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\hypersetup{pdftitle={Allelopathic Strategies for Ecological Weed Management},pdfauthor={S.s. Narwal},pdfsubject={Tropentag 2010: Abstract},pdfkeywords={Allelochemicals, allelopathy, Ecological Agriculture, Herbicides, Weed Management},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{Allelopathic Strategies for Ecological Weed Management\footnote{\textbf{Contact Address:} S.s. Narwal, Ccs Haryana Agricultural University, Hisar-125004, India, Department of Agronomy, Allelopathy Journal 101 Sector-14, 124 001~Rohtak, India, \mbox{e-mail}: \email{narwal_1947@yahoo.com}}\\[0.8ex]}}
\normalsize{\textsc{S.s. Narwal}}
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\begin{itemize*}
\item[]{\small{\textit{Ccs Haryana Agricultural University, Hisar-125004, India, Department of Agronomy, India}}}
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\index[author]{Narwal, S.s.}
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\textbf{Abstract}
\begin{abstract}
\normalsize{
The indiscriminate use of pesticides including herbicides is causing many problems such as environmental pollution and development of tolerance/resistance in pests (insects, nematodes. pathogens and weeds). Therefore, to overcome such problems research is needed on following aspects of crop interference: \textbf{(a)}~In the world about 500 domesticated plant species are grown as crops and these plants offer a great scope for selection of weed smothering species. \textbf{(b)}~Within the promising crops, their varieties may be screened for smothering potential. \textbf{(c)}~The genes responsible for production of smothering allelochemicals may be identified and possibly transferred to new varieties of the same or other crops using latest techniques of biotechnology so that plants could produce their own herbicides. \textbf{(d)}~Research efforts may be directed to utilise microbial and fungal toxins to control weeds. \textbf{(e)}~New and cheap synthetic analogues of natural products having greater selectivity, stability and efficacy to control weeds may be developed. (f) The agronomical practices (sowing time, plant population, row spacing, crop geometry, crop mixture/intercropping) may be further improved to provide competitive edge to the crops over weeds. (g) Crop rotations with allelopathic crops to control weeds may be developed. 



In view of the numerous problems arising from the chemical weed control, questions have been raised about the continuous use of herbicides. Hence, alternative approaches free from such problems needs to be considered. Use of crop allelopathy and allelochemicals for weed control is a sound alternative provided more information is generated. Crop interference and allelochemicals may be used in future to partially/fully replace herbicides to save our planet earth and future generations from ill effects of present hazardous herbicides.



}

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\noindent \textbf{Keywords:} Allelochemicals, allelopathy, Ecological Agriculture, Herbicides, Weed Management
\index[key]{Allelochemicals}
\index[key]{Allelopathy}
\index[key]{Ecological!Agriculture}
\index[key]{Herbicides}
\index[key]{Weed Management}
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