Economic Botany

, Volume 65, Issue 1, pp 76–84 | Cite as

The Role of Organic Acids in the Domestication of Oxalis tuberosa: A New Model for Studying Domestication Resulting in Opposing Crop Phenotypes1

  • E. Jane BradburyEmail author
  • Eve Emshwiller


The Role of Organic Acids in the Domestication ofOxalis tuberosa: A New Model for Studying Domestication Resulting in Opposing Crop Phenotypes. Though few crops display directly opposing domesticated phenotypes, these crops may be the key to understanding domestication processes that address conflicting selective pressures in the agricultural ecosystem. Two relatively well-known examples are cassava (Manihot esculenta Crantz), which has high-cyanide and low-cyanide varieties, and potato (Solanum section Petota). Among the potatoes are several species, including the common potato (Solanum tuberosum L.), that have low levels of glycoalkaloids and there are other species of “bitter potato” with elevated levels of glycoalkaloids. We propose that Oxalis tuberosa Molina, “oca,” may represent a third example of such a crop system, with opposing high organic acid and low organic acid cultivars. Each cultivar set has different cultural food preparation practices (“use-categories”), similar to the “use-categories” that have been described for potatoes in the Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Our initial analyses suggest that organic acids in tubers may be an important biochemical difference between use-categories, based on both oxalic acid and pH data. Here, we review our understanding of organic acids in oca tubers, while highlighting areas that merit further investigation.

Key Words

Oxalis tuberosa domestication artificial selection oxalic acid organic acids folk classification Manihot esculenta Solanum section Petota Peru 


Los ácidos orgánicos y la domesticación de Oxalis tuberosa: un nuevo modelo para el estudio de la domesticación que resulta en los fenotipos domésticos opuestos. Aunque pocos cultivos presentan fenotipos domésticos directamente opuestos , estos cultivos pueden ser la clave para entender los procesos de domesticación que muestran conflicto en la presión selectiva en el ecosistema agrícola. Dos ejemplos relativamente bien conocidos son la yuca (Manihot esculenta Crantz), que tiene variedades de alto y bajo contenido de cianuro, y la papa (Solanum sección Petota). Entre las papas hay varias especies, incluyendo la papa común (Solanum tuberosum L.), que tienen bajos niveles de glicoalcaloides mientras otras especies como las "papas amargas", tienen elevados niveles de glicoalcaloides. Nosotros proponemos que Oxalis tuberosa Molina, oca, puede representar un tercer ejemplo de este sistema de cultivo, con niveles altos y bajos de ácidos orgánicos. Cada grupo de variedades de oca tiene diferentes practicas culturales respecto a su preparación como alimentos (categorías de uso), similar a las categorías de uso que se han descrito para las papas en los Andes (Brush et al. Economic Botany 35;70–88, 1981; Zimmerer Journal of Biogeography 18;165–178, 1991). Los análisis iniciales sugieren que los ácidos orgánicos en los tubérculos pueden deberse a una diferencia bioquímica importante entre el uso de categorías basadas en el ácido oxálico y los datos de pH. En este artículo examinamos nuestra interpretación de los ácidos orgánicos en los tubérculos de oca, además de destacar las áreas que merecen mayor investigación.



The authors thank David Tay, Carlos Arbizu, and Francisco Vivanco for providing oca tubers for testing and for granting access to CIP’s germplasm collection and trial fields; Cécile Ané for her indispensable help with statistical analyses; and Kandis Elliot for her help with our figures.

