9.22 Inulin Phosphates ..................................................................................................85 5.9.23 Complexing Agents ...............................................................................................85 5.9.24 Cationic Modification............................................................................................85 5.9.25 Cross-Linked Inulin ..............................................................................................85 References ........................................................................................................................................86



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Chapter 6



Value in Human and Animal Diets ............................................................................97



6.1



In Human Diets ...................................................................................................................97 6.1.1 Inulin and Obesity.................................................................................................99 6.1.2 Inulin and Diabetes Mellitus...............................................................................100 6.1.3 Probiotics, Prebiotics, and Bifidobacteria...........................................................101 6.1.4 Inulin and Bone Health.......................................................................................103 6.1.5 Blood Lipids and Heart Disease .........................................................................104 6.1.6 The Immune System and Cancer Prevention .....................................................105 6.1.7 Bowel Function ...................................................................................................106 6.1.8 Digestive Downsides ...........................................................................................106 6.2 In Animal Diets .................................................................................................................108 6.2.1 Forage ..................................................................................................................108 6.2.2 Silage and Feed Pellets .......................................................................................112 6.2.3 Probiotic Feed Supplements ...............................................................................113 6.2.3.1 Pigs ......................................................................................................114 6.2.3.2 Ruminants............................................................................................115 6.2.3.3 Poultry .................................................................................................115 6.2.3.4 Domestic Animals ...............................................................................116 References ......................................................................................................................................116



Chapter 7



Biomass and Biofuel ................................................................................................127



7.1 7.2 7.3



Biomass..............................................................................................................................127 Direct Combustion.............................................................................................................129 Biological Conversion .......................................................................................................130 7.3.1 Ethanol.................................................................................................................130 7.3.2 Biogas (Methane) ................................................................................................138 References ......................................................................................................................................142



Chapter 8 8.1 8.2 8.3 8.4 8.5 8.6



8.7 8.8 8.9



Genetic Resources, Breeding, and Cultivars............................................................149



Breeding Programs ............................................................................................................149 Cytology.............................................................................................................................151 Interspecific Hybrids..........................................................................................................151 Controlled Crosses.............................................................................................................153 Traditional Breeding..........................................................................................................153 Breeding Techniques .........................................................................................................153 8.6.1 Controlled Crosses in the Greenhouse ...............................................................154 8.6.2 Natural Open-Pollinated Crosses Using Polycross Nurseries............................154 8.6.3 Isolated Pair Crosses ...........................................................................................155 Flowering Time Manipulation...........................................................................................155 Irradiation...........................................................................................................................155 Selection Criteria ...............................................................................................................157 8.9.1 Yield ....................................................................................................................157 8.9.2 Tuber Size............................................................................................................158 8.9.3 Smoothness of Tuber Surface .............................................................................158 8.9.4 Inulin Quantity and Quality ................................................................................158 8.9.5 Rhizome Length ..................................................................................................158 8.9.6 Plant Height, Stem Number, and Branching ......................................................158



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8.9.7 Maturity Date ......................................................................................................159 8.9.8 Disease Resistance ..............................................................................................159 8.9.9 Forage Quality.....................................................................................................159 8.10 Selection Sequence ............................................................................................................159 8.11 Heritability of Important Traits .........................................................................................160 8.12 Transgenic Plants...............................................................................................................160 8.12.1 Jerusalem Artichoke as a Source of Genes ........................................................160 8.12.2 Transformation of Jerusalem Artichoke .............................................................164 8.13 Genetic Resources .............................................................................................................165 8.13.1 Canada .................................................................................................................165 8.13.2 U.S. ......................................................................................................................165 8.13.3 Central and South America.................................................................................173 8.13.4 Germany, Austria, Slovenia, and Switzerland ....................................................173 8.13.5 France and Spain.................................................................................................173 8.13.6 Denmark, Finland, Iceland, Norway, and Sweden.............................................176 8.13.7 Russian Federation ..............................................................................................180 8.13.8 Ukraine and Azerbaijan.......................................................................................180 8.13.9 Bulgaria, Hungary, and Romania........................................................................181 8.13.10 Czech Republic, Slovakia, and Serbia and Montenegro ....................................181 8.13.11 Asia and Australasia............................................................................................185 8.14 Cultivars and Clones..........................................................................................................185 8.14.1 Synonyms, Duplication, and Confusion in Collections .....................................185 8.14.2 Directory of Cultivars, Clones, and Wild-Collected Material, with Synonyms, and Notes on Origin, Characteristics, Availability in Collections, and References to Relevant Studies, with Selected Yield Data............................................................................................................187 References ......................................................................................................................................238



Chapter 9



Propagation ...............................................................................................................251



9.1



Tubers ................................................................................................................................251 9.1.1 Tuber Dormancy..................................................................................................251 9.1.1.1 Control of Dormancy ..........................................................................252 9.1.1.2 Initial Events after the Fulfillment of Dormancy ...............................253 9.2 Rhizomes ...........................................................................................................................254 9.3 Tissue Culture....................................................................................................................255 9.4 Slips ...................................................................................................................................259 9.5 Cuttings..............................................................................................................................260 9.6 Seed....................................................................................................................................260 References ......................................................................................................................................261



Chapter 10 Developmental Biology, Resource Allocation, and Yield........................................269 10.1



Developmental Stages .......................................................................................................271 10.1.1 Emergence and Canopy Development................................................................272 10.1.1.1 Stems ...................................................................................................272 10.1.1.2 Branches ..............................................................................................272 10.1.1.3 Leaves ..................................................................................................273 10.1.2 Rhizome Formation.............................................................................................276 10.1.3 Tuberization.........................................................................................................277



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10.2



10.3



10.4 10.5 10.6 10.7



10.8



10.9 10.10 10.11 10.12



10.13



10.14



Biology and Chemistry of Jerusalem Artichoke: Helianthus tuberosus L.



10.1.3.1 Initiation...............................................................................................277 10.1.3.2 Tuber Formation ..................................................................................280 10.1.3.3 Tuber Bulking......................................................................................281 10.1.3.4 Dormancy ............................................................................................281 10.1.3.5 Initial Events after the Fulfillment of Dormancy ...............................282 10.1.3.6 Cold Tolerance.....................................................................................282 10.1.4 Flowering.............................................................................................................282 10.1.4.1 Flower Initiation ..................................................................................282 10.1.4.2 Flower Development ...........................................................................285 10.1.4.3 Seed Development and Dormancy......................................................286 10.1.5 Senescence...........................................................................................................287 Photosynthesis ...................................................................................................................289 10.2.1 Light ....................................................................................................................290 10.2.2 Maximum Assimilation Rate ..............................................................................292 Respiration .........................................................................................................................294 10.3.1 Dark Respiration .................................................................................................294 10.3.2 Cyanide-Resistant Respiration ............................................................................294 10.3.3 Respiratory Rate..................................................................................................295 10.3.4 Respiratory Patterns ............................................................................................295 10.3.5 Photorespiration...................................................................................................298 Assimilate Allocation Strategy..........................................................................................298 Carbon Transport ...............................................................................................................300 Sink Strength in Relation to Allocation............................................................................301 Assimilate Allocation and Redistribution .........................................................................303 10.7.1 Dry Matter...........................................................................................................304 10.7.2 Carbon .................................................................................................................305 10.7.3 Nutrients ..............................................................................................................308 Fructan Metabolism...........................................................................................................309 10.8.1 Fructan Polymerization/Depolymerization Reactions ........................................314 10.8.2 Enzymes ..............................................................................................................317 10.8.2.1 Sucrose:Sucrose 1-Fructosyl Transferase ...........................................317 10.8.2.2 Fructan:Fructan 1-Fructosyl Transferase ............................................319 10.8.2.3 Fructan 1-Exohydrolase ......................................................................319 10.8.3 Regulation............................................................................................................319 10.8.4 Changes in Polymerization during Development...............................................320 10.8.5 Effect of Depolymerization on Potential Uses of Inulin....................................321 Additional Metabolic Pathways ........................................................................................321 Molecular Genetics............................................................................................................324 Yield...................................................................................................................................325 Growth Analysis and Modeling ........................................................................................325 10.12.1 Distribution of Growth and Reallocation of Compounds ..................................326 10.12.2 Leaf Area.............................................................................................................327 10.12.3 Biological Yield and Harvest Index....................................................................331 10.12.4 Crop Growth and Assimilation Rates .................................................................332 Environmental Factors Affecting Yield .............................................................................333 10.13.1 Radiation .............................................................................................................333 10.13.2 Temperature.........................................................................................................334 10.13.3 Photoperiod .........................................................................................................335 10.13.4 Precipitation.........................................................................................................336 10.13.5 Wind ....................................................................................................................336 Production Factors Affecting Yield ...................................................................................337



