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Phenotypic analysis of leaf colours from the USDA, ARS sweetpotato (Ipomoea batatas) germplasm collection

Published online by Cambridge University Press:  01 March 2019

D. Michael Jackson ,
H. F. Harrison ,
R. L. Jarret  and
P. A. Wadl
D. Michael Jackson*
Affiliation:
USDA, ARS, U. S. Vegetable Laboratory, Charleston, SC, USA
H. F. Harrison
Affiliation:
USDA, ARS, U. S. Vegetable Laboratory, Charleston, SC, USA
R. L. Jarret
Affiliation:
USDA, ARS, Plant Genetic Resources Conservation Unit, Griffin, GA, USA
P. A. Wadl
Affiliation:
USDA, ARS, U. S. Vegetable Laboratory, Charleston, SC, USA
*
*Corresponding author. E-mail: mike.jackson@ars.usda.gov
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Abstract

Leaf colour characteristics of 730 sweetpotato, Ipomoea batatas (L.) Lam. (Convolvulaceae), plant introduction (PI) accessions from the USDA sweetpotato germplasm collection were evaluated during 2012–2014. Colorimetry data for the abaxial and adaxial leaf surfaces were recorded using a tristimulus colorimeter and the CIE 1976 L*a*b* and CIE L*C*h* colour spaces. Most accessions (725 of 730 PIs) had dark-to-medium green leaves, but two PIs had totally purple leaves, and three PIs had yellow or yellow-green (chartreuse) leaves. For mature, field-grown green leaves, values for the red-green coordinate (a*) averaged −12.4 for the adaxial and −10.4 for the abaxial leaf surface. Values for the blue-yellow coordinate (b*) averaged 17.2 for the adaxial and 17.3 for the abaxial leaf surface. Hue angle (h*) for green leaves averaged 120.9° for the adaxial and 126.2° for the abaxial leaf surface. Colour saturation (Chroma, C*) averaged 21.3 for the adaxial and 20.2 for the abaxial leaf surface. Lightness (L*) averaged 35.4 for the adaxial and 47.2 for the abaxial leaf surface of green leaves. Late in the season, over one-half (53.9%) of the 730 PIs showed some level of purple pigmentation in the leaf lamina. Late-season purple leaves were collected and colour coordinates were recorded for 118 PIs grown in the field. For purple leaves, values for a*, b*, C*, L* and h* averaged 2.3, 6.2, 7.9, 28.2 and 64.4° for the adaxial surface and −1.0, 12.7, 13.9, 43.1 and 87.0° for the abaxial leaf surface, respectively.

Keywords

anthocyanincolour spaceConvolvulaceaegenetic diversityphenomephenotypingplant introductions
Type
Research Article
Information
Plant Genetic Resources , Volume 17 , Issue 4 , August 2019 , pp. 325 - 338
Copyright
Copyright © NIAB 2019 

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Footnotes

The use of trade, firm or corporation names in this publication is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the United States Department of Agriculture or the Agricultural Research Service of any product or service to the exclusion of others that may be suitable.

References

Akoetey, W, Britain, MM and Morawicki, RO (2017) Potential use of byproducts from cultivation and processing of sweet potatoes. Ciência Rural, Santa Maria 47: e20160610, 8 pp.Google Scholar
Ameny, M and Wilson, P (1997) Relationship between hunter color values and β-carotene contents in white fleshed African sweet potatoes (Ipomoea batatas Lam.). Journal of the Science of Food and Agriculture 73: 301–306.Google Scholar
Anonymous (2018a) Command® 3ME microencapsulated herbicide. Specimen label. FMC Corporation, Philadelphia, Pennsylvania, USA, 19 pp. Available at http://www.cdms.net/ldat/ld324004.pdf (accessed 14 August 2018).Google Scholar
Anonymous (2018b) Descriptors for sweetpotato. United States Department of Agriculture, Agricultural Research Service, United States National Plant Germplasm System. Available at https://npgsweb.arsgrin.gov/gringlobal/cropdetail.aspx?type=descriptor&id=109 (accessed 14 August 2018).Google Scholar