Literature Cited

  1. Albihn, P. B. E. and G. P. Savage. 2001a. The effect of cooking on the location and concentration of oxalate in three cultivars of New Zealand-grown oca (Oxalis tuberosa Mol). Journal of the Science of Food and Agriculture 81:1027–1033.CrossRefGoogle Scholar
  2. ——— and ———. 2001b. The bioavailability of oxalate from oca (Oxalis tuberosa). Journal of Urology 166:420–422.PubMedCrossRefGoogle Scholar
  3. Brush, S. B., H. J. Carney, and Z. Huamán. 1981. Dynamics of Andean potato agriculture. Economic Botany 35:70–88.CrossRefGoogle Scholar
  4. de Azkue, D. and A. Martínez. 1990. Chromosome number of the Oxalis tuberosa alliance (Oxalidaceae). Plant Systematics and Evolution 1:25–29.CrossRefGoogle Scholar
  5. de Wet, J. and J. Harlan. 1975. Weeds and domesticates. Evolution in the man-made habitat. Economic Botany 29:99–107.CrossRefGoogle Scholar
  6. Doebley, J. 2006. Plant science—Unfallen grains: How ancient farmers turned weeds into crops. Science 312(5778):1318–1319.PubMedCrossRefGoogle Scholar
  7. ——— 2009. Evolution under domestication: Examples from maize and other crops. Mechanisms of Development 126:S14.CrossRefGoogle Scholar
  8. Duke, J. A. 1992. Handbook of phytochemical constituents of GRAS herbs and other economic plants. CRC, Boca Raton.Google Scholar
  9. Elias, M. L., P. Penet, D. Vindry, D. McKey, O. Panaud, and T. Robert. 2001. Unmanaged sexual reproduction and the dynamics of genetic diversity of a vegetatively propagated crop plant, cassava (Manihot esculenta Crantz), in a Traditional Farming System. Molecular Ecology 10:1895–1907.PubMedCrossRefGoogle Scholar
  10. Emshwiller, E. 2006. Evolution and conservation of clonally propagated crops: Insights from AFLP data and folk taxonomy of the Andean tuber oca (Oxalis tuberosa). Pages 308–346 in T. J. Motley, N. Zerega, and H. Cross, eds., Darwin’s Harvest: New Approaches to the Origins, Evolution, and Conservation of Crops. Columbia University Press, New York.Google Scholar
  11. ——— and J. J. Doyle. 2002. Origins of domestication and polyploidy in oca (Oxalis tuberosa: Oxalidaceae). 2. Chloroplast–expressed glutamine synthetase data. American Journal of Botany 89(7):1042–1056.CrossRefGoogle Scholar
  12. ———, T. Theim, A. Grau, V. Nina, and F. Terrazas. 2009. Origins of domestication and polyploidy in oca (Oxalis tuberosa: Oxalidaceae). 3. AFLP data of oca and four, wild, tuber-bearing taxa. American Journal of Botany 96(10):1839–1848.CrossRefGoogle Scholar
  13. Flores, H., T. S. Walker, R. L. Guimaraes, H. P. Bais, and J. M. Vivanco. 2003. Andean root and tuber crops: Underground rainbows. Horticultural Science 38(2):161–167.Google Scholar
  14. Franceschi, V. R. and P. A. Nakata. 2005. Calcium oxalate in plants: Formation and function. Annual Review of Plant Biology 56:41–71.PubMedCrossRefGoogle Scholar
  15. Futuyma, D. J. 1998. Evolutionary Biology, 3rd edition. Sinauer, Sunderland.Google Scholar
  16. Gavrilenko, T. A., O. Y. Antoneva, and L. I. Kostina. 2007. Study of genetic diversity in potato cultivars using PCR analysis of organelle DNA. Russian Journal of Genetics 43(11):1301–1305.CrossRefGoogle Scholar
  17. Gepts, P. 2004. Crop domestication as a long-term selection experiment. Plant Breeding Reviews 24(2):1–44.Google Scholar
  18. Gregory, T. R. 2009. Artificial selection and domestication: Modern lessons from Darwin’s enduring analogy. Evolution: Education and Outreach 2(1):5–27.CrossRefGoogle Scholar
  19. Hatch, M. and R. W. Freel. 1995. Oxalate transport across intestinal and renal epithelia. Pages 217–278 in S. Kahn, ed., Calcium Oxalate in Biological Systems. CRC, Boca Raton.Google Scholar
  20. Hermann, M. and C. Erazo. 2000. Compositional changes of oca tubers following postharvest exposure to sunlight. CIP Program Report: 1999–2000:391–396.Google Scholar
  21. Hodgkinson, A. 1977. Oxalic acid in biology and medicine. Academic, London.Google Scholar
  22. Johns, T. 1996. The origins of human diet and medicine: Chemical ecology. The University of Arizona Press, Tucson [First paperbound printing 1996, copyright 1990. Originally published as: With bitter herbs they shall eat it.].Google Scholar
  23. Kelsay, J. L. 1985. Effect of oxalic acid on calcium bioavailability. Pages 105–116 in C. Kies, ed., Nutritional Bioavailability of Calcium. American Chemical Society, Washington.CrossRefGoogle Scholar
