Document Type: Research paper

Authors

1 Department of Dryland crop and horticultural science, college of dryland agriculture and natural resources, Mekelle University, Mekelle, Ethiopia

2 Department of plant and horticultural science, college of agriculture, Hawassa University, Hawassa, Ethiopia

Abstract

UV-B radiation and EOD light (EOD) quality has both signaling and damaging effects based on the dosage and time of exposure. At highland areas UV-B decreases crop productivity and also light quality increase at high elevation area but EOD light quality effect was not researched based on altitude. Therefore, in the present study a field experiment was conducted to investigate the effects of UV-B radiation, EOD light and its exclusion on growth performance and biomass accumulation of sweet potato cultivars on different altitude. The treatments consisting of UV-B exclusion, UV-B+ EOD light exclusion, + UV-B and (control) were studied on two sweet potato cultivars, Kulfo and Hawassa-83. The experimental design was laid out in split plot design with factorial combinations. According to the result, the highest UV-B radiation (1693.0 mw m-2 s-2) was recorded at highlands and the lowest (1107.1 mw m-2 s-2) was recorded at lowland areas. Also EOD light quality was low at lowland. Cultivar and altitude significantly affected growth and net assimilation rate but exclusion only affected growth rate. On dry weight accumulation, cultivar and altitude had high impact but exclusion affected tuber and specific leaf dry weight. Exclusion by cultivar interaction affected net-assimilation rate and specific leaf dry weight but exclusion by altitude interactions affected growth rate, net-assimilation rate and tuber dry weight. Altitude by cultivar doesn’t have any significant effect on growth performance but it has considerable effect on dry biomass accumulation. In conclusion, high UV-B at highland and low EOD time light quality at lowland negatively influenced growth performance and biomass of sweet potato cultivars