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10.14.1 Soil Type and Treatment .....................................................................................337 10.14.2 Irrigation ..............................................................................................................338 10.14.3 Plant Population Density.....................................................................................339 10.14.4 Length of Growing Season .................................................................................340 10.14.5 Weeds ..................................................................................................................341 10.14.6 Growth Regulators ..............................................................................................341 References ......................................................................................................................................344



Chapter 11 Pollinators, Pests, and Diseases ...............................................................................365 11.1 11.2



Insect Pollinators ...............................................................................................................365 Insect Pests ........................................................................................................................365 11.2.1 Sunflower Beetle .................................................................................................367 11.2.2 Sunflower Budworm ...........................................................................................367 11.2.3 Sunflower Stem Weevil .......................................................................................369 11.2.4 Sunflower Maggot ...............................................................................................370 11.2.5 Banded Sunflower Moth .....................................................................................370 11.2.6 Sunflower Moth...................................................................................................370 11.2.7 Sunflower Seed Maggot ......................................................................................370 11.2.8 Grasshoppers .......................................................................................................370 11.2.9 Leafworms and Cutworms ..................................................................................371 11.2.10 Aphids .................................................................................................................371 11.3 Mollusks, Nematodes, and Other Pests ............................................................................372 11.4 Fungal, Bacterial, and Viral Diseases ...............................................................................372 11.4.1 Rust......................................................................................................................374 11.4.2 Southern Wilt/Blight/Collar Rot .........................................................................375 11.4.3 Powdery Mildew .................................................................................................375 11.4.4 Sclerotinia Wilt/Rot.............................................................................................376 11.4.5 Apical Chlorosis..................................................................................................377 11.4.6 Tuber Rots ...........................................................................................................377 References ......................................................................................................................................379



Chapter 12 Agronomic Practices ................................................................................................383 12.1 12.2 12.3



Planting Date .....................................................................................................................383 Planting ..............................................................................................................................384 Weed Control .....................................................................................................................385 12.3.1 Control of Weeds in Jerusalem Artichokes ........................................................385 12.3.2 Control of Jerusalem Artichoke in Subsequent Crops .......................................386 12.3.2.1 Chemical Control ................................................................................387 12.3.2.2 Mechanical Control .............................................................................389 12.3.2.3 Crop Rotation ......................................................................................389 12.3.2.4 Novel Control Techniques...................................................................390 12.4 Fertilization........................................................................................................................390 12.5 Irrigation ............................................................................................................................392 12.6 Harvesting and Handling...................................................................................................395 12.6.1 Harvest of Tubers ................................................................................................395 12.6.2 Harvest of the Aboveground Plant Parts ............................................................396 References ......................................................................................................................................396



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Chapter 13 Storage ......................................................................................................................401 13.1 Storage Options .................................................................................................................401 13.2 Storage Conditions ............................................................................................................402 13.3 Storage Losses ...................................................................................................................402 13.4 Alterations in Composition during Storage ......................................................................403 13.5 Controlled Atmosphere Storage ........................................................................................404 13.6 Irradiation...........................................................................................................................404 References ......................................................................................................................................405



Chapter 14 Economics.................................................................................................................407 14.1 Crop Production and Storage ............................................................................................407 14.2 Biofuel Production.............................................................................................................410 14.3 Inulin..................................................................................................................................416 14.4 Future Prospects for Utilizing Jerusalem Artichoke.........................................................417 References ......................................................................................................................................420



Appendix .......................................................................................................................................423 Patents Relating to Jerusalem Artichoke .......................................................................................423 Medical and Veterinary Applications.............................................................................................423 Food, Drink, and Nutraceutical Applications................................................................................425 Animal Feed Applications .............................................................................................................449 Nonfood Industrial Applications....................................................................................................451 Genetic Manipulation and Biotechnology.....................................................................................454 Cultivation and Plant Breeding......................................................................................................457



Index ..............................................................................................................................................461



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Preface Helianthus tuberosus is in its own right a fascinating species from the standpoint of plant biology. Superimposed on this is an unusually colorful history, common names (Jerusalem artichoke and topinambour) that have virtually nothing to do with the plant, and unique biological and chemical properties that distinguish it from other crops. The plant has been and continues to be far more appreciated in Europe than in the United States, where it originated. Indicative of its popularity is the fact that there have been approximately 35 monographs and books published on the crop since the first in 1789, predominantly in French, German, and Russian, with the last major book being in Hungarian by I’So in 1955. While modest compared to the major field crops, there is a wealth of scientific publications on the Jerusalem artichoke that has increased progressively from approximately 400 titles in 1932 to 1300 in 1957 to over several thousand today. Our objective with this book was to summarize our current understanding of the basic biology and chemistry of this unique crop. We have cited a diverse and representative cross section of publications, with the intent of providing those interested in delving further into this underexploited resource ready access to the literature and patents. Regrettably, due to limited resources for translations, we have not cited as many Eastern European contributions as we would have liked, some of which are by scientists who were pioneers in Jerusalem artichoke research. It has been over 50 years since the last major textbook on the species, and it is our hope that the information provided will spur additional interest and further development. The authors acknowledge a number of individuals who have been instrumental in developing the information for this work, in particular Betty Schroeder, who collected and organized reprints of the literature in addition to coordinating a number of research projects over the years. We also acknowledge Drs. Gerard Soja and Chris Stevens for reviewing sections of the text and Tatyana Gavrilenko, Yuriy Posudin, Zana Somda, and Marie-Michele Pratt for assisting with translations. We also acknowledge Will Bonsall and Drs. L. Frese, B. Honermeier, and F.A. Kiehn for providing germplasm for research purposes. For information on genetic resources held in collections worldwide, we are extremely grateful to Drs. Laura Marek (U.S.), Hervé Serieys (France), Helmut Knuepffer and Andreas Börner (Germany), Gitte Kjeldsen Bjørn (Denmark), Jovanka Atlagic (Serbia and Montenegro), and Dallas Kessler (Canada).



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The Authors Stanley J. Kays is a professor in the Horticulture Department at the University of Georgia. He received his B.S. degree in horticulture from Oklahoma State University and his M.S. and Ph.D. degrees from Michigan State University. This was followed by postdoctoral research in the Biology Department at Texas A&M University and the School of Plant Biology at the University College of North Wales, Bangor, U.K., and sabbatical research in applied biology at Cambridge University, Cambridge, England. He has held a teaching/research position at the University of Georgia for most of the past 30 years, during which time he has received a number of research awards and published ~180 research papers, predominantly on the physiology and chemistry, postharvest biology, and flavor chemistry of food crops. He has published three books, including Postharvest Biology, a leading reference text on the subject. His current research focus is on rice flavor chemistry and phytoremediation of indoor air.