Anonymous (2018c) Genebank: Cultivated Sweetpotato Germplasm Collection. International Potato Center (CIP), Lima, Peru. Available at https://cipotato.org/genebankcip/process/sweetpotato/sweet-cultivated/ (accessed 14 August 2018).Google Scholar
Anonymous (2018d) Sweetpotato. United States Department of Agriculture, Agricultural Research Service, United States National Plant Germplasm System. Available at https://npgsweb.ars-grin.gov/gringlobal/crop.aspx?id=109 (accessed 14 August 2018).Google Scholar
Anonymous (2018e) Sweet Potato Ontology. Crop Ontology Curation Tool. Available at http://www.cropontology.org/ontology/CO_331/Sweet%20Potato (accessed 14 August 2018).Google Scholar
Arias, R, Lee, T-C, Logendra, L and Janes, H (2000) Correlation of lycopene measured by HPLC with the L*, a*, b* color readings of a hydroponic tomato and the relationship of maturity with color and lycopene content. Journal of Agricultural and Food Chemistry 48: 1697–1702.Google Scholar
Armitage, AM and Garner, JM (2001) Ipomoea batatas ‘Margarita’. HortScience 36: 178.Google Scholar
Bolger, M, Schwacke, R, Gundlach, H, Schmutzer, T, Chen, J, Arend, D, Oppermann, M, Weise, S, Lange, M, Fiorani, F, Spannagl, M, Scholz, U, Mayer, K and Usadel, B (2017) From plant genomes to phenotypes. Journal of Biotechnology 261: 46–52.Google Scholar
Carey, D, Whipker, BE, Bradley, LK and Buhler, WG (2012) Ornamental sweetpotatoes for the home landscape. AG-755, North Carolina Cooperative Extension Service. Available at https://content.ces.ncsu.edu/ornamental-sweetpotatoes-for-the-home-landscape (accessed 14 August 2018).Google Scholar
Carvalho, IS, Cavaco, T, Carvalho, LM and Duque, P (2010) Effect of photoperiod on flavonoid pathway activity in sweet potato (Ipomoea batatas (L.) Lam.) leaves. Food Chemistry 118: 384–390.Google Scholar
Chalfant, RB, Jansson, RK, Seal, DR and Schalk, JM (1990) Ecology and management of sweet potato insects. Annual Review of Entomology 35: 157–180.Google Scholar
Chao, P-Y, Huang, Y-P and Hsieh, W-B (2013) Inhibitive effect of purple sweet potato leaf extract and its components on cell adhesion and inflammatory response in human aortic endothelial cells. Cell Adhesion and Migration 7: 237–245.Google Scholar
Chao, P-Y, Lin, S-Y, Lin, K-H, Liu, Y-F, Hsu, J-I, Yang, C-M and Lai, J-Y (2014) Antioxidant activity in extracts of 27 indigenous Taiwanese vegetables. Nutrients 6: 2115–2130.Google Scholar
Chen, C-M, Li, S-C, Lin, Y-L, Hsu, C-Y, Shieh, M-J and Liu, J-F (2005) Consumption of purple sweet potato leaves modulates human immune response: t-lymphocyte functions, lytic activity of natural killer cell and antibody production. World Journal of Gastroenterology 11: 5777–5781.Google Scholar
Claessens, L, Stoorvogel, JJ and Antle, JM (2009) Ex ante assessment of dual-purpose sweet potato in the crop-livestock system of western Kenya: a minimum-data approach. Agricultural Systems 99: 13–22.Google Scholar
Clark, CA, Ferrin, DM, Smith, TP and Holmes, GJ (2013) Compendium of Sweetpotato Diseases, Pests, and Disorders. St. Paul, Minnesota, USA: APS Press, American Phytopathological Society, 160 pp.Google Scholar
Close, DC and Beadle, CL (2003) The ecophysiology of foliar anthocyanin. The Botanical Review 69: 149–161.Google Scholar
de Pascual-Teresa, S and Sanchez-Ballesta, MT (2008) Anthocyanins: from plant to health. Phytochemistry Reviews 7: 281–299.Google Scholar
Dwivedi, SL, Scheben, A, Edwards, D, Spillane, C and Ortiz, R (2017) Assessing and exploiting functional diversity in germplasm pools to enhance abiotic stress adaptation and yield in cereals and food legumes. Frontiers in Plant Science 8: Article 1461, 30 pp.Google Scholar
