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\hypersetup{pdftitle={Effect of Different Levels of Nickel on Uptake of other Cations in Maize},pdfauthor={Saadollah Teimouri, Mohammad  Nabi Gheibi, Rayehe Mirkhani, Naser Khaleghpanah, Ali Shirzadi},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Compete , Maize, nickel, Other nutrient cations},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 Different Levels of Nickel on Uptake of other Cations in Maize\footnote{\textbf{Contact Address:} Saadollah Teimouri, Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organisation of Iran, Karaj, Iran, \mbox{e-mail}: \email{steimouri@nrcam.org}}\\[0.8ex]}}
\normalsize{\textsc{Saadollah Teimouri$^{1}$, Mohammad  Nabi Gheibi$^{2}$, Rayehe Mirkhani$^{1}$, Naser Khaleghpanah$^{1}$, Ali Shirzadi$^{1}$}}
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\begin{itemize*}
\item[]{\small{\textit{$^{1}$Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organisation of Iran, Iran}}}
\item[]{\small{\textit{$^{2}$Soil Science Department, Tarbiat Modarres  University, Tehran, Iran, }}}
\end{itemize*}
\index[author]{Teimouri, Saadollah}
\index[author]{Gheibi, Mohammad  Nabi}
\index[author]{Mirkhani, Rayehe}
\index[author]{Khaleghpanah, Naser}
\index[author]{Shirzadi, Ali}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Nickel is now generally accepted as an essential ultra micronutrient and its main function is activation of urease enzyme. A greenhouse experiment was conducted to study interaction of nickel with other nutrient cations. Treatment included nutrient solution cultures containing urea and ammonium nitrate at the rate of 84 mg N L$^{-1}$ separately as nitrogen sources with four Ni levels at the rates of 0, 0.01, 0.05 and 0.1 mg L$^{-1}$. Maize plants were harvested six weeks after treatments and total concentration of Ni, Fe, Zn, Mn, Cu, Ca, Mg and K in roots and shoots were determined. Nickel content increased in both shoots and roots with the increase in nickel concentration in nutrient solution. In plants supplied with urea, the amounts of Fe, Mn, Zn, Mg and K uptake increased up to the 4\textsuperscript{th} nickel level that can be attributed to the presence of urea in media and thus more availability of N-urea for growth and development. But in plants supplied with ammonium nitrate, the amounts of these cations uptake increased up to 3\textsuperscript{th} nickel level that may be due to higher urease activity and detoxification of endogenous urea by urease. Further increase in nickel supply led to nickel toxicity and concentration of essential elements was decreased. With increase in nickel supply, copper uptake was decreased but calcium uptake was increased.  As a whole, at nickel concentrations higher than the optimum level, the symptoms of nickel toxicity became visible and nickel competed with other essential cations for absorption by corn root. High concentrations of nickel decreased the uptake of other nutrient cations.}

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\noindent \textbf{Keywords:} Compete , Maize, nickel, Other nutrient cations
\index[key]{Compete }
\index[key]{Maize}
\index[key]{Nickel}
\index[key]{Other nutrient cations}
\end{document}