Carbon Isotope Discrimination, A Tool for Screening of Salinity Tolerance of Genotypes

Authors: Alireza Dadkhah, Mahmoud Ghorbanzadeh- Neghab

Abstract:

This study carried out in order to investigate the effects of salinity on carbon isotope discrimination (Δ) of shoots and roots of four sugar beet cultivars (cv) including Madison (British origin) and three Iranian culivars (7233-P12, 7233-P21 and 7233-P29). Plants were grown in sand culture medium in greenhouse conditions. Plants irrigated with saline water (tap water as control, 50 mM, 150 mM, 250 mM and 350 mM of NaCl + CaCl2 in 5 to 1 molar ratio) from 4 leaves stage for 16 weeks. Carbon isotope discrimination significantly decreased with increasing salinity. Significant differences of Δ between shoot and root were observed in all cvs and all levels of salinity. Madison cv showed lower Δ in shoot and root than other three cvs at all levels of salinity expect control, but cv 7233-P29 had significantly higher Δ values at saline conditions of 150 mM and above. Therefore, Δ might be applicable, as a useful tool, for study of salinity tolerance of sugar beet genotypes.

Keywords: Carbon isotope discrimination, Photosynthesis, Salt stress, Sugar beet

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1056458

References:

[1] M.W. Hester, I.A. Mendelssohn, K.L. McKee. "Species and population variation to salinity stress in Panicum hemitomon, Spartina patens, and Spartina alterniflora: morphological and physiological constraints. Environmental and Experimental Botany, 46, 277-297. 2001.
[2] A. Dadkhah, H. Griffiths, "'Stomatal and non-stomatal components to inhibition of photosynthesis in leaves of sugar beet plants under salt stress". Iran Agricultural Research. 23, 35-50. 2004.
[3] M. Kafi, H. Griffiths, A. Nezami, H. R. Kazaie, and A. Sharif, "Effect of salinity on carbon isotope discrimination of shoot and grain of salttolerance and salt-snsitive wheat cultivars". Asian Journal of Plant Sciences, 6 (8): 1166-1173. 2007.
[4] G.D. Farquhar, J.R. Ehleringer, K.T. Hubick, "Carbon isotope discrimination and photosynthesis". Annual Review of Plant Physiology, 40, 503-537. 1989.
[5] G.D. Farquhar, and A.R. Richards, "Isotopic composition of plant carbon correlates with water-use efficiency of wheat genotypes". Australian Journal of Plant Physiology, 11, 539-552. 1984.
[6] G.D. Farquhar, , M.H. O'leary, J.A. Berry, "On the relationship between carbon isotope discrimination and the intercellular carbon dioxide concentration in leaves". Australian Journal of Plant Physiology, 9, 121- 137. 1982.
[7] K.T. Hubick, R.horter, G.D. Farquhar, "Heritability and genotype environmental interactions of carbon isotope discrimination and transpiration efficiency in diverse peanut (Arachis) germplasm". Australian Journal of Plant Physiology, 13, 803-816. 1988.
[8] N. Brugnoli, M. Lauteri, "Effect of salinity on stomatal conductance, photosynthesis capasity and carbon isotope discrimination of salt tolerant (Gossypium hirsutum L.) and salt sensitive (Phaseolus vulgaris L.) C3 nonhalophytes". Plant Physiology, 95, 628-635. 1991.
[9] S.L. Matzner, J.R. Kevin, J.H.Richards, "Factors affecting the relationship between carbon isotope discrimination and transpiration efficiency in blue oak (Quercus douglasii)". Australian Journal of Plant Physiology, 28, 49-56. 2001.
[10] E. Brugnoli, G.D.Farquhar, Photosynthetic fractionation of carbon isotope. In: Leegood, R.C., Sharky, T.D. and von Caemmerer, S. (eds), Advance in photosynthesis, photosynthesis: physiology and metabolism. Vol. 9. Kluwer Academic Publishers: The Netherlands, pp. 399-434. 2000.
[11] H-L. Schmidand, G.Gleixner, Carbon isotope effects on key reaction in plant metabolism and 13C-patterns in natural compounds". In: Griffiths, H. (ed.), Stable isotopes integration of biological, ecological and geochemical processes. 1998. BIOS Scientific Publishers, Oxford.