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\hypersetup{pdftitle={Effect of Colored Films on Growth and Flower Quality of Callas (\textit{Zantedeschia aethiopica} L.) in the Andean Highlands - Colombia},pdfauthor={Fánor Casierra Posada, Paola J. Nieto, Carlos Berdugo},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Cryptochrome, cut flowers, growth analysis, light intensity, light quality, phytochrome},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{Effect of Colored Films on Growth and Flower Quality of Callas (\textit{Zantedeschia aethiopica} L.) in the Andean Highlands - 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$^{1}$, Paola J. Nieto$^{1}$, Carlos Berdugo$^{2}$}}
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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]{Nieto, Paola J.}
\index[author]{Berdugo, Carlos}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Callas (\textit{Zanthedeschia aethiopica}) is a dicotyledonous plant which belongs to the family Araceae. The crop is mainly used as cut flowers or potted plants for their attractive spathes, commonly refers to as flowers. For exportation, this plant is cultivated in Colombia under greenhouse conditions, since light intensity, temperature and relative humidity are variable factors under tropical conditions. This production system can alter the growth and production of patterns plants. The effect of white, red, blue, yellow and green coloured translucent films on growth and flower production and flower quality of \textit{Z. aethiopica} was studied in Tunja / Colombia. Plants were produced from tubers and grown in aerated nutrient solution. The coloured films were expanded \mbox{80\,cm} on plants. Control plants were not covered. 227 days after planting, plants were harvested and growth parameters were calculated. Flower quality was evaluated at harvest of each flower. Neither the time of appearance of the flower, or the number of flowers per plant were affected by the colour of the cover; however, the length of the peduncles was influenced by the covers due to the fact that an increase of \mbox{4.57\,\%}, \mbox{14.09\,\%}, \mbox{16.28\,\%} and \mbox{44.30\,\%} in relation to control was present under blue, yellow, red and green covers, respectively. The root to shoot ratio was reduced \mbox{54.03\,\%} and \mbox{59.6\,\%} under green and blue covers respectively. While the colours red, yellow and blue reduced \mbox{4.34\,\%}, \mbox{14.16\,\%} and \mbox{31.8\,\%} the production of dry matter per plant compared with control, and transparent green covers induced a increased it \mbox{4.34\,\%} and \mbox{9.54\,\%}. The leaf area was increased under green colour. Exposure of plants to blue light reduced the absolute and relative growth rates. It was possible to conclude that the management of the spectrum can modify the patterns of plant growth and flower commercial characteristics in Callas.}

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