A baseline assessment of the photosynthetic potential of Welwitschia mirabilis using the JIP-test for monitoring and conservation purposes
Keywords:chlorophyll a fluorescence, JIP-test, photosynthesis, PIABS, Welwitschia mirabilis, Welwitschia Plains
Background: Welwitschia mirabilis is highly specialised to survive the harsh climate of the Namib Desert. Changes in land use, such as the expansion of mining activities, may endanger their survival.
Objectives: The purpose of this study was to understand the photosynthetic potential of W. mirabilis plants to provide a baseline for future long-term monitoring, and for future comparison to determine plant health status after the onset of mining operations.
Methods: The study was conducted in a population of W. mirabilis on the Welwitschia Plains. Chlorophyll a fluorescence data were used to measure plant photochemical potential and analysed using the JIP-test.
Results: Significant differences in the photosynthetic potential was observed for W. mirabilis plants located in different catchments. The partial parameters of the PIABS values were also significantly lower, which indicated that all aspects of photosynthesis were influenced.
Conclusion: PIABS values can serve as a baseline for future long-term monitoring studies to detect any changes in the health status of W. mirabilis that might result from land use change.
Busotti, F., Desotgiu, R., Pollastrini, M. & Cascio, C., 2010, ‘The JIP test: a tool to screen the capacity of plant adaptation to climate change’, Scandanavian Journal of Forest Research, 25(8), 43–50, https://doi.org/10.1080/02827581.2010.485777.
Chaerle, L. & Van Der Straeten, D., 2000, ‘Imaging techniques and the early detection of plant stress’, Trends in Plant Science, 5(11), 495–501, https://doi.org/10.1016/S1360-1385(00)01781-7.
Cooper-Driver, G., 1994, ‘Welwitschia mirabilis – a dream come true’, Arnoldia, 54(2), 2–10.
Henschel, J. & Seely, M.K., 2000, ‘Long-term growth patterns of Welwitschia mirabilis, as long-lived plant of the Namib Desert’, Plant Ecology, 150(1–2), 7–26, https://doi.org/10.1023/A:1026512608982.
Fan, J., Xu, Y., Ge, H. & Yang, W., 2020, ‘Vegetation growth variation in relation to topography in Horqin Sandy Land’, Ecological Indicators, 113, 106–215.
Humavindu, M. & Stage, J., 2013, ‘Key sectors of the Namibian economy’, Journal of Economic Structures, 2(1), 1–15, https://doi.org/10.1186/2193-2409-2-1.
Janssen, L.H. & Hasselt, P.R., 1994, ‘Temperature effects on chlorophyll fluorescence induction in tomato’, Journal of Plant Physiology, 144(2), 129–135.
Kalaji, H.M., Jajoo, A., Oukarroum, A., Brestic, M., Zivcak, M., Samborska, I.A. & Ladle, R.J., 2016, ‘Chlorophyll a fluorescence as a tool to monitor physiological status of plants under abiotic stress conditions’, Acta Physiologiae Plantarum, 38(4), 102, https://doi.org/10.1007/s11738-016-2113-y.
Mikita, T. & Klimánek, M., 2010, ‘Topographic exposure and its practical applications’, Jounal of Landscape Ecology, 3(1), 42–51.
Schulze, E.D., Ziegler, H. & Stichler, W., 1976, ‘Environmental control of Crassulacean Acid Metabolism in Welwitschia mirabilis Hook. Fil. in in its range of natural distribution in the Namib desert’, Oecologia, 24, 323–334.
Shanyengana, E.S., Henschel, J.R., Seely, M.K. & Sanderson, R.D., 2002, ‘Exploring fog as a supplementary water source in Namibia’, Atmospheric Research, 64(1), 251–259, DOI:10.1016/S0169-8095(02)00096-0.
Stirbet, A., 2011, ‘On the relation between the Kautsky effect (chlorophyll a fluorescence induction) and photosystem II: Basic applications of the OJIP fluorescent transient’, Journal of Photochemistry & Photobiology B: Biology, 104, 236–257, DOI:10.1016/j.jphotobiol.2010.12.010.
Strasser, R.J., Srivastava, A. & Tsimilli-Michael, M., 2000, ‘The fluorescence transient as a tool to characterize and screen photosynthetic samples’, in M. Yunus, U. Pathre & P. Mohanty (eds), Probing photosynthesis: Mechanisms, regulation and adaptation, London: Taylor & Francis, pp. 445–483.
Strasser, R.J., Tsimilli-Michael, M. & Srivastava, A., 2004, ‘Analysis of the chlorophyll a Fluorescence Transient’, in G.C. Papageorgiou & Govindjee (eds), Chlorophyll a fluorescence. A signature of photosynthesis. Advances in Photosynthesis and Respiration, vol 19. Dordrecht: Springer, p. 818.
Tsimilli-Michael, M. & Strasser, R.J., 2008, ‘In vivo assessment of stress impact on plant’s vitality: applications in detecting and evaluating the beneficial role of mycorrhization on host plants’, in A. Varma (ed.), Mycorrhiza. Berlin: Springer.
Veste, M. & Herppich, W.B., 2008, ‘Welwitschia mirabilis – Eine ökophysiologische Betrachtung’, Naturwissenschaftliche Rundschau, 61, 620–624.
von Willert, D.J., Armbrüster, N., Drees, T. & Zaborowski, M., 2005, ‘Welwitschia mirabilis: CAM or not CAM – what is the answer?’, Functional Plant Biology, 32(5), 389–395, DOI: 10.1071/FP01241.
World Heritage Convention, 2002. Welwitschia plains. Available at: http://whc.unesco.org/en/tentativelists/1747/ (Accessed: 9 September 2015).
How to Cite
Copyright (c) 2021 Creative Commons Attribution 4.0 International license (CC BY 4.0)
This work is licensed under a Creative Commons Attribution 4.0 International License.