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\hypersetup{pdftitle={The Effect of Tillage Methods on Emergence and Distribution of Weeds in Cotton Followed by Rapeseed},pdfauthor={Naser Latifi, Asieh Siah-Marguee, Farshid Ghaderi-Far, Saeed Mahghani},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Cotton, Tillage Systems, 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{The Effect of Tillage Methods on Emergence and Distribution of Weeds in Cotton Followed by Rapeseed\footnote{\textbf{Contact Address:} Asieh Siah-Marguee, Islamic Azad University of Gorgan, Agronomy, Mashhad, Iran, \mbox{e-mail}: \email{siahmargue@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Naser Latifi$^{1}$, Asieh Siah-Marguee$^{2}$, Farshid Ghaderi-Far$^{3}$, Saeed Mahghani$^{4}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$Gorgan University, Agronomy, }}}
\item[]{\small{\textit{$^{2}$Islamic Azad University of Gorgan, Agronomy, Iran}}}
\item[]{\small{\textit{$^{3}$Gorgan University of Agricultural Science and Natural Resources, Dept. of Agronomy, Iran}}}
\item[]{\small{\textit{$^{4}$Graduate Student of Tabriz University, Agronomy, }}}
\end{itemize*}
\index[author]{Latifi, Naser}
\index[author]{Siah-Marguee, Asieh}
\index[author]{Ghaderi-Far, Farshid}
\index[author]{Mahghani, Saeed}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
 Study of tillage method and crop following effects on sustainable weed management are two important factors in agricultural systems. In order to study the effects of different tillage methods on variety and density of weeds on cotton followed by rapeseed, this research was conducted in complete block design in three replication in Gorgan in 2005.The treatments were different tillage methods such as no"=tillage (plant in cutting residue), plowing plus disk (as a common method), chisel plus disk (as low tillage) and two disk (as a minimum tillage). Weeds and rapeseed seedlings that germinated in cotton were counted three times (in two leaved, squaring and flowering stages of cotton) in each treatment. The results showed that weed density and weeds species were affected by tillage methods significantly. Perennial weeds specially Cyperus rotundus L. were more in no tillage treatment but annual weeds for example Physalis alkekengi L. , Solanum nigrum L. and Amaranthus spp. were more dominant in common tillage. In low tillage treatments (Chisel and Disk) there was both annual and perennial weeds .Germination of rapeseed in no"=tillage, plow, chisel and disk was more than common tillage. On view of yield, there was no significant difference between low tillage systems and common tillage, therefore we can use low tillage system instead of common tillage but we have to find benefit and proper methods for weed control in this system. More researches for investigation The effect of tillage methods on emergence and distribution of weeds in cotton followed by rapeseed are needed.}

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\noindent \textbf{Keywords:} Cotton, Tillage Systems, weeds
\index[key]{Cotton}
\index[key]{Tillage Systems}
\index[key]{Weeds}
\end{document}