Gibson, RW, Mpembe, I, Alicai, T, Carey, EE, Mwanga, ROM, Seal, SE and Vetten, HJ (1998) Symptoms, aetiology and serological analysis of sweet potato virus disease in Uganda. Plant Pathology 47: 95–102.Google Scholar
Gould, KS (2004) Nature's Swiss army knife: the diverse protective roles of anthocyanins in leaves. BioMed Research International 5: 314–320.Google Scholar
Gould, KS, Davies, KM and Winefield, C (2009) Anthocyanins: Biosynthesis, Functions, and Applications. New York, USA: Springer, 336 pp.Google Scholar
Gregory, P (1987) Exploration, maintenance, and utilization of sweet potato genetic resources. Report of the First Sweet Potato Planning Conference, 23–27 February 1987. International Potato Center (CIP), Lima, Peru, 369 pp.Google Scholar
Harrison, HF and Jackson, DM (2011) Greenhouse assessment of differences in clomazone tolerance among sweetpotato cultivars. Weed Technology 25: 501–505.Google Scholar
Hualla, VR, Simon, R, Mwanga, R, Soto, HSJ and Montesinos, GR (2015) The sweetpotato ontology. Metadata and ubiquitous access to culture. In: Proceedings DCMI International Conference on Dublin Core and Metadata Applications. 1–4 September 2015, Sao Paulo, Brazil, pp. 206–208. Available at http://hdl.handle.net/10568/72497 (accessed 14 August 2018).Google Scholar
Huamán, Z (1991) Descriptors for sweet potato. International Board for Plant Genetic Resources, Rome, Italy, 134 p. Available at https://www.bioversityinternational.org/fileadmin/_migrated/uploads/tx_news/Descriptors_for_sweet_potato_Descripteurs_pour_la_patate_douce_Descriptores_de_la_batata_263.pdf (accessed 14 August 2018).Google Scholar
Huamán, Z, Aguilar, C and Ortiz, R (1999) Selecting a Peruvian sweetpotato core collection on the basis of morphological, eco-geographical, and disease and pest reaction data. Theoretical and Applied Genetics 98: 840–844.Google Scholar
Huang, Y-J, To, K-Y, Yap, M-N, Chiang, W-J, Suen, D-F and Chen, S-CG (2001) Cloning and characterization of leaf senescence up-regulated genes in sweet potato. Physiologia Plantarum 113: 384–391.Google Scholar
Hue, S-M, Boyce, AN and Somasundram, C (2011) Influence of growth stage and variety on the pigment levels in Ipomoea batatas (sweet potato) leaves. African Journal of Agricultural Research 6: 2379–2385.Google Scholar
Hue, S-M, Boyce, AN and Somasundram, C (2012) Antioxidant activity, phenolic and flavonoid contents in the leaves of different varieties of sweet potato (Ipomoea batatas). Australian Journal of Crop Science 6: 375–380.Google Scholar
Hue, S-M, Boyce, AN and Somasundram, C (2014) Extraction from agricultural waste, Ipomoea batatas L. Lam leaves as a cheap source of natural dye. International Journal of Environmental Bioremediation and Biodegradation 2: 1–4.Google Scholar
Humplík, JF, Lazár, D, Husiíková, A and Spíchal, L (2015) Automated phenotyping of plant shoots using imaging methods for analysis of plant stress responses – a review. Plant Methods 11: 29.Google Scholar
Hunt, RWG (1991) Measuring Colour Ellis Horwood Series in Applied Science and Industrial Technology, 2nd edn. Chichester, UK: Ellis Horwood Ltd., 313 pp.Google Scholar
Hunter, RS and Harold, RW (1987) The Measurement of Appearance, 2nd edn. New York, USA: Wiley-Interscience Publ, John Wiley & Sons, Inc, 411 pp.Google Scholar
HunterLab (2009a) CIE L*a*b* color scale. Application note, insight on color 8:1–4. Available at http://www.hunterlab.com/appnotes/an07_96a.pdf (accessed 14 August 2018).Google Scholar
HunterLab (2009b) CIE L*C*h color scale. Application note, insight on color 8:1–4. Available at http://www.hunterlab.com/appnotes/an09_96a.pdf (accessed 14 August 2018).Google Scholar
Ishida, H, Suzuno, H, Sugiyama, N, Innami, S, Tadokoro, T and Maekawa, A (2000) Nutritive evaluation on chemical components of leaves, stalks and stems of sweet potatoes (Ipomoea batatas poir). Food Chemistry 68: 359–367.Google Scholar
