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\hypersetup{pdftitle={Growth and Quality of Sugar Beet (\textit{Beta vulgaris} L) Growing under Colored Covers  in Duitama - Colombia},pdfauthor={Fánor Casierra Posada, Rogelio Pinto, Carlos Berdugo, Jaime  Peña-Olmos},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Cryptochrome, growth analysis, light intensity, light quality, phytochrome, Brix},pdfpagemode=None,colorlinks=true}
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\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 14-16, 2010, Zurich}}\\[1ex] \Large{``World Food System  ---\\A Contribution from Europe''\\[2ex]}}
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\begin{center}
\Large{\textbf{Growth and Quality of Sugar Beet (\textit{Beta vulgaris} L) Growing under Colored Covers  in Duitama - Colombia\footnote{\textbf{Contact Address:} Fánor Casierra Posada, Pedagogical and Technological University of Colombia, Faculty of Agricultural Sciences - Plant Ecophysiology Group, Carretera Central del Norte km 1 Vía a Paipa, Tunja, Colombia, \mbox{e-mail}: \email{fanor.casierra@uptc.edu.co}}\\[0.8ex]}}
\normalsize{\textsc{Fánor Casierra Posada$^{1}$, Rogelio Pinto$^{1}$, Carlos Berdugo$^{2}$, Jaime  Peña-Olmos$^{1}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Pedagogical and Technological University of Colombia, Faculty of Agricultural Sciences, Colombia}}}
\item[]{\small{\textit{$^{2}$University of Bonn, ARTS International Master Programm, Germany}}}
\end{itemize*}
\index[author]{Casierra Posada, Fánor}
\index[author]{Pinto, Rogelio}
\index[author]{Berdugo, Carlos}
\index[author]{Peña-Olmos, Jaime }
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Light is the all"=important source of energy used by plants in photosynthesis. But light is not just one simple, well"=defined entity. The plant response is influenced by light quality (colour), intensity and duration. Different colour of the incident light influences many vital processes in photosynthetic organisms. It differently affects growth and productivity of plants. Growth and quality of sugar beet plants (\textit{Beta vulgaris} L. var. Crosby egipcia) growing on field under transparent, red and blue coloured films were evaluated in Duitama / Colombia. Control plants grew without cover. The red colour promoted the growth of plants, expressed as an increase in leaf area and total dry weight per plant. The blue colour produced an opposite effect. While the leaf area was increased \mbox{22.2\,\%} in plants under red cover, for plants placed under the blue cover it decreased \mbox{15.2\,\%} in relation to control plants. In terms of dry weight per plant, this was increased \mbox{21.1\,\%} under the red cover and fell \mbox{29.0\,\%} under the blue compared with control. A similar trend as growth occurred by the quality of the roots. The total soluble solids content increased \mbox{7.7\,\%} under the red cover and decreased \mbox{13.7\,\%} under the blue. The diameter and root fresh weight showed the same trend. The transparent cover had no effect on the evaluated parameters, except on the root diameter. Although transparent, red and blue covers reduced \mbox{25.9\,\%}, \mbox{73.8\,\%} and \mbox{83.7\,\%} illuminance, respectively; the red coloured cover improved values of variables related to plants growth and root quality. The colour of light (red and blue) had a significant effect on the growth and quality of sugar beet. This effect decreased in the order red$>$transparent$>$blue. Results suggest that the phytotechnical advantage presented by the red cover was due to the alteration on the spectral properties. Differences in the total amount of radiation transmitted itself and differences in thermic transmissivities had not impact on the plant growth. }

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\noindent \textbf{Keywords:} Cryptochrome, growth analysis, light intensity, light quality, phytochrome, Brix
\index[key]{Cryptochrome}
\index[key]{Growth!analysis}
\index[key]{Light intensity}
\index[key]{Light quality}
\index[key]{Phytochrome}
\end{document}