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\hypersetup{pdftitle={Investigation of Species Diversity of Weed in Wheat Fields},pdfauthor={Maryam Jahani, Alireza Koocheki, Mehdi Nassiri-Mahalati, Golsoomeh Azizi, Asieh Siah-Marguee, Leila Alimoradi},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Shanon index, weed diversity, weeds},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{Investigation of Species Diversity of Weed in Wheat Fields\footnote{\textbf{Contact Address:} Maryam Jahani, Ferdowsi University of Mashhad, College of Agriculture, Department of Agronomy, Mashhad, Iran, \mbox{e-mail}: \email{mrkondori@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Maryam Jahani$^{1}$, Alireza Koocheki$^{2}$, Mehdi Nassiri-Mahalati$^{3}$, Golsoomeh Azizi$^{4}$, Asieh Siah-Marguee$^{5}$, Leila Alimoradi$^{6}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Ferdowsi University of Mashhad, College of Agriculture, Department of Agronomy, Iran}}}
\item[]{\small{\textit{$^{2}$Ferdowsi University of Mashhad, College of Agriculture, Department of Agronomy, Iran}}}
\item[]{\small{\textit{$^{3}$Ferdowsi University of Mashhad, Agronomy, }}}
\item[]{\small{\textit{$^{4}$Payam Noor University, Agronomy, Iran}}}
\item[]{\small{\textit{$^{5}$Islamic Azad University of Gorgan, Agronomy, Iran}}}
\item[]{\small{\textit{$^{6}$Islamic Azad University - Mashhad Branch, Department of Agronomy, Iran}}}
\end{itemize*}
\index[author]{Jahani, Maryam}
\index[author]{Koocheki, Alireza}
\index[author]{Nassiri-Mahalati, Mehdi}
\index[author]{Azizi, Golsoomeh}
\index[author]{Siah-Marguee, Asieh}
\index[author]{Alimoradi, Leila}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
In order to investigate diversity of weed species in wheat fields in ester parts of Mashhad, an investigation was made in the year 1388. Wheat fields was classified based on the acreage from 3--\mbox{5\,ha}, 5--\mbox{10\,ha} and higher than \mbox{10\,ha}. Sampling was made randomly by a quadrate 0.5* 0.5 in 9 fields of each group from jointing to heading of wheat in tow separate stages. Type and total number of weeds were recorded in each quadrate. The results showed that total number of weed species in first sampling were 20 from 10 different plant family and in second sampling 18 species from 8 plant families. In both sampling, number of dicotyledons species (30) were more than monocotyledons (8). The highest diversity in dicotyledon was observed for composite and cruciferae with 7 and 9 species respectively. For monocotyledons, gramineae family with 8 species showed the highest diversity. There was a negative relationship between the size of fields and shanon index. The highest shanon index in the first and the second sampling was observed (1.33 , 1.85) respectively with \mbox{2\,ha} area and the lowest shanon index  in the first sampling was observed with 30 and \mbox{20\,ha} (H´= 0) in the second sampling, these value were  0.46 and 0.5 for 30 and \mbox{20\,ha} respectively. In general, species richness and similarity index were low in the area. More researches for investigation of species diversity of weed in wheat fields and effect of these plants on yield of wheat are needed.







}

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\end{abstract}
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\noindent \textbf{Keywords:} Shanon index, weed diversity, weeds
\index[key]{Shanon index}
\index[key]{Weed diversity}
\index[key]{Weeds}
\end{document}