  24. King, S. R. 1988. Economic botany of the Andean tuber crop complex: Lepidium meyenii, Oxalis tuberosa, Tropaeolum tuberosum, and Ullucus tuberosus. Ph.D. dissertation, City University of New YorkGoogle Scholar
  25. Libert, B. and V. R. Franceschi. 1987. Oxalate in crop plants. Journal of Agricultural and Food Chemistry 35:926–938.CrossRefGoogle Scholar
  26. Lovelace, F. E., C. H. Live, and D. M. McCoy. 1950. Age of animal in relation to the utilization of calcium and magnesium in the presence of oxalate. Archives of Biochemistry 27:48.PubMedGoogle Scholar
  27. Massey, L. K. 2007. Food oxalate: Factors affecting measurement, biological variation, and bioavailability. Journal of the American Dietetic Association 107:1191–1194.PubMedCrossRefGoogle Scholar
  28. McKey, D. and S. Beckerman. 1993. Chemical ecology, plant evolution, and traditional manioc cultivation systems. Pages 83–112 in C. M. Hladik, A. Hladik, O. F. Linares, H. Pagezy, A. Semple, and M. Hadley, eds., Tropical Forests, People, and Food Biocultural Interactions and Applications to Development. Parthenon Publishing Group and Paris: UNESCO, Carnforth.Google Scholar
  29. Morgan, J. 2005. Grower’s gift for yams. The Dominion Post, Wellington, New Zealand. 1 Sept. C3.Google Scholar
  30. Murillo, A., M. S. Campos, and G. Varela. 1972. Factors affecting digestibility, absorption, and retention of calcium. Effect of oxalate, ethylene diamine tetraacetic acid (disodium salt), nitrilotriacetic acid, lysine and protein quality. Revista Espanola de Fisiologia 28(2):115–123.PubMedGoogle Scholar
  31. National Research Council (NRC). 1989. Lost crops of the Incas: Little–known plants of the Andes with promise for worldwide cultivation. National Academy Press, Washington.Google Scholar
  32. Noonan, S. C. and G. P. Savage. 1999. Oxalic acid and its effects on humans. Asia Pacific Journal of Clinical Nutrition 8:64–74.CrossRefGoogle Scholar
  33. Peters, T., L. Apt, and J. F. Ross. 1971. Effect of phosphates upon iron absorption studied in normal human subjects and in an experimental model using dialysis. Gastroenterology 61:315–322.PubMedGoogle Scholar
  34. Quiros, C. F., S. B. Brush, D. S. Douches, K. S. Zimmerer, and G. Huestis. 1990. Biochemical and folk assessment of variability of Andean cultivated potatoes. Economic Botany 44:254–266.CrossRefGoogle Scholar
  35. Ross, A. B., G. P. Savage, R. J. Martin, and L. Vanhanen. 1999. Oxalates in oca (New Zealand yam) (Oxalis tuberosa Mol.). Journal of Agricultural and Food Chemistry 47(12):5019–5022.PubMedCrossRefGoogle Scholar
  36. Sangketkit, C., G. P. Savage, R. J. Martin, and S. L. Mason. 2001. Oxalate content of raw and cooked oca (Oxalis tuberosa). Journal of Food Composition and Analysis 14:389–397.CrossRefGoogle Scholar
  37. Singh, P. P. 1973. The oxalic acid content of Indian foods. Plant Foods for Human Nutrition. 22(3–4):335–347.Google Scholar
  38. Trivelli, C. 1996. Secondary crops in peasant economies: Minor tubers in the Peruvian Andes. M.Sc. Thesis, Department of Agricultural Economics and Rural Sociology, The Pennsylvania State University.Google Scholar
  39. Yoshihara, T., K. Sogawa, and R. Villareal. 1979. Comparison of oxalic acid concentration in rice varieties resistant and susceptible to the brown planthopper. International Rice Research Newsletter 4:10–11.Google Scholar
  40. ———, ———, M. D. Pathak, B. O. Juliano, and S. Sakamura. 1980. Oxalic acid as a sucking inhibitor of brown planthopper in rice (Delphacidae, Homoptera). Entomologia Experimentalis et Applicata 27(2):149–155.Google Scholar
  41. Zimmerer, K. S. 1991. The regional biogeography of native potato cultivars in highland Peru. Journal of Biogeography 18:165–178.CrossRefGoogle Scholar
  42. Zohary, D. 1971. Origin of South–west Asiatic cereals: Wheats, barley, oats, and rye. Pages 235–263 in P. H. Davies, P. C. Harper, and I. C. Hedge, eds., Plant Life of South–West Asia. Royal Botanical Society of Edinburgh, Edinburgh.Google Scholar
  43. ———, J. R. Harlan, and A. Vardi. 1969. The wild diploid progenitors of wheat and their breeding value. Euphytica 18:58–65.Google Scholar

Copyright information

© The New York Botanical Garden 2010

Authors and Affiliations

  1. 1.Botany DepartmentUniversity of Wisconsin-MadisonMadisonUSA

Personalised recommendations