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Evaluation of Photosynthetic Behaviors by Simultaneous Measurements of Leaf Reflectance and Chlorophyll Fluorescence Analyses
Published on: August 9, 2019
Performance of the Photosynthetic Apparatus under Glass with a Luminophore Modifying Red-To-Far-Red-Light Ratio-A
Krzysztof M Tokarz1, Wojciech Makowski1, Barbara Tokarz1
1Department of Botany, Physiology and Plant Protection, University of Agriculture in Krakow, al. 29 Listopada 54, 31-425 Kraków, Poland.
Abstract:
The aim of this study was to examine the effect of the modified light spectrum of glass containing red luminophore on the performance of the photosynthetic apparatus of two types of lettuce cultivated in soil in a greenhouse. Butterhead and iceberg lettuce were cultivated in two types of greenhouses: (1) covered with transparent glass (control) and (2) covered with glass containing red luminophore (red). After 4 weeks of culture, structural and functional changes in the photosynthetic apparatus were examined. The presented study indicated that the red luminophore used changed the sunlight spectrum, providing an adequate blue:red light ratio, while decreasing the red:far-red radiation ratio. In such light conditions, changes in the efficiency parameters of the photosynthetic apparatus, modifications in the chloroplast ultrastructure, and altered proportions of structural proteins forming the photosynthetic apparatus were observed. These changes led to a decrease of CO2 carboxylation efficiency in both examined lettuce types.
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