Authors:Henryk Dębski, Magdalena Szwed, WiesŁaw Wiczkowski, Dorota Szawara-Nowak, Natalia Bączek, and Marcin Horbowicz
Horbowicz , M. , Wiczkowski , W. , Koczkodaj , D. , Saniewski , M. ( 2011 ) Effects of methyl jasmonate on accumulation of flavonoids in seedlings of commonbuckwheat (Fagopyrum esculentum Moench) . Acta Biol. Hung. 62 , 265 – 278
Authors:H. Dębski, W. Wiczkowski, D. Szawara-Nowak, N. Bączek, M. Szwed, and M. Horbowicz
The effects of two light intensities on the concentration of several flavonoids were investigated in the cotyledons of common buckwheat seedlings. The study was performed on four days old seedlings of cvs. Hruszowska, Panda, Kora and Red Corolla. One group of seedlings was grown under exposure to 180 ± 20 μmol · m−2 · s−1 photosynthetically active radiation, whereas the other group was exposed to 360 ± 20 μmol · m−2 · s−1. The experiment lasted 5 days. The results revealed that light intensity induces changes in the levels of flavonols and flavones. Increased light intensity contributed to a decrease in the concentrations of all flavone C-glucosides: orientin (luteolin-8-C-glucoside) and iso-orientin (luteolin-6-C-glucoside), and apigenin: vitexin (apigenin-8-C-glucoside) and iso-vitexin (apigenin-6-C-glucoside). Simultaneously, a substantial increase in the content of flavonols, i.e. quercetin O-glycosides, was found. To the best of our knowledge, this is the first evidence to demonstrate the contrary responses of plant flavonols and flavones to light intensity. The content of anthocyanin also increased under exposure to higher light intensity. Our results indicate that quercetin O-glycosides can play a similar role to anthocyanins in the cotyledons of common buckwheat seedlings. Results of correlation analysis indicate that the increase in flavonol and anthocyanin concentrations in response to higher light intensity is maintained through reduced accumulation of flavones and proanthocyanidins.
Authors:M. Germ, B. Breznik, N. Dolinar, I. Kreft, and A. Gaberščik
The effects of elevated UV-B radiation and water limitation have been evaluated in terms of the biochemical, physiological, morphological and productivity responses of common buckwheat (Fagopyrum esculentum Moench) and tartary buckwheat (Fagopyrum tataricum Gaertn.). Research was carried out under semi-controlled conditions. Common and tartary buckwheat were exposed to UV-B radiation and water limitation in different combinations. Photosynthetic pigments, UV-absorbing compounds, potential and effective photochemical efficiency, stomatal conductance, plant morphology and biomass production were monitored. The negative effect of elevated UV-B radiation on growth parameters in common buckwheat was highly significant in watered plants but less pronounced in plants exposed to water limitation. However, in tartary buckwheat UV-B radiation mitigated the negative effects of water limitation, resulting in increased biomass production.