Hundreds of garlic (Allium sativum L.) cultivars are available from seed companies, retailers, and germplasm collections. Increasingly, bulbs intended for planting are purchased from nonlocal sources and the resulting yields can be unpredictable; garlic bulbs resulting from seed stock purchased in other regions often do not display the characteristics such as bulb size, shape, and color that were listed in the catalogs. This is a result of the high degree of variability in clove wrapper color, bulb size, yield, and flavor influenced by growth environment, cultivar, and production year (Waterer and Schmitz, 1994).
Locations differ in soil type, fertility, water availability, growing temperatures, daylength, solar radiation, and management practices. Because garlic is highly adaptive to its growth environment, yields remain consistent or may improve when bulbs are replanted in similar conditions in which they were produced (Waterer and Schmitz, 1994). As a consequence, it is frequently recommended that local garlic be purchased as planting stock or to allow several years of production for adaptation to a new environment (Engeland, 1991).
Previous work has sought to correlate some physical features of garlic with garlic type identification (Engeland, 1991, 1995; Maaß and Klaas, 1995; Volk et al., 2004). Studies that compared appearance with bulb firmness, pH, soluble solids, moisture content, and sugar content determined that many of these traits are independent of bulb chroma and hue angles of the skin color across 14 garlic cultivars (Pardo et al., 2007). Other traits that vary across cultivars when grown under the same environmental conditions include the leaf number before bolting, flowering date, final stem length, flower/topset ratio, and pollen viability (Kamenetsky, 2007).
The continual growth and recent interest in new cuisines as well as health benefits of garlic have brought the diversity of garlic types to the attention of the public. Grocery stores frequently carry white, softneck (nonscape-producing) garlic types that are mostly imported and generally amenable to mechanized production. Alternatively, hardneck (scape-producing) types that come in various shades of purples, magentas, pinks, and whites are available at local vegetable stands and direct marketing programs. However, garlic cultivar identification is challenging as a result of its phenotypic plasticity (Al-Zahim et al., 1997; Ipek et al., 2003).
In 2004, Volk et al. published an assessment of the genetic diversity of 211 garlic cultivars. Garlic types silverskin, artichoke, rocambole, porcelain, purple stripe, marble purple stripe, and Asiatic were genetically differentiated (Volk et al., 2004). Other garlic types such as turban, creole, and glazed purple stripe were underrepresented and thus not clearly differentiated. One cultivar representing each of the 10 garlic types listed here was selected to best capture the genetic diversity available within Allium sativum to identify the range of phenotypic responses observed at diverse growth locations in a 2-year project.
We report on the variation observed in bulb elemental composition and morphological characteristics of the 10 garlic cultivars across the diverse growth locations. We identify stable traits that can serve as useful indicators for garlic type classification on a national scale to increase the standardization of garlic classification terminology.
Al-Zahim, M. , Newbury, H.J. & Ford-Lloyd, B.V. 1997 Classification of genetic variation in garlic (Allium sativum L.) revealed by RAPD HortScience 32 1102 1104
Conci, V.C. , Canavelli, A. , Lunello, P. , DiRienzo, J. , Nome, S.F. , Zumelzu, G. & Italia, R. 2003 Yield losses associated with virus-infected garlic plants during five successive years Plant Dis. 87 1411 1415
Coolong, T.W. , Kopsell, D.A. , Kopsell, D.E. & Randle, W.M. 2004 Nitrogen and sulfur influence nutrient usage and accumulation in onion J. Plant Nutr. 27 1667 1686
Coolong, T.W. & Randle, W.M. 2003 Sulfur and nitrogen availability interact to affect the flavor biosynthetic pathway in onion J. Amer. Soc. Hort. Sci. 128 776 783
Dickerson, G.W. & Wall, M. 1997 Varietal evaluation of garlic in New Mexico New Mexico State University Agricultural Experiment Station Research Report 717
Huchette, O. , Arnault, I. , Auger, J. , Bellamy, C. , Trueman, L. , Thomas, B. , Ochatt, S.J. & Kahane, R. 2007 Genotype, nitrogen fertility and sulphur availability interact to affect flavour in garlic (Allium sativum L.) J. Hort. Sci. Biotechnol. 82 79 88
Ipek, M. , Ipek, A. , Senalik, D. & Simon, P.W. 2007 Characterization of an unusual cytoplasmic chimera detected in bolting garlic clones J. Amer. Soc. Hort. Sci. 132 664 669
Ipek, M. , Ipek, A. & Simon, P.W. 2003 Comparison of AFLPs, RAPD markers, and isozymes for diversity assessment of garlic and detection of putative duplicates in germplasm collections J. Amer. Soc. Hort. Sci. 128 246 252
IPGRI, ECP/GR, AVRDC 2001 Descriptors for Allium (Allium spp.) International Plant Genetic Resources Institute,Rome,Italy; European Cooperative Programme for Crop Genetic Resources Networks (ECP/GR), Asian Vegetable Research and Development Center Taiwan
Jenderek, M.M. & Hannan, R.M. 2004 Variation in reproductive characteristics and seed production in the USDA garlic germplasm collection HortScience 39 485 488
Kamenetsky, R. , Shafir, I.L. , Khassanov, F. , Kik, C. , van Heusden, A.W. , Vrielink-van Ginkel, M. , Burger-Meijer, K. , Auger, J. , Arnault, I. & Rabinowitch, H.D. 2005 Diversity in fertility potential and organo-sulphur compounds among garlics from Central Asia Biodivers. Conserv. 14 281 295
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Kamenetsky, R. Shafir, I.L. Khassanov, F. Kik, C. van Heusden, A.W. Vrielink-van Ginkel, M. Burger-Meijer, K. Auger, J. Arnault, I. Rabinowitch, H.D. 2005 Diversity in fertility potential and organo-sulphur compounds among garlics from Central AsiaBiodivers. Conserv. 14 281 295
Kamenetsky, R. , Shafir, I.L. , Zemah, H. , Barzilay, A. & Rabinowitch, H.D. 2004 Environmental control of garlic growth and florogenesis J. Amer. Soc. Hort. Sci. 129 144 151
Keller, E.R.J. 2002 Cryopreservation of Allium sativum L. (garlic) 37 47 Towill L.E. & Bajaj Y.P.S. Biotechnology in agriculture and forestry, cryopreservation of plant germplasm II Springer-Verlag Berlin, Germany
Lampasona, S.G. , Martinez, L. & Burba, J.L. 2003 Genetic diversity among selected Argentenian garlic clones (Allium sativum L.) using AFLP (amplified fragment length polymorphism) Euphytica 132 115 119
Lawson, L.D. 1993 Bioactive organosulfur compounds of garlic and garlic products: Role in reducing blood lipids 306 330 Kinghorn A.D. & Balandrin M.F. Human medicinal agents from plants. Vol. ACS Symp. Ser. 534 Am. Chem. Soc. Books Washington, DC Chem. Abst. 119 (1993) 216 610.
