Nutritional value of potato (Solanum tuberosum) in hot climates: anthocyanins, carotenoids, and steroidal glycoalkaloids
Growth in hot climates selectively alters potato tuber secondary metabolism—such as the anthocyanins, carotenoids, and glycoalkaloids—changing its nutritive value and the composition of health-promoting components.
Potato breeding for improved nutritional value focuses mainly on increasing the health-promoting carotenoids and anthocyanins, and controlling toxic steroidal glycoalkaloids (SGAs). Metabolite levels are genetically determined, but developmental, tissue-specific, and environmental cues affect their final content. Transcriptomic and metabolomic approaches were applied to monitor carotenoid, anthocyanin, and SGA metabolite levels and their biosynthetic genes’ expression under heat stress. The studied cultivars differed in tuber flesh carotenoid concentration and peel anthocyanin concentration. Gene expression studies showed heat-induced downregulation of specific genes for SGA, anthocyanin, and carotenoid biosynthesis. KEGG database mapping of the heat transcriptome indicated reduced gene expression for specific metabolic pathways rather than a global heat response. Targeted metabolomics indicated reduced SGA concentration, but anthocyanin pigments concentration remained unchanged, probably due to their stabilization in the vacuole. Total carotenoid level did not change significantly in potato tuber flesh, but their composition did. Results suggest that growth in hot climates selectively alters tuber secondary metabolism, changing its nutritive value and composition of health-promoting components.
KeywordsHigh growth temperature Phelloderm Secondary metabolite Transcriptome Tuber flesh
This work was supported by the Chief Scientist of the Ministry of Agriculture and Rural Development—Italian-Israel NUTRISOL project (261-0929-14), and is a contribution of the ARO, the Volcani Center, Israel. Authors would like to thank Dr. Mira Weisberg for the SGA metabolite analyses.
- Cárdenas PD, Sonawane PD, Pollier J, Vanden Bossche R, Dewangan V, Weithorn E, Tal L, Meir S, Rogachev I, Malitsky S, Giri AP, Goossens A, Burdman S, Aharoni A (2016) GAME9 regulates the biosynthesis of steroidal alkaloids and upstream isoprenoids in the plant mevalonate pathway. Nature Commun 7:10654CrossRefGoogle Scholar
- Itkin M, Heinig U, Tzfadia O, Bhide AJ, Shinde B, Cardenas PD, Bocobza SE, Unger T, Malitsky S, Finkers R, Tikunov Y, Bovy A, Chikate Y, Singh P, Rogachev I, Beekwilder J, Giri AP, Aharoni A (2013) Biosynthesis of antinutritional alkaloids in Solanaceous crops is mediated by clustered genes. Science 341:175–179CrossRefGoogle Scholar
- Lafta AM, Lorenzen JH (2000) Influence of high temperature and reduced irradiance on glycoalkaloid levels in potato leaves. J Amer Soc Hort Sci 125:563–566Google Scholar
- McCue KF, Shepherd LVT, Allen PV, Maccree MM, Rockhold DR, Corsini DL, Davies HV, Belknap WR (2005) Metabolic compensation of steroidal glycoalkaloid biosynthesis in transgenic potato tubers: using reverse genetics to confirm the in vivo enzyme function of a steroidal alkaloid galactosyltransferase. Plant Sci 168:267–273CrossRefGoogle Scholar
- Sawai S, Ohyama K, Yasumoto S, Seki H, Sakuma T, Yamamoto T, Takebayashi Y, Kojima M, Sakakibara H, Aoki T, Muranaka T, Saito K, Umemoto N (2014) Sterol side chain reductase 2 is a key enzyme in the biosynthesis of cholesterol, the common precursor of toxic steroidal glycoalkaloids in potato. Plant Cell 26:3763–3774CrossRefGoogle Scholar
- Stushnoff C, Ducreux LJM, Hancock RD, Hedley PE, Holm DG, McDougall GJ, McNicol JW, Morris J, Morris WL, Sungurtas JA, Verrall SR, Zuber T, Taylor MA (2010) Flavonoid profiling and transcriptome analysis reveals new gene-metabolite correlations in tubers of Solanum tuberosum L. J Exp Bot 61:1225–1238CrossRefGoogle Scholar
- Villavicencio LE, Blankenship SM, Yencho GC, Thomas JF, Raper CD (2007) Temperature effect on skin adhesion, cell wall enzyme activity, lignin content, anthocyanins, growth parameters, and periderm histochemistry of sweetpotato. J Am Soc Hortic Sci 132:729–738Google Scholar
- Yamaguchi M, Timm H, Spurr A (1964) Effects of soil temperature on growth and nutrition of potato plants and tuberization, composition, and periderm structure of tubers. Proc Amer Soc Hort Sci 84:412–423Google Scholar