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\hypersetup{pdftitle={Effect of Wild Mustard (\textit{Sinapis arvensis}) Density on Some Agronomic Traits of Canola (\textit{Brassica napus}) Cultivars},pdfauthor={Ali Reza Safahani Langeroudi, Behnam Kamkar, Eskandar Zand, Mohammad Ali Baghestani},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Canola, Oil percentage, Weed density, Wild mustard, Yield components. },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{Effect of Wild Mustard (\textit{Sinapis arvensis}) Density on Some Agronomic Traits of Canola (\textit{Brassica napus}) Cultivars\footnote{\textbf{Contact Address:} Behnam Kamkar, Gorgan University of Agricultural Sciences and Natural Resources, Dept. of Agronomy, Basij Square, Gorgan, Iran, \mbox{e-mail}: \email{bkamkar@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Ali Reza Safahani Langeroudi$^{1}$, Behnam Kamkar$^{2}$, Eskandar Zand$^{3}$, Mohammad Ali Baghestani$^{3}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Islamic Azad University,  Ghaemshar Branch, Iran, Dept. of Agronomy, Iran}}}
\item[]{\small{\textit{$^{2}$Gorgan University of Agricultural Sciences and Natural Resources, Dept. of Agronomy, Iran}}}
\item[]{\small{\textit{$^{3}$Plant Pests and Diseases Research Institute, Weed Research, Iran}}}
\end{itemize*}
\index[author]{Safahani Langeroudi, Ali Reza}
\index[author]{Kamkar, Behnam}
\index[author]{Zand, Eskandar}
\index[author]{Baghestani, Mohammad Ali}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
In order to study effect of wild mustard interferences in some canola cultivars two field experiments were carried out at the Gorgan Institute in Iran during the 2005--2007 cropping seasons. The experimental factors were canola cultivars (1\textsuperscript{st} year: Zarfam, Option500, Hayola330, Hayola401, Talayh, Rgs003 and Sarigol; 2nd year: Zarfam, Hayola330, Rgs003 and Option500) and weed density (1\textsuperscript{st} year: control and 30 plants m$^{-2}$; 2nd year: control, 4, 8 and 16 plants m$^{-2}$). Seed yield, harvest index, number of siliques/plant, number of seed/silique, 1000-seed weight, seed oil percentage and nitrogen harvest index were measured. Results showed significant differences in seed yield between cultivars. Results also indicated significant differences in yield components and weed"=infesteded conditions, but interference had no drastic effect on seed oil percentage and 1000-seed weight. In first year and under weed"=free condition, the highest and lowest seed yield with averages of 2836 and \unitfrac[1729]{kg}{ha} belonged to Cultivars Hayola330 and Talayh, respectively. But under weed infested condition, Cultivars Hayola330 and Option500 produced the highest and lowest seed yield with averages of 870 and \unitfrac[101]{kg}{ha}, respectively. In second year and under weed"=infested conditions, the lowest and highest yield loss percentage with averages of 42 and \mbox{88\,\%} belonged to cultivars Zarfam and Option500, respectively. Increasing wild mustard density decreased canola seed yield, biological yield with a nonlinear trend. The results of this study suggest that competitive canola cultivars may be best suited for use in an integrated weed management program, particularly for farmers of organic or low input cropping systems. }

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\end{abstract}
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\noindent \textbf{Keywords:} Canola, Oil percentage, Weed density, Wild mustard, Yield components. 
\index[key]{Canola}
\index[key]{Oil percentage}
\index[key]{Weed density}
\index[key]{Wild mustard}
\index[key]{Yield!components. }
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