- Search Google Scholar
- Export Citation
Lawson, L.D. 1993 Bioactive organosulfur compounds of garlic and garlic products: Role in reducing blood lipids 306 330 Kinghorn A.D. Balandrin M.F. Am. Chem. Soc. Books Washington, DC Chem. Abst. 119 (1993) 216 610.
Lawson, L.D. 1996 The chemical composition and chemistry of garlic cloves and processed garlic 37 107 Koch H.P. & Lawson L.D. Garlic. The science and therapeutic application of Allium sativum L. and related species Williams & Wilkins Baltimore, MD
Lot, H. , Chovelon, V. , Souche, S. & Delecolle, B. 1998 Effects of onion yellow dwarf and leek yellow stripe viruses on symptomatology and yield loss of three French garlic cultivars Plant Dis. 82 1381 1385
Maaß, H.I. & Klaas, M. 1995 Infraspecific differentiation on garlic (Allium sativum L.) by isozyme and RAPD markers Theor. Appl. Genet. 91 89 97
Melo, P.D. , Resende, R.O. , Cordeiro, C.M.T. , Buso, J.A. , Torres, A.C. & Dusi, A.N. 2006 Viral reinfection affecting bulb production in garlic after seven years of cultivation under field conditions Eur. J. Plant Pathol. 116 95 101
Panthee, D.R. , KC, R.B. , Regmi, H.N. , Subedi, P.P. , Bhattarai, S. & Dhakal, J. 2006 Diversity analysis of garlic (Allium sativum L.) germplasms available in Nepal based on morphological characters Genet. Resources Crop Evol. 53 205 212
Pardo, J.E. , Escribano, J. , Gomez, R. & Alvarruiz, A. 2007 Physical-chemical and sensory quality evaluation of garlic cultivars J. Food Qual. 30 609 622
Pooler, M.R. & Simon, P.W. 1993a Characterization and classification of isozyme and morphological variation in a diverse collection of garlic clones Euphytica 68 121 130
Pooler, M.R. & Simon, P.W. 1993b Garlic flowering in response to clone, photoperiod, growth temperature, and cold-storage HortScience 28 1085 1086
Randle, W.M. , Kopsell, D.E. & Kopsell, D.A. 2002 Sequentially reducing sulfate fertility during onion growth and development affects bulb flavor at harvest HortScience 37 118 121
Randle, W.M. , Lancaster, J.E. , Shaw, M.L. , Sutton, K.H. , Hay, R.L. & Bussard, M.L. 1995 Quantifying onion flavor compounds responding to sulfur fertility-sulfur increases levels of alk(en)yl cysteine sulfoxides and biosynthetic intermediates J. Amer. Soc. Hort. Sci. 120 1075 1081
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- Export Citation
Randle, W.M. Lancaster, J.E. Shaw, M.L. Sutton, K.H. Hay, R.L. Bussard, M.L. 1995 Quantifying onion flavor compounds responding to sulfur fertility-sulfur increases levels of alk(en)yl cysteine sulfoxides and biosynthetic intermediatesJ. Amer. Soc. Hort. Sci. 120 1075 1081
Rosen, C. , Becker, R. , Fritz, V. , Hutchison, B. , Percich, J. , Tong, C. & Wright, J. 2008 Growing garlic in Minnesota. Extension Bulletin 18 June 2009 <http://www.extension.umn.edu/distribution/cropsystems/DC7317.html>.
Shemesh, E. , Scholten, O. , Rabinowitch, H.D. & Kamenetsky, R. 2008 Unlocking variability: Inherent variation and developmental traits of garlic plants originated from sexual reproduction Planta 227 1013 1024
Stavelikova, H. 2008 Morphological characteristics of garlic (Allium sativum L.) genetic resources collection—Information Horticultural Sci. 35 130 135
Volk, G.M. , Henk, A.D. & Richards, C.M. 2004 Genetic diversity among US garlic clones as detected using AFLP methods J. Amer. Soc. Hort. Sci. 129 559 569
Waterer, D. & Schmitz, D. 1994 Influence of variety and cultural practices on garlic yields in Saskatchewan Can. J. Plant Sci. 74 611 614