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\hypersetup{pdftitle={Allelopathic Effect of Wild Mustard (Sinapis Arvensis L.) on Germination and Growth of Wild Oat (Avena Fatua L.)},pdfauthor={Ali Reza Safahani Langeroudi, Behnam Kamkar},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Aqueous extracts, Avena fatua L., Germination, Seedling length, Sinapis arvensis L., wild mustard, Wild oat},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{Allelopathic Effect of Wild Mustard (Sinapis Arvensis L.) on Germination and Growth of Wild Oat (Avena Fatua L.)\footnote{\textbf{Contact Address:} Ali Reza Safahani Langeroudi, Islamic Azad University,  Ghaemshar Branch, Iran, Dept. of Agronomy, Gorgan, Iran, \mbox{e-mail}: \email{safahani_ali@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Ali Reza Safahani Langeroudi$^{1}$, Behnam Kamkar$^{2}$}}
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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}}}
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\index[author]{Safahani Langeroudi, Ali Reza}
\index[author]{Kamkar, Behnam}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Members of Brassicaceae have frequently been cited as allelopathic crops. Some Brassica species have harmful effects on crops including reduced seed germination and emergence of subsequent small"=grain crops when grown in rotation. Wild mustard (Sinapis arvensis L.) contains water"=soluble substances that inhibited the germination and seedling growth of wild oat (Avena fatua L.). Determining where allelochemicals may be found in S. arvensis in the greatest concentration would aid in trying to isolate the compound or compounds responsible for autotoxicity. The study was conducted at Gorgan University during the year 2009. This study investigated the allelopathic effects of various S. arvensis plant parts on A. fatua L. germination and seedling growth. Aqueous extracts of S. arvensis leaf, stem, flower and root plant part were made to determine their effects on germination and dry weights of hypocotyl and radicle length of 8-d old A. fatua L. seedlings over a range of extract concentrations. Increasing the aqueous extract concentrations of separated S. arvensis L., plant parts significantly inhibited A. fatua L. germination, seedling length and weight. Radicle length was more sensitive to extract source than seed germination or hypocotyl length. Based on 8-d"=old A. fatua L.plant radicle length growth, averaged across all extract concentrations, the degree of toxicity of different S. arvensis plant parts can be classified in order of decreasing inhibition as follows: leaf, mixture of all plant parts, flower, stem and root. Soil incorporation of fresh S. arvensis roots only or both roots and shoots reduced A. fatua emergence, plant height, and dry weight per plant.}

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\noindent \textbf{Keywords:} Aqueous extracts, Avena fatua L., Germination, Seedling length, Sinapis arvensis L., wild mustard, Wild oat
\index[key]{Aqueous extracts}
\index[key]{Avena fatua L.}
\index[key]{Germination}
\index[key]{Seedling length}
\index[key]{Sinapis arvensis L.}
\index[key]{Wild mustard}
\index[key]{Wild oat}
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