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\hypersetup{pdftitle={Allelopathic Potential of Artemisia Herba Alba Asso on Seed Germination and Seedling Growth of Three Grass Species},pdfauthor={Farzaneh Gholami, Behzad Behtari, Ghasemali Dianati Tilaki},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Allelopathic potential, Artemisia herba alba, Artemisia ketone, Cis– pinocarveol, essential oils, grass},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 Potential of Artemisia Herba Alba Asso on Seed Germination and Seedling Growth of Three Grass Species\footnote{\textbf{Contact Address:} Farzaneh Gholami, Tarbiat Modares University, Natural Resources, P.O.Box 14115-111, Tehran, Iran, \mbox{e-mail}: \email{f_gholami_64@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{Farzaneh Gholami, Behzad Behtari, Ghasemali Dianati Tilaki}}
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\begin{itemize*}
\item[]{\small{\textit{Tarbiat Modares University, Natural Resources, Iran}}}
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\index[author]{Gholami, Farzaneh}
\index[author]{Behtari, Behzad}
\index[author]{Dianati Tilaki, Ghasemali}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Artemisia herba alba Asso is a widely distributed plant that grows in many areas of Iran Allelopathy is the direct influence of a chemical released from one plant on the development and growth of another. This studying order to investigate the allelopathic potential of essential oils concentration of Artemisia herba alba on germination and seedling growth of lolium perenne, Secale montanum and Bromus tomentellus was evaluated on an completely randomised design with three replicates in laboratorial conditions. Aerial parts of A. herba"=alba were shade dried at room temperature. Essential oil was extracted from the aerial parts of Artemisia herba"=alba Asso using a Clevenger-Type apparatus and Gas chromatographic analysis was performed with GC/Mass. Germination test was carried out in a temperature controlled germinator held at 15---25 °C. Fifty seeds were placed on two layers of filter paper moistened with concentration 0.0 (distilled water), 100ppm, 300ppm, 500ppm and 700ppm of essential oil in covered \mbox{9\,cm} Petri dishes. Results showed that with increasing concentration essential oils of Artemisia herba alba from 100 ppm to 700 ppm decreased germination percentage, germination speed, shoot and root length of three grass species. In our research was detected 32 chemotypes in essential oils of A. herba alba that Cis---pinocarveol and Artemisia ketone the major constituents of A. herba alba oil and may play an important role in the allelopathy of A. herba alba. Generally, the inhibition efficiency was found to increase with concentration essential oils. Essential oil acts as cathodic inhibitors with modifying the hydrogen reduction mechanism and this agent the cause decreased seed germination and seedling growth in species of grass.}

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\noindent \textbf{Keywords:} Allelopathic potential, Artemisia herba alba, Artemisia ketone, Cis--- pinocarveol, essential oils, grass
\index[key]{Allelopathic potential}
\index[key]{Artemisia herba alba}
\index[key]{Artemisia ketone}
\index[key]{Cis--- pinocarveol}
\index[key]{Essential oils}
\index[key]{Grass}
\end{document}