Ishiguro, K, Toyama, J, Islam, MS, Yoshimoto, M, Kumagai, T, Kai, Y, Nakazawa, Y and Yamakawa, O (2004) Suioh, a new sweetpotato cultivar for utilization in vegetable greens. ISHS Acta Horticulturae 637: 339–367.Google Scholar
Islam, MS (2006) Sweetpotato (Ipomoea batatas L.) leaf: its potential effect on human health and nutrition. Journal of Food Science 71: R13–R21.Google Scholar
Islam, MS, Yoshimoto, M, Terahara, N and Yamakawa, O (2002a) Anthocyanin compositions in sweetpotato (Ipomoea batatas L.) leaves. Bioscience, Biotechnology, and Biochemistry 66: 2483–2486.Google Scholar
Islam, MS, Yoshimoto, M, Yahara, S, Okuno, S, Ishiguro, K and Yamakawa, O (2002b) Identification and characterization of foliar polyphenolic composition in sweetpotato (Ipomoea batatas L.) genotypes. Journal of Agricultural and Food Chemistry 50: 3718–3722.Google Scholar
Islam, MS, Yoshimoto, M, Ishiguro, K and Yamakawa, O (2003) Bioactive compounds in Ipomoea batatas leaves. ISHS Acta Horticulturae 628: 693–699.Google Scholar
Islam, MS, Jalaluddin, M, Garner, JO, Yoshimoto, M and Yamakawa, O (2005) Artificial shading and temperature influence on anthocyanin compositions in sweetpotato leaves. HortScience 40: 176–180.Google Scholar
Jackson, DM, Harrison, HF, Jarret, RL and Wadl, PA (2018a) Color analysis of storage roots from the USDA, ARS sweetpotato germplasm collection. Genetic Resources and Crop Evolution 65: 1217–1236.Google Scholar
Jackson, DM, Harrison, HF, Jarret, RL and Wadl, PA (2018b) Data from: Color analysis of sweetpotato leaves from the USDA, ARS germplasm collection. Ag Data Commons Beta, United States Department of Agriculture, Agricultural Research Service, National Agriculture Library. Available at https://data.nal.usda.gov/dataset/data-color-analysis-sweetpotato-leaves-usda-ars-germplasm-collection (accessed 14 August 2018).Google Scholar
Johnson, M and Pace, RD (2010) Sweet potato leaves: properties and synergistic interactions that promote health and prevent disease. Nutrition Reviews 68: 604–615.Google Scholar
Johnson, ET, Berhow, MA and Dowd, PF (2008) Colored and white sectors from star-patterned petunia flowers display differential resistance to corn earworm and cabbage looper larvae. Journal of Chemical Ecology 34: 757–765.Google Scholar
Karageorgou, P and Manetas, Y (2006) The importance of being red when young: anthocyanins and the protection of young leaves of Quercus coccifera from insect herbivory and excess light. Tree Physiology 26: 613–621.Google Scholar
Karna, P, Gundala, SR, Gupta, MV, Shamsi, SA, Pace, RD, Yates, C, Narayan, S and Aneja, R (2011) Polyphenol-rich sweet potato greens extract inhibits proliferation and induces apoptosis in prostate cancer cells in vitro and in vivo. Carcinogenesis 32: 1872–1880.Google Scholar
Khoo, H-E, Prasad, KN, Kong, K-W, Jiang, Y and Ismail, A (2011) Carotenoids and their isomers: color pigments in fruits and vegetables. Molecules 16: 1710–1738.Google Scholar
Konica-Minolta (2007a) Chroma meter CR-400/410, instruction manual. Konica Minolta Sensing, Inc., Tokyo, Japan. Available at https://sensing.konicaminolta.us/uploads/cr-400-410_instruction_eng-8260×153f3.pdf (Accessed 14 August 2018).Google Scholar
Konica-Minolta (2007b) Color data software CMS100w Spectra MagicNX Version 1.7, instruction manual. Konica Minolta Sensing, Inc., Tokyo, Japan. Available at https://www.konicaminolta.com/instruments/download/software/color/smnx/index.html (Accessed 14 August 2018).Google Scholar
Lee, J-S, Park, Y-K, Ahn, Y-S, Kim, H-S, Chung, M-N, Jeong, B-C and Bang, J-K (2007) Antioxidative and biological activities of extracts of sweetpotato tips. Korean Journal of Crop Science 52: 411–420.Google Scholar
