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The Importance of Short-Term Ultraviolet-B Radiation in Biomass and Photosynthetic Productivity of Eichhornia Crassipes (Mart.) Solms

Authors Cong, Wei; Li, Xia

Journal JOURNAL OF PLANT GROWTH REGULATION , SEP 2018,3:37

DOI 10.1007/s00344-018-9785-z

Abstract The current study was designed to test the concerning strategy of water hyacinth (Eichhornia crassipes (Mart.) Solms) to UV-B. In this study, we evaluated the short-term effect of UV-B radiation (short-term UV-B radiation, S-UV-B) on water hyacinth under the natural conditions of Nanjing, China (118A degrees 46''E, 32A degrees 24''N, 30 m above sea level) with supplemental ultraviolet-B (12 W m(-2) above ambient). The growth characteristics and the photosynthetic performance of water hyacinth leaves exposed to UV-B were assessed by measuring net photosynthetic rate, the specific fluorescence parameters including maximal fluorescence (F (m)), efficiency of photosystem II (F (v)/F (m)), and JIP-test parameters. Water hyacinth was tolerant to 1-h UV-B doses over 25 days, maintaining a stable dry weight after treatment. Conversely, plants showed elongation of roots and a decrease in ramet numbers. These changes in growth were closely related to a physiological protection strategy consisting of a higher ability to dissipate extra light energy, strong antioxidative abilities, higher phosphoenolpyruvate carboxylase (PEPC) activity, and stable ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) activity, as indicated by the stable net photosynthetic rate and reduced inhibition of reactive oxygen species content. After the 3-h dose of UV-B, dry weight decreased significantly, as the above-mentioned protective strategy could not cope with the oxidative damage arising from these treatments. The study concludes that S-UV-B is a potent stimulating factor in increasing the concentrations of defense compounds and antioxidants in water hyacinth to optimize its performance under stress.

Species covered 凤眼蓝 Eichhornia crassipes