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\hypersetup{pdftitle={Comparison of Different Methods of Weed Control in Winter Canola (Brassica Napus L.)},pdfauthor={Hamid Reza Rajab Larijani, Majid Aghaalikhani},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Cultivation, herbicide, mulching, weed control, winter canola},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{Comparison of Different Methods of Weed Control in Winter Canola (Brassica Napus L.)\footnote{\textbf{Contact Address:} Hamid Reza Rajab Larijani, Islamic Azad University (varamin branch), Agronomy, No4.zamani. Lotfalikhani. Homayoonshahr Lonoobi. Daryano.satarkhan, 1459854391~Tehran, Iran, \mbox{e-mail}: \email{larijani2004@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Hamid Reza Rajab Larijani$^{1}$, Majid Aghaalikhani$^{2}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Islamic Azad University (varamin branch), Agronomy, Iran}}}
\item[]{\small{\textit{$^{2}$Tarbiat Modares University, Agronomy, Iran}}}
\end{itemize*}
\index[author]{Rajab Larijani, Hamid Reza}
\index[author]{Aghaalikhani, Majid}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
     In order to investigate chemical, cultural and integrated weed control in winter canola (\textit{Brassica napus} L. cv. Hyola), a field experiment was conducted at Varamin, Iran, on 2007--2008 growing season. Seven experimental treatments were arranged in randomised complete blocks with four replications. Treatments consisted of (1): Chemical weed control using Trifluralin (2.5 l.ha$^{-1}$) before sowing the crop + sethoxydim (1 l.ha$^{-1}$) at stem elongation stage, (2): Integrating the reduced dose of  the same herbicides + between rows cultivation at stem elongation stage, (3): Mechanical weed control through cultivation before canola rosette and at stem elongation stage, (4): Integrating the pre"=irrigation, 25 days before sowing, with cultivation at stem elongation stage, (5): black plastic mulch, (6): weed"=free control (thorough the growth season) and  (7): Weed infested control. Relative weed frequency and dry matter were measured at the stage of silique set initiation. According to the results dominant weed species were turnip weed (Rapistrum rugosum), flixweed (Descurainia sophia), londen rocket (Sisymbrium irio) and wild oats (Avena fatua). Results indicated that canola grain yield and yield components were significantly decreased due to weed interference. The highest crop height, leaf area index and grain yield obtained from black plastic mulch treatment. This weed control treatment has also significantly reduced weed density and dry matter. Effects of treatments number 4, 5 on all weed and crop traits were statistically the same with weed free control treatment. Since mulching practices in canola trade fields is so difficult and relatively expensive, simple integrated (agronomic and mechanical)  weed control treatment including irrigation the field 25 days before planting with the aim of removing emerged winter weeds via seedbed preparation practices + cultivation at stem elongation stage  is recommended. }

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\noindent \textbf{Keywords:} Cultivation, herbicide, mulching, weed control, winter canola
\index[key]{Cultivation}
\index[key]{Herbicide}
\index[key]{Mulching}
\index[key]{Weed control}
\index[key]{Winter canola}
\end{document}