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\hypersetup{pdftitle={Leaf Area Index and Measurements of Light Transmission as Management Tools for Banana Production in Central American Coffee Agroforestry Systems},pdfauthor={Maria Alejandra Arias Escobar, Charles Staver, Pablo Siles, Oscar Bustamante, Paulo Dos Santos Faria Lichtemberg, Luis Pocasangre, Jürgen Burkhardt},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Dry matter, musa, shade},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{Leaf Area Index and Measurements of Light Transmission as Management Tools for Banana Production in Central American Coffee Agroforestry Systems\footnote{\textbf{Contact Address:} Maria Alejandra Arias Escobar, University of Bonn, ARTS, 53115~Bonn, Germany, \mbox{e-mail}: \email{marialejandrarias@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Maria Alejandra Arias Escobar$^{1}$, Charles Staver$^{2}$, Pablo Siles$^{3}$, Oscar Bustamante$^{4}$, Paulo Dos Santos Faria Lichtemberg$^{5}$, Luis Pocasangre$^{6}$, Jürgen Burk\-hardt$^{7}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$University of Bonn, ARTS, Germany}}}
\item[]{\small{\textit{$^{2}$CGIAR, Bioversity International, France}}}
\item[]{\small{\textit{$^{3}$Bioversity International, }}}
\item[]{\small{\textit{$^{4}$Bioversity International, Costa Rica}}}
\item[]{\small{\textit{$^{5}$University of Bonn, Phytopathology and Nematology in Soil Ecosystems, Institute for Crop Science and Resource Conservation, Germany}}}
\item[]{\small{\textit{$^{6}$Bioversity International, Costa Rica}}}
\item[]{\small{\textit{$^{7}$University of Bonn, Institute of Crop Science and Resource Conservation - Plant Nutrition, Germany}}}
\end{itemize*}
\index[author]{Arias Escobar, Maria Alejandra}
\index[author]{Staver, Charles}
\index[author]{Siles, Pablo}
\index[author]{Bustamante, Oscar}
\index[author]{Lichtemberg, Paulo Dos Santos Faria}
\index[author]{Pocasangre, Luis}
\index[author]{Burk\-hardt, Jürgen}
\begin{center}
\vspace{1.1cm}
\textbf{Abstract}
\begin{abstract}
\normalsize{
Sixty smallholders intercropping coffee, banana (Musa spp.) and trees in Costa Rica and Nicaragua were described, of which twenty farms were intensively investigated. The aim was to identify promising management tools which may help to improve banana production; this was based on the assumption that bananas have to face deep"=shaded conditions, and that coffee, banana, and trees may influence each other. 



As a result to this assumption, interrelationships between Leaf Area Index (LAI), above ground dry matter, percent"=intercepted incident radiation, and banana production were evaluated. Transmitted radiation was estimated with hemispherical photography. Leaf area and dry matter of banana were partly estimated with non"=destructive methods.



Linear regression analysis between destructive leaf area and non"=destructive leaf area estimation was conducted, with an equation promoted by Turner (2003), is promising in the field (R$^2$ = 0.96). A linear regression between above ground dry matter and circumference may allow dry matter estimation (R$^2$ = 0.84). 



Thirteen different banana cultivars were identified; most common are AAA `Gros Michel' and AAA `Cavendish' cultivars. Mean LAI is 0.5 at plant density of 349 banana ha$^{-1}$. Mean percent transmitted light was \mbox{45\,\%} at 300--\mbox{340\,cm} height and decreased to \mbox{28\,\%} in \mbox{90\,cm} height. LAI and dry matter seem to increase with percent intercepted light which may indicate that light is a limiting factor in the system. Tree canopy area and tree crown surface are significantly negative linear, correlated to percent intercepted light of banana. There is a linear interrelationship between LAI and above ground dry matter of banana on farm level (R$^2$=0.95; linear regression). Dry matter is weakly correlated to number of hands per banana bunch which could be the link between LAI, intercepted light and banana production. Further research should focus on optimum LAI of banana in coffee agroforestry systems, and light response of promising banana cultivars.



}

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\noindent \textbf{Keywords:} Dry matter, musa, shade
\index[key]{Dry matter}
\index[key]{Musa}
\index[key]{Shade}
\end{document}