Stephen F. Nottingham is a research entomologist and science writer based in the U.K. His interests include vegetable crop production, plant protection, insect behavior, chemical ecology, and plant genetic modification. At Cambridge University, England, his Ph.D. thesis was on the host plant-finding behavior of phytophagous Diptera. Subsequent research has been conducted within the aphid biology group at Imperial College, London, on aphid behavior and its modification by volatile chemicals, and at the University of Georgia on sweet potato weevil. Dr. Nottingham has published around 25 research papers and several books, including Eat Your Genes: How Genetically Modified Food Is Entering Our Diet and the Internet-accessible Beetroot. In addition to books, he also writes reports and articles on agriculture and the environment for the European Service Network and other organizations.



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An 1 Introduction: Underutilized Resource The Jerusalem artichoke or topinambour (Helianthus tuberosus L.) is not only a fascinating species, but also one with an exceptionally colorful history. Over the past 300 years, interest in the crop has vacillated widely. During times of crop failure and food shortage (e.g., potato famine, during and after World War II) or high petroleum prices, a new round of interest in the crop’s potential often occurs, all too frequently with only a limited understanding of the extensive body of literature already available. More recently, renewed interest has been spurred by its potential as a feedstock for the synthesis of a diverse cross section of new products, an awareness of its significant health benefits when included in human and animal diets, and the possibility of utilizing it for the production of biofuels. Jerusalem artichoke, which originated in the north central part of the U.S., is a perennial that is grown as an annual. It is a temperate zone crop with an approximate production range between 40 and 55° N latitude and presumably a similar range in the southern hemisphere. Even within this relatively narrow range, cultivar and production requirements differ markedly as one progresses from north to south. Length of the growing season is critical; generally the longer the season, the greater the yield. It does not, however, do well in the tropics, especially in the humid lowlands, even though the growing season is substantially longer than in temperate regions. Unlike some subterranean crops (e.g., sweetpotato), the tubers mature, and the timing of maturity can be critical depending upon the intended use. As a species, Jerusalem artichoke is highly competitive, quickly shading the soil surface and creating a zone of captured resources, thereby repressing the growth of most other species. The plant’s prolific growth is reflected in its efficient calorie production (Table 1.1), which compares well with most major crops. Unlike most crops that store carbon as starch, a polymer of glucose, in the Jerusalem artichoke carbon is stored as inulin, a fructose polymer. The implications of this have a pronounced influence on the value and utility of the crop. An extremely important attribute derived from inulin is its nutritional contributions, even though the caloric value in humans is low. The evidence for the role of inulin in decreasing blood cholesterol and in enhancing other positive health benefits has been firmly established. The Jerusalem artichoke is adapted to both high and low technology and inputs. Increased inputs (e.g., fertilization, irrigation) increase yield but not always net income. Conversely, while not having to apply fertilizer to Jerusalem artichoke following the previous crop may appear to be cost effective, it often simply represents a false economy, as the crop mines the soil of nutrients that must subsequently be replaced before the next crop is planted. Other positive attributes of the crop include the fact that it is vegetatively propagated, allowing growers to produce their own “seed tubers,” which, unlike hybrids, remain true to form. As a consequence, the purchase of new propagation material each year is not required. Finally, the crop currently has few serious insect or disease pests when grown within its normal geographical zone. As a crop plant, the Jerusalem artichoke has languished behind most traditional crop species. Its production worldwide is not considered sufficient to be monitored by the Food and Agriculture Organization (FAO) in its annual production statistics of agricultural crops. Lack of production in the past is in part due to the fact that uses for the crop could be readily fulfilled by other species. As indicated, however, periodic surges in production have been common. For example, during, and for a period after, the Second World War production of Jerusalem artichoke increased in Europe, 1



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TABLE 1.1 Average Yield in Fresh Weight and Calories for Jerusalem Artichoke and the 10 Leading Crops Calories



Crop



Yield (kg·ha–1)a



(kcal·kg–1)b



(kcal·m–2)



Corn (maize) Jerusalem artichoke Sweetpotato Rice Potato Cassava Soybean Wheat Barley Sorghum Grape



4,472 17,843c 13,493 3,837 16,448 10,763 2,261 2,665 2,472 2,261 8,098



3,490 760d 1,000 3,410 710 990 3,920 3,330 3,270 3,420 390



1,561 1,356 1,349 1,308 1,168 1,066 886 887 808 773 316



a



Source: FAO, FAO Yearbook Production, Vol. 57, 2003, Statistics Series 177, Rome, 2004. b Source: Leung, W.W. et al., Food Composition Table for Use in East Asia. I. Proximate Composition Mineral and Vitamin Contents of East Asian Foods, FAO, Rome, 1972. c Based on one third of the mean for yields reported in Table 10.10. d Source: Haytowitz, D.B. and Matthews, R.H., USDA Agriculture Handbook 8-11: Composition of Foods — Vegetables and Vegetable Products, USDA, Washington, DC, 1984.



especially in France and Germany, due to a scarcity of potatoes (Hennig, 2000; Martin, 1963). In France, 99,176 hectares of Jerusalem artichoke were grown in 1905, 131,000 in 1925, and 164,000 in 1956; this declined to 147,000 hectares in 1960 and to only 2,200 hectares by 1987 (Le Cochec, 1988; Shoemaker, 1927). In the U.S., production of Jerusalem artichoke increased during the 1930s, as the crop was promoted as a feedstock for bioethanol. However, markets for this commodity were not sufficiently in place at that time and production declined, with the result that growers remained wary of Jerusalem artichoke for years to come (Amato, 1993). Today, little is grown in the U.S. In U.S. Department of Agriculture (USDA) production statistics, Jerusalem artichoke is grouped with alfalfa sprouts, cardoons, celeriac, jicama, salsify, radicchio, and tomatillos. Small amounts have been grown in recent years, but in 2003 domestic production of this crop grouping was effectively zero, with 450,000 cwt imported (USDA, 2006). The degree of genetic manipulation of the crop is far from adequate. Existing Jerusalem artichoke cultivars fall somewhere between wild types and conventional field crops (e.g., rice, corn, soybean) in their level of genetic development. This is due to two primary reasons: (1) Investment in breeding has been virtually nonexistent compared to the major field crops, and when breeding programs are present, they are generally operative for only very short periods. (2) The reproductive biology of the crop is much more complex than that for most seed-bearing species. This latter factor greatly increases the difficulty of developing highly productive clones. Existing cultivars remain to a significant extent dominated by genes essential in the wild, some of which are detrimental in a field crop. For example, the initial storage of carbon in the stems is followed by the onset of flowering and senescence and finally recycling the carbon into the reproductive organs



