\documentclass[english,german]{scrartcl}
\usepackage[latin1]{inputenc}
\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{arabtex}
\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={Symptoms Development of Peronospora Sparsa under Greenhouse Conditions at the Bogotá Plateau, Colombia},pdfauthor={Sandra Gomez, German Arbelaez},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Downy mildew, incubation period, rootstocks},pdfpagemode=None,colorlinks=true}
\else
\usepackage{ae}
\usepackage{textcomp}
\fi
\begin{document}
\ifpdf
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2010.jpg}}}
\else
\parbox[b]{2.5cm}{\resizebox*{2.5cm}{!}{\includegraphics{dtt2010.eps}}}
\fi
\hfill
\parbox[b]{13.4cm}{\centering \large{\textbf{Tropentag, September 14-16, 2010, Zurich}}\\[1ex] \Large{``World Food System  ---\\A Contribution from Europe''\\[2ex]}}
\hspace{0.1cm}
\begin{center}
\Large{\textbf{Symptoms Development of Peronospora Sparsa under Greenhouse Conditions at the Bogotá Plateau, Colombia\footnote{\textbf{Contact Address:} Sandra Gomez, National University of Colombia, Faculty of Agronomy, Carrera 45 N 26-85, Bogota, Colombia, \mbox{e-mail}: \email{sgomezc@unal.edu.co}}\\[0.8ex]}}
\normalsize{\textsc{Sandra Gomez$^{1}$, German Arbelaez$^{2}$}}
\end{center}
\begin{itemize*}
\item[]{\small{\textit{$^{1}$National University of Colombia, Faculty of Agronomy, Colombia}}}
\item[]{\small{\textit{$^{2}$National Unversity of Colombia, Faculty of Agronomy, }}}
\end{itemize*}
\index[author]{Gomez, Sandra}
\index[author]{Arbelaez, German}
\begin{center}
\vspace{1.1cm}
\textbf{Abstract}
\begin{abstract}
\normalsize{




Downy mildew causes direct losses in rose crops under greenhouses in the tropics due to the affection of flowers and indirect losses by defoliation of plants. In addition, plants recovering following a severe attack by this disease takes several months. In Colombia producers estimated losses of \mbox{10\,\%} of annual gross production. This corresponds to US \$20,000 per hectare growing a susceptible rose variety. The objective of this study was to evaluate the development of the symptoms caused by downy mildew in rose plants under greenhouse conditions. For this purpose healthy rose plants of cultivars Charlotte, Classy and First Red were grafted on Natal Briar and Manetti rootstocks and plants rooted directly were inoculated with a sporangial suspension of Peronospora sparsa. To register the presence of downy mildew symptoms, the plants were divided in three stratums according to the predominant stage of the development of the foliage and were evaluated daily starting two days after inoculation. The percentage of affected leaves per stratum per variety was established. In addition the degree of the disease in apical leaflets was registered according to the scale proposed in this study. Symptoms of downy mildew were first observed on leaves seven dai. The symptoms on stems occurred 17 and 18 days after spore inoculation in Charlotte variety and between 21 and 28 days in varieties Classy and First Red. The symptoms on flower buds appeared 14 and 16 days after inoculation in Charlotte, 14 days after inoculation in Classy and between 16 and 26 days in First Red plants. Defoliation of affected leaves occurred first in Classy 12 days after inoculations. In variety Charlotte this reaction was observed 18 and 28 days and in First Red plants in a period of 15 and 28 days. No interactions were observed between the rose variety and the plants stratum on the incidence of the disease. 



}

\vspace{0.5cm}
\end{abstract}
\end{center}
\noindent \textbf{Keywords:} Downy mildew, incubation period, rootstocks
\index[key]{Downy mildew}
\index[key]{Incubation period}
\index[key]{Rootstocks}
\end{document}