Levene, H (1960) Robust tests for equality of variances. In: Olkin, I, Ghurye, SG, Hoeffding, W, Madow, WG and Mann, HB (eds) Contributions to Probability and Statistics: Essays in Honor of Harold Hotelling. Palo Alto, California, USA: Stanford University Press, pp. 278–292.Google Scholar
Lev-Yadun, S and Gould, KS (2008) Role of anthocyanins in plant defense. In: Winefield, C, Davies, K and Gould, K (eds) Anthocyanins: Biosynthesis, Functions, and Applications. New York, USA: Springer, pp. 22–28.Google Scholar
Liao, WC, Lai, Y-C, Yuan, M-C, Hsu, Y-L and Chan, C-F (2011) Antioxidative activity of water extract of sweet potato leaves in Taiwan. Food Chemistry 127: 1224–1228.Google Scholar
Luo, C-L, Zhou, Q, Yang, Z-W, Wang, R-D and Zhang, J-L (2018) Evaluation of structure and bioprotective activity of key high molecular weight acylated anthocyanin compounds isolated from the purple sweet potato (Ipomoea batatas L. cultivar Eshu No. 8). Food Chemistry 241: 23–31.Google Scholar
McGuire, RG (1992) Reporting of objective color measurements. HortScience 27: 1254–1255.Google Scholar
McLaren, K (1976) XIII-The development of the CIE 1976 (L*a*b*) uniform colour space and colour-difference formula. Journal of the Society of Dyers and Colourists 92: 338–341.Google Scholar
Menelaou, E, Kachatryan, A, Losso, JN, Cavalier, M and LaBonte, D (2006) Lutein content in sweetpotato leaves. HortScience 41: 1269–1271.Google Scholar
Mohanraj, R and Sivasankar, S (2014) Sweet potato (Ipomoea batatas [L.] Lam) – A valuable medicinal food: a review. Journal of Medicinal Food 17: 733–741.Google Scholar
Mortley, DG, Burrell, S, Bonsi, CK, Hill, WA and Morris, CE (2009) Influence of daily light period and irradiance on yield and leaf elemental concentration of hydroponically grown sweetpotato. HortScience 44: 1491–1493.Google Scholar
Moyer, JW and Salazar, LF (1989) Viruses and virus-like diseases of sweet potato. Plant Disease 73: 451–455.Google Scholar
Murugan, S, Paramasivam, SK and Nedunchezhiyan, M (2012) Sweet potato as an animal feed and fodder. In: Nedunchezhiyan, M and Byju, G (eds), Sweet Potato. Fruit, Vegetable and Cereal Science and Biotechnology 6 (Special Issue 1). Ikenobe, Japan: Global Sci Books, Ltd, UK, pp. 106–114.Google Scholar
Mussoline, EA and Wilkie, AC (2017) Feed and fuel: the dual-purpose advantage of an industrial sweetpotato. Journal of the Science of Food and Agriculture 97: 1567–1575.Google Scholar
Niyireba, TN, Ebong, C, Agili, S, Low, J, Lukuyu, B, Kirui, J, Ndirigwe, J, Uwimana, G, Kakundiye, L, Mutimura, M, Gahakwa, D and Gachuiri, CK (2013) Evaluation of dual purpose sweet potato [Ipomoea batatas (L.) Lam] cultivars for root and fodder production in Eastern province Rwanda. Agricultural Journal 8: 242–247.Google Scholar
Ojong, PB, Njiti, V, Guo, Z, Gao, M, Besong, S and Barnes, SL (2008) Variation of flavonoid content among sweetpotato accessions. Journal of the American Society for Horticultural Science 133: 819–824.Google Scholar
Oren-Shamir, M (2009) Does anthocyanin degradation play a significant role in determining pigment concentration in plants? Plant Science 177: 310–316.Google Scholar
Oren-Shamir, M and Levi-Nissim, A (1997) Temperature effects on the leaf pigmentation of Cotinus coggygria ‘Royal purple’. Journal of Horticultural Science 72: 425–432.Google Scholar
Pace, RD, Dull, GG, Phills, BR, Bonsi, C and Forrester, IT (1988) The effect of topping frequency on nutrient content of sweet potato green tips. Journal of Food Composition and Analysis 1: 326–333.Google Scholar
Pathare, PB, Opara, UL and Al-Said, FAJ (2013) Colour measurement and analysis in fresh and processed foods: a review. Food and Bioprocess Technology 6: 36–60.Google Scholar