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(tubers). All of these developmental stages are strongly modulated by photoperiod, which makes not only understanding what wild traits need to be circumvented but also doing so a significant undertaking. When the photoperiodic control over flowering is broken, tuberization remains strongly modulated by short days. Developing Jerusalem artichoke into a highly productive crop is therefore a formidable challenge. Inulin is the crop’s primary attribute, but its potential is also overshadowed by advances in molecular biology. The genes required for inulin synthesis have been introduced into existing crops (e.g., sugar beet) for which the entire agricultural package (breeding production harvest processing) is currently operative. There is a large and growing body of literature on Jerusalem artichoke, which this present volume summarizes. Fermeren (1932) listed 400 published titles concerning Jerusalem artichoke, while Pätzold (1957) referenced around 1300 publications (Rudorf, 1958). Today, many thousands of publications relate to Jerusalem artichoke, in part because of its role as a model species in the study of plant physiology and biochemistry, in areas such as photoperiodism, cytochrome P450 enzymes, mitochondrial oxidation, carbohydrate fermentation, and micropropagation. Therefore, the species has a scientific value above and beyond its importance as a minor crop. The following paragraphs briefly critique the general information contained in the subsequent chapters. Jersualem artichoke is native to North America, and Native Americans were the first to cultivate it — many years before the arrival of European explorers. The plant’s two most frequently used common names, ‘Jerusalem artichoke’ and ‘topinambour,’ arose shortly after the crop’s introduction into Europe in 1607; both are botanically inappropriate. H. tuberosus neither is related to the artichoke (Cynara scolymus L.) nor has any connection with the town of Jerusalem; the latter derives from the Topinamboux, a South American tribe whose members first visited France in 1613 (Salaman, 1940). Sunchoke has been proposed as a more appropriate common name, but it has not been widely adopted. The nomenclature, origin, and history of H. tuberosus are the subject of Chapter 2. The genus Helianthus (sunflowers), in the family Asteraceae, has around 50 species. The most important species in commercial terms is the cultivated sunflower (Helianthus annuus L.), grown mainly for its oilseed. In contrast, H. tuberosus is distinguished by its large tubers, which have been selected for their food value. No other species of Helianthus is cultivated to a significant extent, although several have value as ornamentals. The classification, identification, and distribution of the genus Helianthus are dealt with in Chapter 3. A number of hybrids naturally form between Helianthus species, including H. tuberosus, within overlapping North American ranges, while further hybrids have been produced as part of plant breeding programs. Both above- and belowground parts of Jerusalem artichoke are utilizable for various applications, for instance, the tops for biomass and animal feed and the tubers as a feedstock for food and nonfood chemical production. All plant parts can potentially be improved to enhance their commercial value. A great deal of morphological variation has been noted in Jerusalem artichoke, despite it being a crop that has undergone relatively little systematic selection, suggesting that genetic improvement is possible. Tubers, for instance, vary in color, shape, size, and surface topography. Plant anatomy and morphological differences between clones and cultivars are described in Chapter 4. Inulin is the storage carbohydrate of Jerusalem artichoke, whereas starch is the storage carbohydrate in the majority of plants. Only a small number of plants accumulate inulin in amounts sufficient for cost-effective extraction, with chicory (Cichorium intybus L.) and Jerusalem artichoke being the most important inulin-storing species. A survey of the occurrence of inulin in plants is presented in Chapter 5, together with an overview of the plant’s chemical composition. Inulin is primarily stored in the tubers, but temporary storage also occurs in the stems prior to tuber filling. Inulin gives the plant its distinctive properties and its particular value for industry. Plant-derived inulin can be processed and modified to serve as a feedstock for numerous industrial applications, as outlined in this chapter.



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The demand for inulin is growing, particularly within the food industry. Mammalian digestive enzymes do not target inulin, and it passes undigested to the large intestine, where bifidobacteria and other beneficial bacteria selectively ferment it. Inulin is added as a prebiotic ingredient to an ever-increasing range of food products, because it helps in the maintenance of a healthy intestinal microflora. Inulin-containing foods are marketed for their weight-loss benefits, and as a low-calorie sweetener, bulking agent, and fat replacement. Inulin can play an important role in combating the obesity epidemic. Diabetic foods also contain inulin, as its ingestion affects blood sugars to a lesser extent than other carbohydrates. As a dietary fiber, inulin promotes improved bowel function, while a number of additional health claims have been made for inulin-type fructans, relating to improvements in mineral absorption in the intestines, improvements in blood lipid composition, the suppression of disease, and the stimulation of the immune system. Moreover, inulin is increasingly added to animal feed, particularly to compensate for the banning of antibiotic dietary supplements. The value of inulin in human and animal diets is explored in Chapter 6. Declining fossil fuel reserves and the need to alleviate the worst consequences of global climate change have stimulated unprecedented interest in alternative fuels and energy sources, including biofuels. Jerusalem artichoke produces large amounts of biomass, is fast growing, needs relatively few inputs in terms of pesticides, fertilizer, and water, and can be grown on marginal land. It is therefore a potentially useful crop for the production of biofuel, and in particular bioethanol (Chapter 7). New strains of inulinase-producing yeast facilitate the conversion of Jerusalem artichoke biomass into ethanol within a single bioreactor. Jerusalem artichoke tops (fresh or ensiled) also have potential for the production of biogas (methane). Cross-pollinating has been the traditional way of breeding Jerusalem artichoke, to generate clones having considerable genetic diversity for subsequent selection. The aim of plant breeders has been primarily to enhance tuber production and inulin content. New techniques like genetic modification can readily be applied to Jerusalem artichoke, as transgenic lines of the closely related cultivated sunflower have already been produced. Raw material for plant breeding programs is obtainable from several important germplasm collections in North America and Europe. A survey of genetic resources for this crop is presented in Chapter 8, along with a discussion of selection criteria and breeding techniques. The chapter concludes with an extensive alphabetical directory of Jerusalem artichoke clones and cultivars. Jerusalem artichoke is usually propagated vegetatively, from tubers or tuber pieces (Chapter 9). Reproduction by seed, although of no consequence in commercial production, is a means of dispersal for wild populations and is vital when crossing in plant breeding programs. Propagation is also possible from rhizomes, slips, and cuttings. Jerusalem artichoke is amenable to propagation by tissue culture, being a model species used in pioneering micropropagation studies. Pollination is predominantly via bees in the field, but can be achieved by hand in greenhouses. Developmental biology, resource allocation, and yield of Jerusalem artichoke form the basis of Chapter 10. Resource allocation in cultivated Jerusalem artichoke differs from that of wild populations, with cultivated clones allocating fewer resources to seeds (sexual reproduction) and more to the tubers (asexual reproduction). The developmental biology of the species is relatively complex when contrasted with most seed-propagated field crops, and as a consequence, understanding the biological and environmental factors modulating growth and development is essential for maximizing productivity. Growth and development are strongly modulated by photoperiod, and while day-neutral cultivars for flowering have been selected, tuberization appears to remain under short-day influence. Photoperiodic control influences what cultivars can be successfully grown in various geographical locations and various aspects of their production. The development of different plant parts is described, with respect to environmental factors, and resource partitioning within plants is discussed with respect to yield. A range of environmental and production factors are noted that can affect yield. Jerusalem artichoke has relatively few pest and disease problems in the field. The main production losses, which are usually modest, arise due to bacterial and fungal pathogens late in the



