Document Type : Original Article


1 Department of Dry Land Crop and Horticultural Science, College of Dry Land Agriculture and Natural Resources, Mekelle University, Mekelle, Ethiopia

2 Department of Plant and Horticultural Science, College of Agriculture, Hawassa University, Hawassa, Ethiopia


Purpose: herbaceous dicot plants mainly sweet potato is highly affected by UV-B and light quality based on altitude. Therefore, this study will give insights on the effect of UV-B and light quality on photosynthetic efficiency of sweet potato based on Altitude. Research method: The experimental design was laid out in split plot design with factorial arrangement. The treatments consist of +UV-B or control, UV-B exclusion, UV-B+end of day light exclusion, and the two sweet potato cultivars such as Kulfo and Hawassa-83. Main findings: highest UV-B (1693.0mw/m-2s-2) was recorded at highland (2230m.a.s.l) and the lowest (1107mw/m-2s-2) was recorded at lowland (1400m.a.s.l). The result shows that photosynthetic rate increased by 2.41% in Kulfo compared with Hawassa83 cultivar. Also altitude has a highly significant effect on photosynthetic efficiency; the highest stress level 0.68 and 0.72 was recorded at UV-B + EOD exclusion and highland. This indicate UV-B +EOD exclusion cause light quality and intensity stress at highland also UV-B was inducing high stress at highland area and affecting sweet potato productivity but exclusion increase Fv/Fm and stomata conductance it has no effect on photosynthesis and transpiration rate. Limitations: The research has a limitation due to Altitude difference it’s difficult to control factors other than UV-B and light Quality that may cause a difference. Originality/Value: This research tries to assess UV-B and end of day time light quality effects due to altitude difference and encourages new research on UV-B, its adaptation and light quality on crop productivity.


Main Subjects

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