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\hypersetup{pdftitle={Effects of Pinus taeda Plantation, as an Exotic Species, on Arbuscular Mycorrhizal  Fungal Community in Comparision to Natural Forest},pdfauthor={Hamid Reza Saeidi, Moslem Akbarinia},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Arbuscular mycorrhizal fungi, mixed decidous stands, Pinus taeda plantation},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{Effects of Pinus taeda Plantation, as an Exotic Species, on Arbuscular Mycorrhizal  Fungal Community in Comparision to Natural Forest\footnote{\textbf{Contact Address:} Hamid Reza Saeidi, Tarbiat Modares University, Department of Forestry, Motahari, 46917-44993~Ramsar, Iran, \mbox{e-mail}: \email{hrsaeidi@gmail.com}}\\[0.8ex]}}
\normalsize{\textsc{Hamid Reza Saeidi, Moslem Akbarinia}}
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\begin{itemize*}
\item[]{\small{\textit{Tarbiat Modares University, Department of Forestry, Iran}}}
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\index[author]{Saeidi, Hamid Reza}
\index[author]{Akbarinia, Moslem}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
We assessed spore density, percentage of root length colonized (RLC\%) by arbuscular mycorrhizal fungi and mycorrhizal infectivity potential (MIP) in natural forest (mixed decidous stands) and \textit{Pinus taeda} plantation. Early autumn, sampling was carried out from the rhizosphere of understory dominant species. The same soil samples were carefully mixed and spores were extracted using the wet sieving method. To assess percentage of root length colonisation by AM fungi, the roots were harvested, stained, and scored using the grid"=line intersect method.  Mycorrhizal infectivity potential (MIP) was evaluated in two stands using corn seedlings (\textit{Zea mays}) as trap culture. Physical and chemical parameters of soil samples such as texture, total N, P, K, Mg and Ca contents, percent of organic carbon, soil reaction (pH), moisture saturation percent and electrical conductivity (EC) were measured. We used Pearson correlation analysis to relate spore density and root colonisation with soil properties. The analysis of differences between means was done with independent sample t"=test. The results showed that there is significant difference between spore abundance in two stands. The number of spore was 2.6 and 1.9 per gram of dry soil in natural stand and forest plantation, respectively. However, the percentage root length colonized by AM fungal was 9.5 and 10 in pinus taeda plantation and natural stands respectively and there is no significant difference between two stands. The MIP in natural decidous stands is significantly higher than \textit{Pinus taeda} plantation.  A positive correlation was found between spore abundance and moisture saturation, sand percent, total N and Ca content, but was inversely related to the soil reaction (pH) and organic carbon. Total percentage of root length colonisation showed significant positive correlation to soil parameters such as Ca content and spore abundance, while was negatively correlated to soil reaction (pH).  }

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\noindent \textbf{Keywords:} Arbuscular mycorrhizal fungi, mixed decidous stands, Pinus taeda plantation
\index[key]{Arbuscular mycorrhizal fungi}
\index[key]{Mixed decidous stands}
\index[key]{Pinus taeda plantation}
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