Epidermal UV‐A absorbance and whole‐leaf flavonoid composition in pea respond more to solar blue light than to solar UV radiation

• DOI: 10.1111/pce.12403
• Publication Date: 2014-07-08T09:15:04Z
• Authors: SARI M. SIIPOLA; TITTA KOTILAINEN; NINA SIPARI; LUIS O. MORALES; ANDERS V. LINDFORS; T. MATTHEW ROBSON; PEDRO J. APHALO
• Keywords: Absorbance; Ultraviolet; Photoprotection

Plants synthesize phenolic compounds in response to certain environmental signals or stresses. One large group of phenolics, flavonoids, is considered particularly responsive ultraviolet (UV) radiation. However, here we demonstrate that solar blue light stimulates flavonoid biosynthesis the absence UV-A and UV-B We grew pea plants (Pisum sativum cv. Meteor) outdoors, Finland during summer, under five types filters differing their spectral transmittance. These were used (1) attenuate UV-B; (2) < 370 nm; (3) UV-A; (4) UV-B, light; (5) as a control not attenuating these wavebands. Attenuation significantly reduced content leaf adaxial epidermis whole-leaf concentrations quercetin derivatives relative kaempferol derivatives. In contrast, responses significant. results show regulate epidermal absorbance accumulation individual flavonoids by perceiving complex radiation extend into visible region spectrum. Furthermore, instead can be main regulator compound germinate develop outdoors.