Pecota, K, Yencho, GC and Pierce, C (2004a) Ornamental sweetpotato plant named ‘Sweet Caroline Purple’. United States Patent Number US PP14,912 P3. Available at http://www.google.com/patents/USPP14912 (Accessed 14 August 2018).Google Scholar
Pecota, K, Yencho, GC and Pierce, C (2004b) Ornamental sweetpotato plant named ‘Sweet Caroline Light Green’. United States Patent Number US PP15,028 P2. Available at http://www.google.com/patents/USPP15028 (Accessed 14 August 2018).Google Scholar
Pecota, K, Yencho, GC and Pierce, C (2004c) Ornamental sweetpotato plant named ‘Sweet Caroline Bronze’. United States Patent Number US PP15,437 P3. Available at http://www.google.com/patents/USPP15437 (Accessed 14 August 2018).Google Scholar
Pecota, K, Yencho, GC and Hancock, CN Jr (2007) Ornamental sweetpotato plant named ‘Sweet Caroline Red. United States Patent Number US PP17,483 P3. Available at http://www.google.com/patents/USPP17483 (Accessed 14 August 2018).Google Scholar
Prokopy, RJ and Owens, ED (1983) Visual detection of plants by herbivorous insects. Annual Review of Entomology 28, 337–364.Google Scholar
Quisenberry, SS and Ni, X (2007) Feeding injury. In: van Emden, H and Harrington, R (eds) Aphids as Crop Pests. Oxford, UK: CABI, Oxford University Press, pp. 331–352.Google Scholar
Ravi, V and Saravanan, R (2012) Crop physiology of sweet potato. In: Nedunchezhiyan, M and Byju, G (eds), Sweet Potato. Fruit, Vegetable and Cereal Science and Biotechnology 6 (Special Issue 1). Ikenobe, Japan: Global Science Books, Ltd, UK, pp. 17–29.Google Scholar
Roca, WM, Laliberté, B, Renoso, D, Rao, R and de Chavez, H (2007) Global Strategy for ex-Situ Conservation of Sweet Potato Genetic Resources. Lima, Peru: International Potato Center (CIP), 76 pp.Google Scholar
Rodríguez-Delfín, A, Posadas, A, León-Velarde, C, Mares, V and Quiroz, R (2011) Effect of salt and water stress on the proline and total chlorophyll content and nutrients uptake on two sweet potato cultivars grown on soilless culture. In: II International Symposium on Soilless Culture and Hydroponics. ISHS Acta Horticulturae 947: 55–62.Google Scholar
SAS (2009) SAS for Windows, Version 9.1. SAS Institute, Cary, North Carolina, USA. Available at https://support.sas.com/documentation/onlinedoc/91pdf/index.html (accessed 14 August 2018).Google Scholar
Si, Z, Du, B, Huo, J, He, S, Liu, Q and Zhai, H (2016) A genome-wide BAC-end sequence survey provides first insights into sweetpotato (Ipomoea batatas (L.) Lam.) genome composition. BMC Genomics 17: 945, 15 pp.Google Scholar
Simko, I, Jimenez-Berni, JA and Sirault, XRR (2017) Phenomic approaches and tools for phytopathologists. Phytopathology 107: 6–17.Google Scholar
Steyn, WJ, Wand, SJE, Holcroft, DM and Jacobs, G (2002) Anthocyanins in vegetative tissues: a proposed unified function in photoprotection. New Phytologist 155: 349–361.Google Scholar
Steel, RGD and Torrie, JH (1960) Principles and Procedures of Statistics. New York, USA: McGraw-Hill Book Company Incorporated, 481 pp.Google Scholar
Sun, H, Mu, T, Xi, L, Zhang, M and Chen, J (2014) Sweet potato (Ipomoea batatas L.) leaves as nutritional and functional foods. Food Chemistry 156: 380–389.Google Scholar
Tairo, F, Mneney, E and Kullaya, A (2008) Morphological and agronomical characterization of sweet potato [Ipomoea batatas (L.) Lam.] germplasm collection from Tanzania. African Journal of Plant Science 2: 77–85.Google Scholar
Tanaka, M, Ishiguro, K, Oki, T and Okuno, S (2017) Functional components in sweetpotato and their genetic improvement. Breeding Science 67: 52–61.Google Scholar
Truong, V-D, McFeeters, RF, Thompson, RT, Dean, LL and Shofran, B (2007) Phenolic acid content and composition in leaves and roots of common commercial sweetpotato (Ipomoea batatas L.) cultivars in the United States. Journal of Food Science 72: 343–349.Google Scholar
