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\hypersetup{pdftitle={Using Polyculture for Combating Desertification in Egypt.  Case Study},pdfauthor={Hussein Abouziena, Elham Abd-Elmotty, Ahmad Farahat Sahab},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Biodiversity, date palm, mandarin, mango, polyculture},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{Using Polyculture for Combating Desertification in Egypt.  Case Study\footnote{\textbf{Contact Address:} Hussein Abouziena, National Research Center, Botany, Elbhoss Street, 12622~Dokki, Egypt, \mbox{e-mail}: \email{abouzainah@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Hussein Abouziena$^{1}$, Elham Abd-Elmotty$^{2}$, Ahmad Farahat Sahab$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$National Research Center, Botany, Egypt}}}
\item[]{\small{\textit{$^{2}$National Research Center, Pomology Res., }}}
\item[]{\small{\textit{$^{3}$National Research Center, Plant Pathology, }}}
\end{itemize*}
\index[author]{Abouziena, Hussein}
\index[author]{Abd-Elmotty, Elham}
\index[author]{Sahab, Ahmad Farahat}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Desertification is a worldwide problem that directly affects over 250 million people and a third of the earth's land surface. It is especially concentrated in developing countries. The recent report of Egypt indicated that \mbox{67.4\,\%} of the first class area of the land was reduced from 1.260 millions hectares (in the 2000) to 0.411 million hectares (in 2005). Combating Desertification requires an integrated approach. Polyculture is claimed to be one of the most significant cropping techniques in sustainable agriculture, to its utilisation a number of environmental benefits, from promoting land biodiversity to diversifying agricultural outcome. This model integrates low, medium, and tall plants, as well as plants of short, medium, and long life cycles, including trees. Therefore, a study was carried out to evaluate the impact of intercropping mango (\textit{Mangifera indica} L.), Balady mandarin (Citrus reticulate Blanco) and Egyptian clover (Trifolium alexandrinum L) crops in comparison with date palm sole. The effect of polyculture on occurrence and enumeration of microorganisms in the rhizosphere of trees was also studied. The results indicated that the colony count of fungi and bacteria in date palm rhizosphere were fluctuated according to plantation method. Intercropping date palm with mandarin decreased the total fungal count from 21.17 cfu\,$\times$\,103g$^{-1}$  in the non- intercropped roots to 16.00 cfu\,$\times$\,103g$^{-1}$ ( \mbox{24.4\,\%} decrease) in date palm root intercropped with mandarin. While, intercropping date palm with mango and clover increased the total fungal count to 118.32 cfu\,$\times$\,103g$^{-1}$ and 52.00\,$\times$\,103g$^{-1}$ in date palm root intercropped with mango and clover, respectively.  Growing mango or mandarin under date palm resulted in the highest fruit yield/palm. However, intercropping Egyptian clover with date palm caused a significant reduction in fruit diameter. Intercropping mango gave the highest net profit (\$8213/ha/yr), followed by the same area intercropped with mandarin (\$3992/ha/yr). Evaluation of growing mango, mandarin or Egyptian clover with date palm indicated that growing mango with date palm could be used for combating desertification in sandy soil in arid lands regions. }

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\end{abstract}
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\noindent \textbf{Keywords:} Biodiversity, date palm, mandarin, mango, polyculture
\index[key]{Biodiversity}
\index[key]{Date palm}
\index[key]{Mandarin}
\index[key]{Mango}
\index[key]{Polyculture}
\end{document}