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season and during storage. Recorded pest and disease organisms known to affect Jerusalem artichoke are described in Chapter 11, along with insects that may play a role in pollination. A range of agronomic practices increase yield, including choice of planting date, weed control, fertilization, irrigation, and efficient planting and harvesting procedures (Chapter 12). Weeds are rarely a problem in Jerusalem artichoke, because the crop outcompetes most other plant species, although herbicides may be beneficial during crop establishment. Jerusalem artichoke can be a troublesome weed in rotations, and herbicides may be needed to eradicate volunteer plants in following crops. Fertilizers can increase productivity, although excessive nitrogen fertilization may boost top growth to the detriment of tuber yields. Irrigation increases yield in hot, arid regions, although the crop is relatively drought and salt tolerant. Jerusalem artichoke tubers can be left in situ and harvested as needed, or lifted and stored in common stores (e.g., cellars and pits) or under refrigeration. Cold storage is effective, although refrigeration adds to production costs. Tubers can be stored up to 12 months under optimal conditions. However, carbohydrate composition alters significantly during storage, with the depolymerizing of inulin having implications for various industrial applications. Storage options are discussed in Chapter 13. There is increasing demand for inulin and bioethanol, two products that can be derived from Jerusalem artichoke. Inulin is mainly derived from chicory, which is increasingly grown as an alternative to sugar beet due to a decreasing demand for sucrose. Bioethanol is mainly produced from sugar cane or corn (maize). Jerusalem artichoke must therefore demonstrate economic advantages over these alternative crops. Potential advantages include profitable by-products and cheaper inputs. Jerusalem artichoke has relatively low input requirements and can be cultivated on marginal land, making it a promising additional feedstock for inulin, biomass, and biofuels. Corn, in contrast, has relatively high inputs, and bioethanol production from corn diverts land and grain from food production. Production costs for Jerusalem artichoke vary with region, land price, processing plant size, and other factors. The economics of producing and marketing Jerusalem artichoke are the subject of the final chapter. Jerusalem artichoke therefore has potential as a multipurpose crop, with the value of its byproducts a key to its future commercial exploitation. A listing of patents that relate to Jerusalem artichoke (Appendix), particularly utilizing plant-derived inulin, illustrates an increasing interest in the crop. The future of the Jerusalem artichoke is far from clear, however, when plotting its course from this point in time; the attributes of the species, especially those that cannot be readily and more efficiently met by existing crops, need to be closely assessed. Jerusalem artichoke has long been known to be highly efficient and competitive. Perhaps rather than removing or repressing the genes that make the species so effective in the wild, the crop could be developed for low inputs and culture in marginal soils, on land that will not displace existing crops. For instance, rather than selecting for the absence of stem storage and early tuberization, the crop could be grown as a perennial, as in the wild, for harvesting just the aerial portion of the plant, before extensive recycling of carbon from the stems into the tubers. In the interim, the Jerusalem artichoke remains an underexploited natural resource awaiting the input of resources and expertise needed for the utilization of its unique attributes.



REFERENCES Amato, J.A., The Great Jerusalem Artichoke Circus: The Buying and Selling of the Rural American Dream, University of Minnesota Press, Minneapolis, 1993. FAO, FAO Yearbook Production, Vol. 57, 2003, Statistics Series 177, Rome, 2004. Fermeren, N.O., [List of publications on Jerusalem artichoke (Helianthus tuberosus L.)], Inst. Plant Industry, Leningrad Library, Bibl. Contr., No. 1, 1932.



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Haytowitz, D.B. and Matthews, R.H., USDA Agriculture Handbook 8-11: Composition of Foods — Vegetables and Vegetable Products, USDA, Washington, DC, 1984. Hennig, J.-L., Le Topinambour & autres Merveilles, Zulma, Cadeilhan, France, 2000. Le Cochec, F., Les clones de Topinambour (Helianthus tuberosus L.), caracteres et methode d’amelioration, in Topinambour (Jerusalem Artichoke), Gosse, G. and Grassi, G., Eds., European Commission Report 13405, Commission of the European Communities (CEC), Luxembourg, 1988, pp. 23–25. Leung, W.W., Butrum, R.R., and Chang, F.H., Food Composition Table for Use in East Asia. I. Proximate Composition Mineral and Vitamin Contents of East Asian Foods, FAO, Rome, 1972. Martin, B., Die Namengebung einiger aus Amerika eingeführter Kulturpflanzen den deutschen Mundarten (kartoffel, topinambur, mais, tomato), Beiträge zur Deutschen Philogie, 25, 1–153, 1963. Pätzold, C., Die Topinambur als landswirtschaftliche Kulturpflanze, Herausgegeben vom Bundesministerium für Ernährung, Landswirtschaft und Forsten in Zusammenarbeit mit dem Land- und Hauswirtschaftlichen Auswertungsund Informationsdienst e.V. (AID), Braunschweig-Völkenrodee, Germany, 1957. Rudorf, W., Topinambur, Helianthus tuberosus L., Handbuch der Pflanzenzüchtung, 3, 327–341, 1958. Salaman, R.N., Why “Jerusalem” artichoke? J. Royal Hort. Soc., LXVI, 338–348, 376–383, 1940. Shoemaker, D.N., The Jerusalem artichoke as a crop plant, USDA Technical Bulletin 33, U.S. Dept. of Agriculture, Washington, DC, 1927. USDA, Crop Production, http://www.usda.gov/nass/pubs/agstats/, 2006.



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Origin, and 2 Nomenclature, History 2.1 NOMENCLATURE FOR Helianthus tuberosus L. A diverse assortment of Latin and common names have been ascribed to Helianthus tuberosus since its introduction into Europe, making its history and outward dispersal from the New World difficult to trace. Linné assigned the current Latin binomial (H. tuberosus L.) for the species in 1753. Today his system of classification is universally accepted, though it was not uniformly welcomed at that time. This sentiment is evident in the following comment by Brookes, published in 1763: I hope therefore Students will excuƒe me for not having adopted either the ƒyƒtems of Tournefort, or Linnæus, in contradiction to nature and experience; my deƒign being not to asuƒe the ƒpeculative, but to direct the induƒtrious. Their attempts to reduce the names of plants into a ƒyƒtem, has rendered the ƒtudy more difficult and more ƒubject to error, than it would have been if the Student had only uƒed his ƒight for the diƒtinguiƒhing of plants, and his memory for regiƒtring them.



It is therefore not surprising that there have been a wide assortment of names ascribed to the species, reflecting varying levels of accuracy or appropriateness (Table 2.1). Or as Redcliffe Salaman (1940) aptly states, H. tuberosus and Helianthus annuus during “their 300 years sojourn in Europe have acquired a bewildering number of aliases.” In fact, the two most widely used common names, Jerusalem artichoke and topinambou, are neither accurate nor appropriate. Salaman (1940) presents a detailed account of their possible derivation. Starting with Jerusalem artichoke, analysis of the literature underscores the fact that the species is not an artichoke, nor does it have anything to do with Jerusalem. The artichoke portion of the common name appears to have been added in that the cooked tubers are somewhat reminiscent of the taste and texture of the fleshy receptacle of the globe artichoke (Cynara scolymus L.). Samuel de Champlain, the first European to describe the plant in the New World (Massachusetts in 1605), compared its flavor to that of the artichoke in a description of his visit to the homes of the natives with Seigneur De Monts, the leader of the expedition (Bourne, 1906). They passed through fields of Indian corn and “saw an abundance of Brazilian Beans, many edible Squashes of various sizes, Tobacco and roots which they cultivate, the latter having the taste of Artichokes” (Champlain, - meaning 1613). The name artichoke is believed to have been derived from the Arabic Al-kharshuf, rough skinned. By transition through Spanish-Arabic (Al-kharshofa) and old Spanish (Alcarchofa), the name was passed to old Italy as Alcarcioffo, or in modern Italian, Articiocco, which led to artichoke in English, which was first used in the English language in 1531 (Simpson and Weiner, 1989). The use of Jerusalem as part of the common name for H. tuberosus has two plausible origins. The first is that it is a corruption of the Italian name girasole articiocco, or sunflower artichoke, a theory put forward by J.E. Smith in 1807. Difficulty in pronouncing girasole by the English led to Jerusalem’s etymological derivation. This interpretation, however, is predicated upon the existence of girasole in the 17th century, a fact challenged by Gibbs (1918) and Salaman (1940). The sunflower (H. annuus) arrived in Europe during the mid-16th century; for instance, Leonhard Fuchs named and illustrated it between 1544 and 1555 (Meyer et al., 1999). Meanwhile, the girasol appears to