Tucker, AO, Maciarello, MJ and Tucker, SS (1991) A survey of color charts for biological descriptions. Taxon 40: 201–214.Google Scholar
Ustin, SL, Gitelson, AA, Jacquemoud, S, Schaepman, M, Asner, GP, Gamon, JA and Zarco-Tejada, P (2009) Retrieval of foliar information about plant pigment systems from high resolution spectroscopy. Remote Sensing of Environment 113: S67–S77.Google Scholar
Veasey, EA, Borges, A, Rosa, MS, Queiroz-Silva, JR, de Andrade Bressan, E and Peroni, N (2008) Genetic diversity in Brazilian sweet potato (Ipomoea batatas (L.) Lam) landraces assessed with microsatellite markers. Genetics and Molecular Biology 31: 725–733.Google Scholar
Villareal, RL, Tsou, SCS, Lin, SK and Chiu, SC (1979) Use of sweet potato (Ipomoea batatas) leaf tips as vegetables II. Evaluation of yield and nutritive quality. Experimental Agriculture 15: 117–122.Google Scholar
Voss, DH (1992) Relating colorimeter measurement of plant color to the royal horticultural society colour chart. HortScience 27: 1256–1260.Google Scholar
Wadl, PA, Olukolu, BA, Branham, SE, Jarret, RL, Yencho, GC and Jackson, DM (2018) Genetic diversity and population structure of the USDA sweetpotato (Ipomoea batatas) germplasm collections using GBSpoly. Frontiers in Plant Science 9, article 1166, 13 pp. Available at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6111789/pdf/fpls-09-01166.pdf (accessed 20 November 2018).Google Scholar
Wang, S, Nie, S and Zhu, F (2016) Chemical constituents and health effects of sweet potato. Food Research International 89: 90–116.Google Scholar
Weng, J-H, Chien, L-F, Jiang, C-Y, Shih, F-C and Chen, H-Y (2011) A comparison between yellow-green and green cultivars of four vegetable species in pigments, ascorbate, photosynthesis, energy dissipation, and photoinhibition. Photosynthetica 49: 361–370.Google Scholar
Woolfe, JA (1992) Sweet Potato: An Untapped Food Reserve. Cambridge University Press, Cambridge, UK, 643 pp.Google Scholar
Wyszecki, G and Stiles, WS (1982) Color Science: Concepts and Methods, Quantitative Data and Formulae, 2nd edn. New York, USA: Wiley-Interscience Publication, John Wiley & Sons, Incorporated, 949 pp.Google Scholar
Yencho, GC and Pecota, K (2008a) Ornamental sweetpotato plant named ‘Sweet Caroline Bewitched Purple’. United States Patent Number US PP18,574 P3. Available at http://www.google.com/patents/USPP18574 (Accessed 14 August 2018).Google Scholar
Yencho, GC and Pecota, K (2008b) Ornamental sweetpotato plant named ‘Sweet Caroline Green Yellow’. United States Patent Number US PP18,673 P3. Available at http://www.google.com/patents/USPP18673 (Accessed 14 August 2018).Google Scholar
Yencho, GC and Pecota, K (2008c) Ornamental sweetpotato plant named ‘Sweet Caroline Sweetheart Red’. United States Patent Number US PP19,013 P3. Available at http://www.google.com/patents/USPP19013 (Accessed 14 August 2018).Google Scholar
Yencho, GC, Pecota, K and Hancock, CN Jr (2008a) Ornamental sweetpotato plant named ‘Sweet Caroline Sweetheart Light Green’. United States Patent Number US PP18,572 P3. Available at http://www.google.com/patents/USPP18572 (Accessed 14 August 2018).Google Scholar
Yencho, GC, Pecota, K and Hancock, CN Jr (2008b) Ornamental sweetpotato plant named ‘Sweet Caroline Sweetheart Purple’. United States Patent Number US PP18,573 P3. Available at http://www.google.com/patents/USPP18573 (Accessed 14 August 2018).Google Scholar
Yoshimoto, M, Kurata, R, Okuno, S, Ishiguro, K, Yamakawa, O, Tsubata, M, Mori, S and Takagaki, K (2006) Nutritional value and physiological functions of sweetpotato leaves. ISHS Acta Horticulturae 703: 107–115.Google Scholar
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