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\hypersetup{pdftitle={Determination of Optimum Tapping Date for Gum Arabic Yield in the Nuba Mountain Area},pdfauthor={Idris Musa Adam, Kamal E. M. Fadl, Masuad Mohamed},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Gum Arabic, Sudan!South Kordofan, Acacia spp.},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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\Large{\textbf{Determination of Optimum Tapping Date for Gum Arabic Yield in the Nuba Mountain Area\footnote{\textbf{Contact Address:} Idris Musa Adam, Agricultural Research Corporation (ARC), Kadugli Research Station, Kadugli, 11111~Kadugli, Sudan, \mbox{e-mail}: \email{idrigand@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Idris Musa Adam$^{1}$, Kamal E. M. Fadl$^{2}$, Masuad Mohamed$^{3}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Agricultural Research Corporation (ARC), Kadugli Research Station, Sudan}}}
\item[]{\small{\textit{$^{2}$Agricultural Research Corporation (ARC), El Obeid Research Station, Sudan}}}
\item[]{\small{\textit{$^{3}$Forestry National Corporation (FNC), South Kordofan Office, Sudan}}}
\end{itemize*}
\index[author]{Adam, Idris Musa}
\index[author]{Fadl, Kamal E. M.}
\index[author]{Mohamed, Masuad}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
For more than two decades, the Nuba mountains area in South Kordofan State was under strife and civil war. During this period only few research efforts dealed with production of technologies in the area. Now due to the prevailing security situation in this State, proposing change and setting priorities is very important, and the fragile stability should strengthening the farmers. The objective of this study is to offer semi"=sustainable income to the land user by determination of the optimum tapping date for gum arabic production in the area.



A randomised complete block design experiment with three replications was conducted at (Meari) in Nuba mountain area for two seasons 2008/2009 -- 2009/2010. The treatments comprise 6 tapping dates for gum production of "Hashab'' tree \textit{Acacia senegal} (L.) Willd. This is from 1\textsuperscript{st} October till 15\textsuperscript{th} December with 15 days interval between each date and the other. 



The results of this analysis show highly significant differences between the tapping dates on gum yield in almost all pickings and for the total gum yield. It is evident that mid of October or 1\textsuperscript{st} November is the best and optimum tapping date for "Hashab'' tree in Nuba Mountains. By doing so farmer can originate about 8 pickings from "Hashab'' tree for gum arabic production in sequence of 15 days intervals in South Kordofan. This result can increase gum production in the area by \mbox{83\,\%} and tight the farmers to his land for a long time.



}

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\noindent \textbf{Keywords:} Gum Arabic, Sudan!South Kordofan, Acacia spp.
\index[key]{Gum Arabic}
\index[key]{Kadugli}
\index[key]{Nuba Mountains}
\index[key]{South Kordofan}
\index[key]{Acacia ssp.}
\end{document}