7



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TABLE 2.1 Names used for H. tuberosus L. Since the 1600s Name Aardpeer Adenes Canadenses American artichoke Artichaut de Canada Artichaut de Jérusalem Artichaut de Terre Artichaut du Canada Artichaut of terre Artichaut Souterrain Artichoke Artichoke apples of Ter-Neusen Artichoke d’Inde Artichoke of Jerusalem Artichokes of Jerusalem Artichoke under the ground Artichokes van Ter Neusen Articiochen onder d’aerde Artischockappeln Artischockappeln van Ter Neusen Artischocken unter Erden Artischokenappel van Ter Neuzen Artischoki sub terrâ Aster Peruanos tuberosus Aster Peruanus Aster Peruanus tuberosus Batata carvalha Batatas Canadensis Batatas Candense Batatas von Canada Battatas de Canada Bulwa Canada Canada et Artischoki sub terrâ Canada potato Canadas Canadiennes Cartoffel Chiquebi Choke Chrysanthemon latifolium Chrysanthemum Canadense Chrysanthemum Canadense arumosum Chrysanthemum Canadense tuberosum edule Chrysanthemum è Canada Chrysanthemum latifolium brasilianum Chrysanthemum perenne majus solis integris, americanum tuberosum



Reference Becker-Dillingen, 1928; Driever et al., 1948 Lauremberg, 1632 Sprague et al., 1935 Géardi, 1854 Lecoq, 1862; Becker-Dillingen, 1928; Pinckert, 1961 Lecoq, 1862 Lecoq, 1862; Becker-Dillingen, 1928 Géardi, 1854 Baillarge, 1942 Dodoens et al., 1618 Anon., 1658 A variation of Jerusalem artichoke Küppers, 1956 Translation of Dodoens’s Articiochen onder d’aerde Dodoens, 1618 Dodoens, 1618 Lauremberg, 1632 Lauremberg, 1632 Lauremberg, 1632 Küppers, 1956 Vallot, 1665 Colonna, 1616 Willughby and Ray, 1686 Colonna, 1616 Becker-Dillingen, 1928 Beverly, 1722 Küppers, 1956 Dodoens, 1618 Parkinson, 1629 Becker-Dillingen, 1928 Baillarge, 1942 Bauhin, 1671 Baillarge, 1942 Sagard-Theodat, 1836 Rhagor, 1639 Hegi, 1906/1931 Shoemaker, 1927 Bauhin, 1671 Dodoens, 1618; Moretus, 1644 Schuyl, 1672 Dodoens, 1618 Bauhin, 1671 Linnaeus, 1737; Bauhin, 1671 Morison, 1680; Linnaeus, 1737



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TABLE 2.1 (CONTINUED) Names used for H. tuberosus L. Since the 1600s Name Cicˇ oka Cnosselen Compire Corona solis parvo flore, tuberosa Cotufa Csicsóka Earth-puff Erd-apfel Erdapfel Erdartischocke Erdartischoke Erdbirne Erdmandl Erdschocke Ewigkeitskartoffel Flos Solis Canadensis Flos Solis Farnenanious Flos Solis Farnesianus Flos Solis glandulosus Flos Solis Pyramidalis Flos Solis tuberosa radice Flos Solis tuberosus Frenches Battatas Girasole Girasole del Canada Griasole [Girasole?] de Canada Grond-peer Ground berry Ground pear Grundbirne Gyrasol do Brasil tuberoso Hartichokes Helenii tuberosum Helenium canadense Helianthemum indicum tuberosum Helianthemum tuberosum Helianthi Helianthum tuberosum esculentum Helianthus radice tuberosa Helianthus tomentosus Helianthus tuberosus Helianthus tuberosus var. subcanescens Heliotropium Indicum tuberosum Heliotropum Indicum tuberosum Herba solis tuberosa Herba solis tuberosa radice Hierusalem artichoke Honderthoofden



Reference Becker-Dillingen, 1928 Lauremberg, 1632 Lecoq, 1862; Baillarge, 1942 Boerhaave, 1720; Linnaeus, 1737 Becker-Dillingen, 1928; Escalante, 1946 I’So, 1955 Angyalffy, 1824; Hegi, 1906/1931 Flemish Anon., 1731; Rodiczky, 1883; Becker-Dillingen, 1928 German Anon., 1731; Angyalffy, 1824; Scheerer, 1947 Angyalffy, 1824; Rodiczky, 1883; Löbe, 1850 Küppers, 1949 Küppers, 1949 Küppers, 1949; Prehl, 1953 Dodoens et al., 1618 Salmon, 1710 Colonna, 1616 Vallot, 1665 Gerarde, 1597 Linnaeus, 1737 Aldinus, 1625 Parkinson, 1640 Hegi, 1906/1931 Becker-Dillingen, 1928; Krafft, 1897 Targioni-Tozzetti, 1809 Baillarge, 1942 Prain, 1923 Soviet News, 1947 Scheerer, 1947 Becker-Dillingen, 1928 Anon., 1649 Ammann, 1676 Brookes, 1763; Bauhin, 1671 Brookes, 1763 Thellung, 1913 Diderot, 1765 Linnaeus, 1737 Michaux, 1801 Linnaeus, 1753 Gray, 1869 Küppers, 1956 Salmon, 1710 Moretus, 1644 Dodoens, 1618 Parkinson, 1640 Lauremberg, 1632



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TABLE 2.1 (CONTINUED) Names used for H. tuberosus L. Since the 1600s Name Hundred-heads Hxiben Jerusalem artichoke Jerusalemartischoke Jirasol tuberoso Jordaeble Jordäple Jordärtskocka Jordskokken Judenbirne Judenerdapfel Judenkartoffel Kaischuc penauk Kaishcucpenauk Knauste Knobs Knollensonnenblume Knollenspargel Knollige Sonnenblume Knollige Sonnenrosen Knousten Laska répa Orasqueinta Papezˇ ica Papinabò Pariser Edelerdartischoke Pataca (Argentinean) Patache (Sicilian) Patata Patata americana Patata del Canada Patata di Canada Pero di terra Peruanum Solis florem ex Indiis tuberosum habuimus Peruanus Solis flos ex Indiis tuberosus Pferdekartoffel Poire de terre Poire de Terre Pomme de terre Pommes de Canada Potato of Canada Potato plant Rehkartoffel Roßbirne Roßgrundbirne Roßkartoffel Root-artichoke Russische Bodenbirne



Reference Dodoens, 1618 Gibault, 1912; Baillarge, 1942; Küppers, 1952b Common English name for the species Germershausen, 1796 Becker-Dillingen, 1928 Becker-Dillingen, 1928 Becker-Dillingen, 1928 Becker-Dillingen, 1928 Becker-Dillingen, 1928 Rodiczky, 1883 Rodiczky, 1883 Scheerer, 1947 Trumbull and Gray, 1877 Küppers, 1956 Lauremberg, 1632 Dodoens, 1618 Scheerer, 1947 Küppers, 1949 Angyalffy, 1824; Linnaeus, 1797 Schwerz, 1843 Lauremberg, 1632 Becker-Dillingen, 1928 Sagard-Theodat, 1836 Becker-Dillingen, 1928 A corruption of topinambur or topinambour Wettstein, 1938 Becker-Dillingen, 1928 Becker-Dillingen, 1928 Catalina, 1949 Küppers, 1956; Targioni-Tozzetti, 1809 Targioni-Tozzetti, 1809 Hegi, 1906/1931 Becker-Dillingen, 1928 Hernandez, 1648 Hernandez, 1651 Becker-Dillingen, 1928; Scheerer, 1947 Géardi, 1854 Lecoq, 1862; Baillarge, 1942 Initially used in France but subsequently was substituted for Solanum tuberosum Sagard-Theodat, 1836; Baillarge, 1942 Parkinson, 1629 Küppers, 1949 Scheerer, 1947 Hegi, 1906/1931 Rodiczky, 1883 Hegi, 1906/1931



