Effect of EDTA-assisted Copper Uptake on Photosynthetic Activity and Biomass Production of Sweet Sorghum
Sweet sorghum (Sorghum bicolor L. Moench cv. Róna) is a widely grown sugar crop that is used for bioenergy production. Since sorghum shows increased sensitivity to nutrient deficiency, the objective of this study was to reach an appropriate Cu level in plant tissues using various concentrations of Cu and ethylenediaminetetraacetic acid (EDTA) in order to enhance the photosynthetic activity and biomass production of plants. Copper accumulation increased in the root and stem of plants irrigated for 12 weeks with 0.1 μM CuCl2 both in the presence and absence of 300 μM EDTA and as a consequence, the plant-available Cu concentration in the soil extracts was lower at harvest. Although the copper content of leaves slightly increased, the transport of Fe and Mn, the microelements participating in light reactions of photosynthesis was negatively affected. In spite of this, 0.1 μM CuCl2 alone and with 200 or 300 μM EDTA enhanced the maximal CO2 assimilation rate (Amax) as a function of photon flux density (PPFD) and increased soluble sugar content in all plant parts. The dry mass of plants especially that of stems increased very significantly after 0.1 μM CuCl2 + 300 μM EDTA treatment. These results show that non-toxic concentration of copper in combination with suitable concentration of EDTA can enhance photosynthesis, biomass production, sugar content and the total copper accumulation in the shoot of sweet sorghum plants.
Keywordsbiomass production copper accumulation microelements soluble sugars Sorghum
Unable to display preview. Download preview PDF.
This work was supported by the projects named “TÁMOP-4.2.1/B-09/1/KONV-2010-0005 - Creating the Center of Excellence at the University of Szeged” and TÁMOP-4.1.1.C-12/1/KONV-2012-0012 financed by the European Union and co-financed by the European Regional Fund (www.nfu.hu, www.okmt.hu). We thank Kispálné Szabó Ibolya and Ádámné Meszlényi Mária for their excellent technical assistance. We also thank Cereal Research Non-Profit Ltd., Szeged, Hungary for sweet sorghum seeds.
- Alloway, B.J. 2005. Copper Deficient Soils in Europe. Int. Copper Assoc. New York, USA. pp. 129.Google Scholar
- Angelova, V.R., Ivanova, R.V., Delibaltova, V.A., Ivanov, K.I. 2011. Use of Sorghum crops for in situ phytore-mediation of polluted soils. J. Agric. Sci. Technol. 1:693–702.Google Scholar
- Broadly, M., Brown, P., Cakmak I., Rengel Z., Zhao F. 2012. Function of nutrients: micronutrients. In: Marschner, P. (ed.), Mineral Nutrition of Higher Plants. Third Ed. Academic Press. London, UK. pp. 206–212.Google Scholar
- Feigl, G., Kumar, D., Lehotai, N., Tugyi, N., Molnár, Á., Ördög, A., Szepesi, Á., Gémes, K., Laskay, G., Erdei, L., Kolbert, Zs. 2013. Physiological and morphological responses of the root system of Indian mustard (Brassica juncea L. Czern.) and rapeseed (Brassica napus L.) to copper stress. Ecotox. Environ. Safety 94:179–189.CrossRefGoogle Scholar
- Győri, D. 1984. A talaj termékenysége (Soil fertility). In: Szabó, S.A., Regusiné, M., Csényi, Á., Győri, D. (eds), Mikroelemek a mezőgazdaságban (Microelements in Agriculture). Mezőgazdasági Kiadó. Budapest, Hungary. 235 p. (in Hungarian)Google Scholar
- Lakanen, E., Erviö, R. 1971. A comparison of eight extractants for the determination of plant available micronutrients in soils. Acta Agron. Fenn. 123:223–232.Google Scholar
- Ni, C.Y., Zeng, H., Jian, M.F., Zhu, D. 2009. Copper toxicity to Astragalus sinicus. Chinese J. Ecol. 4:0–13.Google Scholar
- Penney, D.C., Solberg, E.D., Evans, I.R., Piening, L.J. 1988. The copper fertility in Alberta soils. Great Plains Soil Fertility Workshop Proceedings, Vol. 2. Kansas State University. Manhatten, KS, USA. 66506. http://www1.agric.gov.ab.ca/department/deptdocs.nsf/all/agdex3476
- Poór, P., Gémes, K., Horváth, F., Szepesi, A., Simon, M. L., Tari, I. 2011. Salicylic acid treatment via the rooting medium interferes with stomatal response, CO2 fixation rate and carbohydrate metabolism in tomato, and decreases harmful effects of subsequent salt stress. Plant Biol. 13:105–114.CrossRefGoogle Scholar
- Tari, I., Poór, P., Ördög, A., Székely, Á., Laskay, G., Bagi, I. 2013b. Enhanced biomass production in sudangrass induced by co-treatment with copper and EDTA. Environ. Exp. Biol. 11:151–157.Google Scholar