Abstract
Photosynthetic assimilation of 14CO2 was examined in leaves of potato (Solanum tuberosum L.) plants that were grown under direct sunlight and then transferred to 50% irradiance for various periods. The rate of 14CO2 assimilation correlated with light intensity: the photosynthetic rate reduced by 52% after 5-day shading and by 70% after 30-min shading. In all shaded and shade-adapted plants, the sucrose/hexose ratio decreased by a factor of 3.5–4.1; furthermore, the radioactivity of glycolate cycle metabolites and the serine/glycine ratio were lowered. In plants shaded for 5 days or 30 min, the radioactivity of aspartate and malate was higher than at continuous high irradiance, especially in plants shaded for 30 min, whereas a sudden illumination of the shaded plants reduced the radioactivity of these substances. We suppose that low irradiance averted the reentry of glycolate path carbon into the Calvin cycle and redirected this carbon source for the production of four-carbon acids that acidified the apoplast. This acidification activated the apoplastic invertase, which enhanced sucrose hydrolysis and hindered the sucrose export from the leaf. Hydrolysis of sucrose promoted the increase in osmolarity of the apoplastic solution, this increase being stronger at close distances to the stomatal pores where water is intensely evaporated. The increase in osmolarity of extracellular medium led to closing of stomata and the suppression of photosynthesis.
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Abbreviations
- PGA:
-
phosphoglyceric acid
References
Gandin, A., Denysyuk, M., and Asaph, B., Cousins disruption of the mitochondrial alternative oxidase (AOX) and uncoupling protein (UCP) alters rates of foliar nitrate and carbon assimilation in Arabidopsis thaliana, J. Exp. Bot., 2014, vol. 65, pp. 3133–3142.
Eichelmann, H., Oja, V., Peterson, R.B., and Laisk, A., The rate of nitrite reduction in leaves as indicated by O2 and CO2 exchange during photosynthesis, J. Exp. Bot., 2011, vol. 62, pp. 2205–2215.
Gandin, A., Duffes, C., Day, D.A., and Cousins, A.B., The absence of alternative oxidase AOX1A results in altered response of photosynthetic carbon assimilation to increasing CO2 in Arabidopsis thaliana, Plant Cell Physiol., 2012, vol. 53, pp. 1627–1637.
Novitskaya, L.L., Trevanion, S.J., Driscoll, S., Foyer, C.H., and Noctor, G., How does photorespiration modulate leaf amino acid contents? A dual approach through modelling and metabolite analysis, Plant Cell Environ., 2002, vol. 25, pp. 821–835.
Tarchevskii, I.A., Relationship between photosynthetic phosphorilation and assimilation of CO2 and other functions of chloroplasts and photosynthetic cells, in Biokhimiya i biofizika fotosinteza (Biochemistry and Biophysics of Photosynthesis), Krasnovskii, A.A., Ed., Moscow: Nauka, 1965, pp. 305–319.
Tarchevskii, I.A., Kurmaeva, S.A., and Vdovina, A.I., Change the direction of photosynthesis in plants transplanted under the forest canopy, Sov. Plant Physiol., 1962, vol. 47, pp. 1366–1368.
Chikov, V.I. and Nikolaev, B.A., The effect of drought on post-photosynthetic conversion of 14C in bean leaves, Sov. Plant Physiol., 1975, vol. 4, pp. 587–590.
Chikov, V.I., Evolution of notions about relationships between photosynthesis and plant productivity, Russ. J. Plant Physiol., 2008, vol. 55, pp. 130–148.
Karpilov, Yu.S. and Nedopekina, I.F., The products of photosynthesis in tomato and their effect on the formation of nitrogen–phosphorus nutrition, Tr. Moldav. Nauch. Issled. Inst. Oroshaemogo Zemledeliya Ovoshchevodstva., 1965, pp. 35–43.
Chikov, V.I., Fotosintez i transport assimilyatov (Photosynthesis and Transport of Assimilates), Moscow: Nauka, 1987.
Chikov, V.I. and Batasheva, S.N., The role of C to N balance in the regulation of photosynthetic function, in Advances in Photosynthesis–Fundamental Aspects, Najafpour, M.M., Ed., InTech., 2012, pp. 273–298. doi 10.5772/28084
Chikov, V. and Bakirova, G., Relationship between carbon and nitrogen metabolisms in photosynthesis. the role of photooxidation processes, Photosynthetica., 1999, vol. 37, p. 519.
Chikov, V.I., Bakirova, G.G., Avvakumova, N.Y., Belova, L.A., and Zaripova, L.M., Apoplastic transport of 14C photosynthates measured under drought and nitrogen supply, Biol. Plant., 2001, vol. 44, pp. 517–521.
Chikov, V.I., Akhtyamova, G.A., Batasheva, S.N., Mikhailov, A.L., Khamidullina, L.A., and Timofeeva, O.A., Effect of silencing of the apoplastic invertase gene on photosynthesis in tomato, Russ. J. Plant Physiol., 2015, vol. 62, pp. 39–44.
Gulyaev, B.I., Reaction of stomata to changes in the intensity of light and CO2 concentration, Fiziol. Biokh. Kul’t. Rast., 1979, vol. 11, no. 6, pp. 593–600.
Lu, P., Outlaw, W.H., Smith, B.G., and Freed, G.A., A new mechanism for the regulation of stomatal aperture size in intact leaves, Plant Physiol., 1997, vol. 11, pp. 109–118.
Outlaw, W.H., and Vlieghere-He, X.D., Transpiration rate. An important factor controlling the sucrose content of the guard cell apoplast of broad bean, Plant Physiol.., 2001, vol. 126, pp. 1716–1724.
Mokronosov, A.T., Ontogeneticheskii aspekt fotosinteza (Ontogenetic Aspects of Photosynthesis), Moscow: Nauka, 1981.
Kursanov, A.L., Transport assimilyatov v rastenii (Transport of Assimilates in Plants), Moscow: Nauka, 1976.
Chikov, V.I., Photorespiration, Soros. Obraz. Zh., 1996, no. 11, pp. 2–8.
Dutilleul, C., Lelarge, C., Prioul, J.-L., de Paepe, R., Foyer, C., and Noctor, G., Mitochondria-driven changes in leaf and status exert crutial influence on the control of nitrate assimilation and the integration of carbon and nitrogen metabolism, Plant Physiol., 2005, vol. 139, pp. 64–78.
Turgeon, R., Symplastic phloem loading and the sink–source transition in leaves: a model, in Recent Advances in Phloem Transport and Assimilate Compartmentation, Bonnemain, J.L., et al., Eds., Nant: Quest, 1991, pp. 18–22.
Taji, N., Ohsumi, C., Iuchi, S., Seki, M., Kasuga, M., Kobayashi, M., Yamaguchi, K., and Shinozaki, K., Important roles of droughtand cold-inducible genes for galactinol synthase in stress tolerance in Arabidopsis thaliana, Plant J., 2002, vol. 29, pp. 417–423.
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Original Russian Text–V.I. Chikov, A.L. Mikhailov, O.A. Timofeeva, L.A. Khamidullina, 2016, published in Fiziologiya Rastenii, 2016, Vol. 63, No. 1, pp. 76–82.
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Chikov, V.I., Mikhailov, A.L., Timofeeva, O.A. et al. Photosynthetic carbon metabolism in potato leaves under changes in light intensity. Russ J Plant Physiol 63, 70–76 (2016). https://doi.org/10.1134/S1021443716010040
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DOI: https://doi.org/10.1134/S1021443716010040