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TABLE 2.1 (CONTINUED) Names used for H. tuberosus L. Since the 1600s Name Salsifis Schnapskartoffel Semljannaja gruscha Sol altissimus radice tuberosa esculenta Soleil vivace Soleil vivace Solis Flore tuberosus Solis flos Farnesianus Solis herba Canadensis Sonnenrose Sow bread Stangenerdapfel Süßkartoffel Sun-root Sunchoke Sunflower artichoke Sunroot Tapinabò Tartouffe Tartoufle Tartüffeln Tartuffi bianchi Tartuffo di Canna Tartufo bianco Tartufo di Canna Tartufoli Taupinambours Taupine Terre à touffe Tertifle Tertifle Tiramirambo Topinabò Topinamba Topinambou Topinambour Topinambous Topinambur Topinambur Topinambura Topinambury Topine Tropenkartoffel Trtur Truffles du Canada Tuberous rooted sunflower Tubers Tüffeln



Reference Caspari, 1948 Prehl, 1953 Fermeren, 1932; Becker-Dillingen, 1928 Linnaeus, 1737 Lecoq, 1862; Baillarge, 1942 Géardi, 1854 Aldinus, 1625 Colonna, 1616 Dodoens, 1618 Nefflen, 1848 Angyalffy, 1824 Rodiczky, 1883; Pinckert, 1861 Küppers, 1949 Robinson, 1920 Name given to a H. annuus H H. tuberosus hybrid Shoemaker, 1927 A corruption of topinambur or topinambour Géardi, 1854 Baillarge, 1942 Prehl, 1953 Küppers, 1956 Hegi, 1906/1931 Anon., 1741 Targioni-Tozzetti, 1809 Becker-Dillingen, 1928 Schlechtendal, 1858 Baillarge, 1942 Géardi, 1854 Géardi, 1854 Lecoq, 1862 Ravault, 1952 A corruption of topinambur or topinambour Becker-Dillingen, 1928 Petersons, 1954 Driever et al., 1948; Targioni-Tozzetti, 1809; Becker-Dillingen, 1928; Lecoq, 1862 Anon., 1658 Becker-Dillingen, 1928 Griesbeck, 1943; Schwerz, 1843 Fermeren, 1932 Becker-Dillingen, 1928 Schmitz-Winnenthal, 1951; Anon., 1952 Küppers, 1952a Becker-Dillingen, 1928 Baillarge, 1942 Becker-Dillingen, 1928 Dodoens, 1618 Prehl, 1953



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TABLE 2.1 (CONTINUED) Names used for H. tuberosus L. Since the 1600s Name Tupinabò Underschocken Unter Erdschen Unterartischoke Weißwurzel Wildkartoffel Zidovski neb ruski brambory Zuckerkartoffel



Reference A corruption of topinambur or topinambour Lauremberg, 1632 Lauremberg, 1632 Scheerer, 1947; Hegi, 1906/1931 Scheerer, 1947; Hegi, 1906/1931; Küppers, 1949 Prehl, 1953 Becker-Dillingen, 1928 Prehl, 1953



Source: Compiled using Pätzold, C., Die Topinambur als Landwirtschaftliche Kulturpflanze, Institut für Pflanzenbau und Saatguterzegung der Forschungsanstalt für Landwirtschaft, Braunschweig-Völkenrode, Germany, 1957 and additional material.



have been used in reference to it toward the turn of the century. For example, in 1598 Phillip Sidney used “Girasol” (Sidney, 1598). With gazing eyes he looks, short sighs unsettled feet He stood, but turned as Girasol to sun His fancies slite did her in halfe way meet His soul did fly as she was seen to run.



alluding to the heliotropic response of what one would construe was the sunflower; i.e., the flower heads turn with the movement of the sun from east to west during the day, returning to their original position during the night (Lang and Begg, 1979; Schaffner, 1900). It is apparent, at least, that the term girasol was in use, predating the spread of H. tuberosus on the continent. Salaman (1940) argues, based upon Italian dictionaries between 1598 and 1688, that girasole, while present, is not used for H. annuus. Not until 1729 in Vocabolario degli Academici della Crusca is girasole used to refer specifically to the sunflower, though as early as 1611 in John Florio’s Queen Anna’s New World of Words, it is used for a plant that turns with the sun. Whether its use is in reference to H. annuus or one of several other heliotropic species is not clear, but definitely cannot be ruled out. Salaman concludes that “there appears to be no evidence, whether sought among specialist botanical sources or from the common language of the day, that the word Girasole was used during the period under discussion in Italy or elsewhere either for our Sunflower, H. annuus, or for the Jerusalem Artichoke, H. tuberosus.” The alternative proposal for the origin of Jerusalem in the common name for H. tuberosus is that it is a corruption of a location where the crop was grown in the early 1600s. Petrus Hondius, a pastor in the Netherlands, grew and distributed the tubers from Ter Neusen, resulting in the crop being considered a product of Ter Neusen. The 1618 edition of Dodoens’s Cruydt-Boeck mentions Artischokappeln van Ter Neusen, as did Lauremberg’s Apparatus Planterius Primus in 1632. David Prain, by way of Salaman (1940), proposed that the crop was imported to England as Artichokes van Ter Neusen, which readily became corrupted to Artichokes of Jerusalem and subsequently to Jerusalem artichokes. The second common name, which has no apparent relationship to the species, is topinambur. Topinambur (or variations thereof) is currently used in Bulgarian, Czech, Dutch, English, Estonian, French, German, Italian, Lettish, Lithuanian, Polish, Portuguese, Romanian, Russian, Slovak, Spanish, and Ukrainian (Table 2.2). The story of how H. tuberosus came to be called topinambur is equally intriguing. Between 1609 and 1617, H. tuberosus was introduced into France, where it



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TABLE 2.2 Current Common Names for Helianthus tuberosus L. in Various Languages Name Aardpeer Aardaartisjok Aguaturma Alcachofa de Jerusalém Artichaut de Jérusalem Articokks Beyaz yer elmasl Brahmokha Bulwa Carciofo di Gerusalemme Carciofo di terra Castaña de tierra Cotufa Csicsóka Elianto tuberoso Erd-apfel Erdartischocke Erdbirne Girassol batateiro Girassol tuberoso Grusha zemljanaja Gui zi jiang Hathipich Hatichuk Jerusalem artichoke Jerusalem artichoke Jerusalem artisjok Jordärtskocka Jordskocka Jordskok Jordskokk Ju yu Kartofel loshadnnyi Kikumo [kiku imo] Knolartisjok Knollensonnenblume Knollsolsikke Kollokasi Krkuska ˇ Lashka repa Maa-artisokka Maapirn March-ysgall Mollë Mugul-artishokk Mugulpäevalill Mukula-artisokka Näiteks maapirn



Language Dutch Dutch Spanish Spanish French Maltese Turkish Bengali Polish Italian Italian Spanish Spanish (Philippines) Hungarian Italian Flemish German German Portuguese Portuguese Russian Chinese-Wú Punjabi Hindi Assamese English Afrikaans Swedish Swedish Danish Norwegian Chinese-Mandarin Russian Japanese Afrikaans German Norwegian Greek Macedonian Slovene Finnish Estonian Welsh Albanian Estonian Estonian Finnish Estonian



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TABLE 2.2 (CONTINUED) Current Common Names for Helianthus tuberosus L. in Various Languages Name Nyamara Padsolnechnik klubnenosnyi Pataca Preeria-auringonkukka Qui zi jiang Slanechnik clubneneosny / Slonecznik bulwiasty Sunchoke Tavuk gökü Tertufa Topìambur Topinambas Topinambo Topinambo Topinamboer Topinambour Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur Topinambur elianto Topinambur hlíznaty´ Topinamburs Topinembur Ttung dahn ji Ttung ttan ji Tupinambo Woodland sunflower Yang jiang Yang jinag Yerelmasi Zi bei tian kui



Language Catalan Russian Spanish Finnish Chinese-Cantonese Bylerussian Polish English Turkish Arabic Ukrainian Lithuanian Portuguese Spanish Dutch French Bulgarian Czech English Estonian Germany Italian Polish Romanian Serbo-Croatian Slovene Italian Czech Lettish Slovak Korean Korean Spanish English Chinese-Cantonese Chinese-Wú Turkish Chinese-Cantonese



Source: Adapted from Kays, S.J. and Silva Dias, J.C., Cultivated Vegetables of the World: Latin Binomial, Common Name in 15 Languages, Edible Part, and Method of Preparation, Exon Press, Athens, GA, 1996, with additional names. With permission.



