\documentclass[english,german]{scrartcl}
\usepackage{fontspec}
\usepackage{geometry}
\geometry{verbose,a4paper,tmargin=1.75cm,bmargin=2cm,lmargin=2cm,rmargin=2cm,headheight=0.8cm,headsep=0.5cm,footskip=0.5cm}
\usepackage{babel}
\usepackage{url}
\urlstyle{same}
\newcommand\email{\begingroup \urlstyle{same}\Url}\usepackage{graphicx}
\usepackage{units}
\usepackage{tabularx}
\usepackage{wasysym} % enable use of \permil instead of \textperthousand
\usepackage{marvosym}
\usepackage{hyphenat}
\usepackage{booktabs}
\usepackage{mdwlist}
\renewcommand{\thefootnote}{\relax}
\usepackage{index}
\newindex{key}{kdx}{knd}{Keywords}
\newindex{author}{idx}{ind}{Authors}
\usepackage{fancyhdr}
\pagestyle{fancy}
\renewcommand{\headrulewidth}{0pt}
\fancyfoot{}
\usepackage{ifpdf}
\ifpdf
%\usepackage[activate]{pdfcprot}
%\usepackage[owner=Tapioka, print=true, copy=true, edit=false, annotate=false,set]{pdfcrypt}
%encryption: not supported any more (since pdftex 1.10)
\usepackage[pdftex]{thumbpdf}
\usepackage[pdftex]{hyperref}
\hypersetup{pdftitle={Phosphorus Acquisition Efficiency in Rice: Does Carbon Supply Limit Root Growth under Extreme P Deficiency?},pdfauthor={Alejandro Pieters, Stuerz Sabine, Folkard Asch},pdfsubject={Tropentag 2020: Abstract},pdfkeywords={Carbohydrates, carbon partitioning, IR64, Oryza sativa, photosynthesis},pdfpagemode=None,colorlinks=true}
\else
\usepackage{textcomp}
\fi
\begin{document}
\ifpdf
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2020.jpg}}}
\else
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2020.eps}}}
\fi
\hfill
\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 9-11, 2020, virtual conference}}\\[1ex] \Large{``Food and nutrition security and its resilience\\ to global crises''\\[2ex]}}
\hspace{0.1cm}
\begin{center}
\Large{\textbf{Phosphorus Acquisition Efficiency in Rice: Does Carbon Supply Limit Root Growth under Extreme P Deficiency?\footnote{\textbf{Contact Address:} Alejandro Pieters, University of Hohenheim, Inst. of Agric. Sci. in the Tropics (Hans-Ruthenberg-Institute), Garbenstr. 13, 70599 ~Stuttgart, Germany, \mbox{e-mail}: \email{alejandro.pieters@uni-hohenheim.de}}\\[0.8ex]}}
\normalsize{\textsc{Alejandro Pieters, Stuerz Sabine, Folkard Asch}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{University of Hohenheim, Inst. of Agric. Sci. in the Tropics (Hans-Ruthenberg-Institute), Germany}}}
\end{itemize*}
\index[author]{Pieters, Alejandro}
\index[author]{Sabine, Stuerz}
\index[author]{Asch, Folkard}
\begin{center}
\vspace{1.1cm}
\textbf{Abstract}
\begin{abstract}
\normalsize{
Phosphorus (P) acquisition efficiency (PAE) depends largely on a large root system. For high PEA varieties, enlarging the root system under P deficiency requires increased carbon partitioning towards the roots under conditions that also limit photosynthesis. Thus, root growth under P deficiency could be carbon limited. To test this hypothesis, we grew four rice genotypes (DJ123, Kasalath, Santhi Sufaid, high PAE, and IR64 a low PAE check), in hydroponics under glasshouse conditions and provided them with either high (0.32 mM) or low (0.0032 mM) P in the nutrient solution for 50 days. Photosynthetic rate was measured, plant dry weight and carbohydrate concentrations in leaves and roots were determined. Under high P supply shoot and root dry weight was different amongst varieties ($p < 0.001$). P deficiency decreased total and organ biomass but the impact was genotype specific as depicted by a significant PxG interaction ($p < 0.001$). P deficiency increased the root to shoot ratio and high PAE genotypes showed the largest increases compared to IR64. At high P supply photosynthesis rate differed amongst varieties and decreased under P deficiency ($p < 0.001$), the most affected variety was Kasalath and the least affected was Santhi Sufaid, both high PAE varieties. Sucrose concentrations in leaf blades and roots were lower in P starved plants than in high P plants. Starch concentrations in leaves increased under P deficiency but decreased in roots. Root dry weight was hyperbolically related to photosynthesis and linearly related to starch concentration in roots. Our results suggest that root growth under P deficiency could be limited by carbon supply, as leaf sucrose concentrations decreased importantly under P deficiency. However, whether the increase of leaf starch under P deficiency represents unused carbon due to restricted growth or contributes to maintain P homeostasis within the chloroplast allowing photosynthesis to continue, remains to be elucidated. Under these circumstances, selecting for high photosynthetic rates under P deficiency, coupled to an efficient translocation of assimilates to roots could contribute to breeding for high PAE in rice.  }

\vspace{0.5cm}
\end{abstract}
\end{center}
\noindent \textbf{Keywords:} Carbohydrates, carbon partitioning, IR64, \textit{Oryza sativa}, photosynthesis
\index[key]{Carbohydrates}
\index[key]{Carbon partitioning}
\index[key]{IR64}
\index[key]{Oryza sativa@\textit{Oryza sativa}}
\index[key]{Photosynthesis}
\end{document}