Keywords

1. Avery, L. M.; P. C. Thorpe, K. Thompson, N. D. Paul, J. P. Grime and H. M. West. 2004. Physical disturbance of upland grassland influences the impact of elevated UV-B radiation on metabolic profiles of below-ground micro-organisms. Global Change Biology 10: 1146–1154.
2. Agrawal S.B. 1992. Effects of supplemental UV-B radiation on photosynthetic pigment, protein and glutathione contents in green algae. Environmental and Experimental Botany 32(2): 137-143.
3. Albert, K.R, Mikkeleson, T.N, Poulsen .H, Andel M.F, Berdahl. L, Hakasson K.B, Boesgoared. K, and schmidet N.M, 2008. Improved UV-B screening capacit doesn’t present negative effects of Ambient UV Irradiance on PSǁ performance in high Arctic plants. Result from 6 year UV-B exclusion study. Journal of plant physiology. 167, 1542-1549.
4. Baker NP, Nogues S, Allen DJ. 1997. Photosynthesis and photo inhibition. In Lumsden P (ed.). Plants and UV-B: Responses to environmental change, Cambridge University Press pp 95-111.
5. Bjorn L.O .1996. Effect of ozone depletion and increased UV-B on terrestrial ecosystems. International Journal of Environmental 51: 217-243.
6. Blom, T. &Ingratta, F. 1983. The effect of high pressure sodium lighting on the production of tomatoes, cucumbers and roses. III International Symposium on Energy in Protected Cultivation, 148. 905-914.
7. Caldwell MM, Bjorn LO, Bornman JF, Flint SD, Kulandaivelu G, Terramara AH, Tevini M.1983.Effects of increased solar ultraviolet radiation on terrestrial ecosystems. Journal of Photochemistry and Biotechnology 46: 40-52.
10 Int. J. Hort. Sci. Technol; Vol. 7, No. 1; March 2020
8. Caldwell MM, Flint S D .1994. Stratospheric ozone reduction, solar UV-B radiation and terrestrial ecosystems. Climate Change, 28: 375–394
9. Caldwell MM.1971.Solar ultraviolet radiation as an ecological factor for alpine plants. Ecological Monographs, 38: 243–68.
10. Caldwell MM, Bjorn LO, Bornman JF, Flint SD, Kulandaivelu G, Terramara AH, Tevini M.1980.Effects of increased solar ultraviolet radiation on terrestrial ecosystems. Journal of Photochemistry and Biotechnology 46: 40-52.
11. Caldwell M M, Bjorn L O, Bornman J F, Flint S D, Kulandaivelu G, Teramura A H, Tevini M.1998.Effects of increased solar ultraviolet radiation on terrestrial ecosystems. Journal of Photochemistry & Photobiology B: Biology, 46: 40–52
12. Caldwell M M, Flint S D.1997.Uses of biological spectral weighting functions and the need for scaling for the ozone reduction problem. Plant Ecology, 128: 66–76
13. Coleman R.S, Day T.A .2004. Response of cotton and sorghum to several levels of sub ambient solar UV-B radiation: a test of the saturation hypothesis. Physiologia Plantarum, 122: 362–372.
14. Dai Q, Coronel V.P, Vergara BS, Barnes PW, Quintos. 1997. Ultraviolet-B radiation effects on growth and physiology of four rice cultivars. Crop Science, 32:1269-1274
15. Geo W, Zheng Y, Slusser JR, Heisler GM, Grant RH, Xu J, and He D. 2004. Effects ofsupplementary Ultraviolet-B radiation on maize yield and qualities: A field experiment. Journal of Photochemistry and Biotechnology 80: 127 – 131
16. Helsper, J.P., Ric de Vos, C.H., Maas, F.M., Jonker, H.H., Van Den Broeck, H.C., Jordi, W., Pot, C.S., Keizer, L.P. and Schapendonk, A.H., 2003. Response of selected antioxidants and pigments in tissues of Rosa hybrida and Fuchsia hybrida to supplemental UV‐A exposure. Physiologia Plantarum, 117(2), pp.171-178.
17. Hollosy. F.2002. Effects of ultraviolet radiation on plant cells. Micron 33. 179-197
18. Kakani, V.G., Reddy, K.R., Zhao, D. and Sailaja, K., 2003. Field crop responses to Ultraviolet-B radiation: a review. Agricultural and forest meteorology, 120(1-4), pp.191-218.
19. Kovacs, E. and Keresztes, A. (2002) Effect of Gamma and UV-B/C Radiation on Plant Cell.
Micron, 33, 199-210.
20. Kataria. S, Guruprasad K.N, Ahuja. S, Singh. B 2013. Enhancements of growth, photosynthetic performance and yield by exclusion of Ambient UV-B Components in C-3 and C-4 plants. Journal of photochemistry and photobiology 127, 140-152
21. Mazza C.A, Battissta. D, Zima A.M, Scwcrberg .M, Giordano .C, Aceveo. A, Ballare C. L 1999. The effects of Solar Ultraviolet B Radiation on growth and yield of Barely are accompanied by increased DNA damage and Antioxidant response. Plant cell environment 22, 61-70.
22. McKenzie, R.L., Björn, L.O., Bais, A. and Ilyasd, M., 2003. Changes in biologically active ultraviolet radiation reaching the Earth's surface. Photochemical & Photobiological Sciences 2(1), pp.5-15.
23. Nogués, S., Allen, D.J., Morison, J. I., and Baker,N.R. 1998. Ultraviolet-B radiation effects on water relations, leaf development and photosynthesis in drought Pea Plants. Plant Physiology, 117, 173-181.doi:10.1104/pp.117.1.173
24. Olszyk, D, Dai QJ, Teng P, Leung H, Luo Y, and Peng SB.1996. UV-B effects on crops: Response of irrigated rice ecosystem. J. Plant Physiol. 148: 26 – 34
25. Pal. M, Sherma .A, Abrol Y.P, Sengupta U.K . 1998.Exclusion of UV-B Radiations from Normal spectrum on growth of Mung bean and Maize. Ecosystem environment. 61, 29-34.
26. Pal .M, Zaidi P.H, Voleti S.R, and Raj. A 2016. Solar UV-B exclusion effect on Growth and photosynthetic characteristics of wheat and pea. Journal of New seeds.19-34.
27. Pfeifer, M.T., Koepke, P. and Reuder, J. 2006. Effects of altitude and aerosol on UV radiation. Journal of Geophysical Research: Atmospheres, 111(D1).
28. Robson, M. T., Klem, K., Urban, O. and Jansen, M. A. K. 2014. Re-interpreting plant morphological responses to UV-B radiation. Plant,Cell and Environment. Plant, cell & environment, 38(5), pp.856-866.
29. schumaker MM, Bassman JH, Robberecht R, Radamaker GK. 1997. Growth, leaf anatomy, and physiology of Populus clones in response to solar ultraviolet radiation. Tree Physiology (17), pp. 617– 626.
30. Sullivan, J.H., Teramura, A.H., Ziska, L.H.,1992. Variation in UV-B sensitivity of
Effect of solar ultraviolet-b radiation plus end of day light … 11
plants from 3000 m elevation gradient in Hawawi, American Journal of Botany, 737-743.
31. Sharma, R., 2001. Impact of solar UV-B on tropical ecosystems and agriculture. Case study: effect of UV-B on rice. Proceedings of SEAWIT98 and SEAWPIT2000, 1, pp.92-101.
32. Teshome, A., Nigussie, D. and Yibekal, A. 2012.Sweet potato growth parameters as affected by farmyard manure and phosphorus application at Adami Tulu, Central Rift Valley of Ethiopia. Agricultural science research journal, vol. 2(1), pp. 1 – 12
33. Xiong, F. S. and T. A. Day. 2001. Effect of solar Ultraviolet-B radiation during springtime ozone depletion on photosynthesis and biomass
production of Antarctic vascular plants. Plant Physiology, 125(2), pp.738-751.
34. Zeleke,G.,2010.A study on mountain externalities in Ethiopia. Sustainable Agriculture and Rural Development, Mountain Policy Project (AddisAbaba, Ethiopia).
35. Zhao-Go, Reddy KR, Kakani VG, Read JJ, Sullivan JH 2003. Growth and physiological responses of cotton (Gossypium hirsutum) to elevated carbon dioxide and Ultraviolet-B radiation under controlled environment conditions. Plants, Cell and Environment 26: 771–782.
36. Zuk-Golaszewska, K., Upadhyaya, M. and Golaszewski, J. 2004.The effect of UV-B radiation on plant growth and development. Plant soil and environment, 49 (3): 135-140.