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acquired the name topinambour. The name appears to have been derived from the mistaken impression in the early 1600s that the crop was native to and introduced from South America (e.g., Linnaeus in the Species Plantarum (1753) described its origin as Brazilian, though in his earlier Hortus Cliffortianus (1737) denoted Canada). The Seigneur of Razilly, Claude Delaunay’s expedition, visited Brazil in the early years of the 17th century and returned to Paris in 1613 with six natives from the Isle de S. Luiz de Maranhão. They were members of a tribe of the warlike race of Guaranís, known as the Topinambous. The natives, whose appearance in Paris created considerable excitement among the general populace, were presented to Queen Mary de’ Medici on April 15, 1613. The idea of their presence creating what is now termed a media event is supported by letters from Francois de Malherbe (1862) to the naturalist Nicholas de Pieresc on April 15 and June 23, 1613. To-day [April 15] the Seigneur of Razilly, who in the last few days has returned from the Isle of Maragnan, has shown the Queen six Topinambours whom he has brought from that country. In going through Rouen he dressed them in French style, for according to the custom of their country they go quite naked except for some black rags with which they cover their private parts. The women wear nothing. They dance a kind of swing without holding hands or moving from the place. Their fiddles were a gourd like those which the pilgrims use for drinking, and inside they have some kind of nail or pin.… The Topinamboux will be baptised tomorrow [June 24]: if there is a chance of seeing it without being crushed, I shall do so; if not, I shall get those who were there to report to me. Already a couple of wives have been found for them; I understand they are only waiting for their baptism, to celebrate the marriage and ally France to the Island of Maranan.



It is evident that Razilly’s exotic natives were a great attraction and the center of attention in Paris in early 1613, the timing of which coincided with the marketing of the latest root crop. Streethawkers, trying to sell the strange and rather uncouth-looking newly introduced tubers of H. tuberosus, adopted the term topinambou to draw attention to their exotic offering (Salaman, 1940). The word topinambou subsequently came to mean something gross and absurd. The explanations for the origin of topinambou as a common name and artichoke as part of the common name appear readily acceptable, though the origin of the use of Jerusalem is of greater question. While two plausible explanations for the origin of Jerusalem in the common name are presented, we are left without a definitive choice. The most commonly quoted derivation to this day (i.e., from girasole) now appears to be questionable. Regardless, it is of considerable interest that the common names for the species could have deviated so far from the original Indian names for the plants, such as kaischuc penauk, which Salaman (1940) notes as the native name used in Virginia, derived from one of the Algononquian languages (Austin, personal communication), and translated by Trumbull and Gray (1877) as “sun roots.” The addition and retention of Jerusalem in the common name is illogical at best. Or as Gould so aptly states in The Flamingo’s Smile (1985), “The propagation of error, by endless transfer from textbook to textbook, is a troubling and amusing story in its own right — a source of inherited defect almost more stubborn than inborn errors of genetics.” What should the common name for the crop be? Alternative names that have been proposed range from sun-root (though technically the edible portion is not a root) proposed by Trumbull and Gray in 1877 to sunchoke. In 1918 the Gardener’s Chronicle offered a prize for a new, more appropriate English name for the Jerusalem artichoke (Gibbs, 1918); however, from the continued use of Jerusalem artichoke, it is evident that the winning name was not considered an acceptable improvement.



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2.2 ORIGIN There was initially confusion concerning where the Jerusalem artichoke originated. Linnaeus, in Species Plantarum (1753), indicated a Brazilian origin, though in his earlier Hortus Cliffortianus (1737), he listed H. tuberosus as from Canada. Paxton also indicated the species as first introduced into England in 1617 from Brazil (Hereman, 1868). The impression of a South American origin may in fact have contributed to the acceptance of the common name topinambou adopted from the name of the natives (Topinambous) from the Isle de S. Luiz de Maranhão on the coast of Brazil. The correct center of origin, or at least more nearly correct, keeping in mind that during the 16th and 17th centuries “Canada” represented a much broader area than in modern times, seems to have been relatively widely accepted by European botanists toward the end of the 17th century as evidenced by the names ascribed to the species in the herbals of the day; e.g., “Adenes Canadenses” in Peter Lauremberg’s Apparatus Plantarius Primus (1632); “Canada” and “Artischoki sub terrâ” by Antoine Vallot in Hortus Regis Paris (1665); “Chrysanthemum Canadense Arumosum” in F. Schuyl’s Catalogus Plantarum Horti (1672); and “Helenium Canadense” in Paul Ammann’s Character Plantarum Naturalis (1676). Alphonse DeCandolle in his Géographie Botanique (1855) likewise indicated that the South American origin was in error. Regardless, numerous incorrect listings continued to appear even into the 20th century. For example, Martyn in the 1807 edition of Miller’s Gardener’s and Botanist’s Dictionary states that “they are unquestionably the produce of a hot climate, being natives of Brazil,” Robinson (1871) “a native of Brazil,” and Gray (Torrey and Gray, 1843) “an introduced species, said to have been derived originally from Brazil.” Upon growing a sample of Helianthus doronicoides Lam. received from Dr. Short in Kentucky in 1855, the American botanist Asa Gray found that the original long, slender tubers became shorter and thicker after 2 or 3 years of cultivation. He concluded that H. doronicoides was the parent of H. tuberosus in his Manual of Botany of the Northern United States (Gray and Sullivant, 1856). In Lessons in Botany (1869) and in subsequent editions of the manual until 1883, he reversed his decision and concluded that the wild species was not H. doronicoides. While a North American center of origin is well accepted based upon the distribution of H. tuberosus, it is not certain that the actual center of origin was today’s Canada. Gray in 1883 said that the aborigines who cultivated it must have obtained it from the valleys of the Ohio and Mississippi and their tributaries, where it abounds. The natural distribution of H. tuberosus unfortunately does not provide an adequate clue in that the species has been distributed widely through human activity and escapes often become naturalized. Therefore, it is doubtful that the highest density of the species in North America reflects the actual center of origin. The natural distribution of possible progenitor species whose union resulted in H. tuberosus, assuming neither are extinct nor have been cultivated and thereby distributed by people, would perhaps be more useful (Figure 2.1). Thus, areas of overlap in the natural distributions could point toward a probable area in which the species originated. This scenario requires the distribution of the parent species to not have shifted markedly from the time in which H. tuberosus originated. The question then becomes: from which species did H. tuberosus most likely originate? Helianthus tuberosus is a polyploid with 102 chromosomes. Polyploids are thought to originate through the hybridization between two different species, giving rise to a progeny in which chromosome doubling occurs. For example, hybridization between a species with 34 and one with 68 chromosomes would produce a triploid (51 chromosomes), and with chromosome doubling would yield 102 chromosomes. To test the potential for gene flow between Helianthus species, crosses have been made among a cross section of species and a number of hybrids produced (Rogers et al., 1982). Heiser (1978) proposed that the 68-chromosome parent “almost certainly” has to be one of three species (H. decapetalus L., H. hirsutus Raf., or H. strumosus L.), which are all found within the central and eastern U.S. Of these, H. hirsutus has the greatest morphological resemblance to H. tuberosus. For the 34-chromosome species, H. giganteus L., H. grosseserratus Martens, or less lik