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\hypersetup{pdftitle={The Rate of Nitrogen Conversion to Protein in Leaves of Wheat Affected by Nickel},pdfauthor={Saadollah Teimouri, Naser Khaleghpanah, Mohammad  Nabi Gheibi, Rayehe Mirkhani, Mehdi Samavati},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Nickel, Nitrogen, Protein content, wheat},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{The Rate of Nitrogen Conversion to Protein in Leaves of Wheat Affected by Nickel\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$^{1}$, Naser Khaleghpanah$^{1}$, Mohammad  Nabi Gheibi$^{2}$, Rayehe Mirkhani$^{1}$, Mehdi Samavati$^{1}$}}
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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]{Khaleghpanah, Naser}
\index[author]{Gheibi, Mohammad  Nabi}
\index[author]{Mirkhani, Rayehe}
\index[author]{Samavati, Mehdi}
\begin{center}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
Nickel has been listed as an essential micronutrient. It is required for the urease enzyme, which hydrolyses urea. The present study was designed to investigate the rate of nitrogen conversion to protein in leaves of wheat plants. Previous experiments shown that the amount of nickel for optimum wheat growth when supplied with ammonium nitrate or urea were 0.01 and 0.05 mg L$^{-1}$ of nutrient solutions respectively. Plants were treated with two Nitrogen sources: urea and ammonium nitrate with two nickel levels (0 and optimum level). Seedlings, 5 day after emergence, were transferred to pots containing the complete nutrient solution in greenhouse. The experiment lasted for 13 days. The amounts of protein in leaf number 4 ammonium nitrate"=fed plants supplied with nickel more than in those grown in the absence of nickel. However in urea"=grown plants, this was true till day 8 of sampling time. In plants grown on urea with nickel supplementation, the amount of protein was the highest in sampling days of 5\textsuperscript{th}, 6\textsuperscript{th} and 7\textsuperscript{th}.  In general, the leaves protein content in all treatments increased till day 5 and remained the same on days 6 and 7 and started to decrease till day 13. Increase in protein production in urea"=fed plants with nickel optimum level supply is most probably attributed to activation of urease enzyme and higher urease activity by nickel. The increase in protein content in leaves plants supplied with ammonium nitrate and optimum level of nickel can be due to detoxification of endogenous urea by urease. The results show that nickel optimum level increase protein content in leaves of wheat.}

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\noindent \textbf{Keywords:} Nickel, Nitrogen, Protein content, wheat
\index[key]{Nickel}
\index[key]{Nitrogen}
\index[key]{Protein content}
\index[key]{Wheat}
\end{document}