Life Sciences Commons^™

Leaf Epidermal Transmittance Of Ultraviolet Radiation And Its Implication For Plant Sensitivity To Ultraviolet-Radiation Injury, Ronald Robberecht

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf epidermal transmittance of ultraviolet radiation (280-400 nm) was examined in several plant species to determine the capability of the epidermis to attenuate solar ultraviolet radiation. Epidermal samples were mechanically isolated and examined with a spectroradiometer/integrating sphere for transmittance. A survey of 25 species exposed to natural insolation was conducted. Although the species differed in life form, habitat type, and epidermal characteristics, epidermal transmittance was generally less than 10%. Ultraviolet radiation was attenuated 95 to 99% in more than half of the species. In 16 species, flavonoid and related pigments in the epidermis accounted for 20 to 57% of the …