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597 601 Evtushenko, E. V., Chekurov, V. M. (2004): Inheritance of the light intensity response in spring cultivars of common wheat. Hereditas , 141 , 288

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Acta Biologica Hungarica
Authors: Ildikó Karsai, B. Kőszegi, G. Kovács, P. Szűcs, Klára Mészáros, Z. Bedő, and O. Veisz

the light intensity response in spring cultivars of common wheat. Hereditas 141 , 288–292. Chekurov V. M. Inheritance of the light intensity response in spring cultivars of

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650 Evtushenko, E. V., Chekurov, V. M. (2004): Inheritance of the light intensity response in spring cultivars of common wheat. Hereditas , 141 , 288

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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.

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Abstract  

It has been shown that simultaneous measurements of reflected light intensity (RLI) with DSC can give additional and valuable information for the thermal analysis of materials including pure organic and inorganic chemicals, natural and synthetic polymers and foods. This paper extends the range of polymers studied and examines the possibility of improving the reproducibility and quantitative nature of RLI measurements. Polymer crystallisation, the curing of epoxy resins, the action of fire retardant additives and the degradation of polymers and proteins are among the systems studied.

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Cereal Research Communications
Authors: E. Skrzypek, M. Warchoł, I. Czyczyło-Mysza, I. Marcińska, A. Nowakowska, K. Dziurka, K. Juzoń, and A. Noga

Oat haploid embryos were obtained by wide crossing with maize. The effect of light intensity during the growing period of donor plants (450 and 800 µmol m−2 s−1) and in vitro cultures (20, 40, 70 and 110 µmol m−2 s−1) was examined for the induction and development of oat DH lines. Oat florets (26008) from 32 genotypes were pollinated with maize and treated with 2,4-dichlorophenoxyacetic acid. All the tested genotypes formed more haploid embryos when donor plants were grown in a greenhouse (9.4%) compared to a growth chamber (6.1%). The light intensity of 110 µmol m−2 s−1 during in vitro culture resulted in the highest percentage of embryo germination (38.9%), conversion into plants (36.4%) and DH line production (9.2%) when compared with lower light intensities (20, 40 and 70 µmol m−2 s−1). The results show that the growth conditions of the donor plant and light intensity during in vitro culture can affect the development of haploid embryos. This fact may have an impact on oat breeding programs using oat × maize crosses.

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Journal of Thermal Analysis and Calorimetry
Authors: C. A. Gracia-Fernández, P. Davies, S. Gómez-Barreiro, Beceiro J. López, J. Tarrío-Saavedra, and R. Artiaga

constrained to 350–500 nm by insertion of an optical filter in the light path. The light intensity can be adjusted between 1 and 2000 mW cm −2 . Since the TMDSC instrument used in this work is furnished with the Tzero (tm) technology, it is possible to perform

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by computing the total light intensity. The latter may be calculated as the sum or average of the grey levels in all pixel (pixel value ranges from black = 0 to white = 255). As the image becomes brighter, the light intensity value becomes higher. The

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Wherley, B. G., Gardner, D. S., Metzger, J. D. (2005): Tall fescue photomorphogenesis as influenced by changes in the spectral composition and light intensity. Crop Sci. , 45 , 562–568. Metzger J. D

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The dormancy of potato microtubers produced under different photoperiodic treatments and light intensities was investigated in the varieties Desiree and Gülbaba. The dormant period was defined as the period between harvest or tuber initiation and the end of dormancy. The effects of environmental factors could be detected due to the use of a hormone-free tuber-producing system. Combined treatments had a slight effect on dormancy, while different light intensities influenced it considerably. The lower the light intensity the longer the dormant period for both cultivars. The effects of light intensities depended on the photoperiodic treatments applied for tuber induction.

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