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Integrating physical and cultural methods of weed control— examples from European research

Published online by Cambridge University Press:  20 January 2017

Bo Melander ,
Ilse A. Rasmussen  and
Paolo Bàrberi
Ilse A. Rasmussen
Affiliation:
Danish Institute of Agricultural Sciences, Department of Integrated Pest Management, Research Centre Flakkebjerg, DK-4200 Slagelse, Denmark
Paolo Bàrberi
Affiliation:
Land Lab, Scuola Superiore Sant'Anna, Piazza Martiri della Libertà 33, I-56127 Pisa, Italy
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Abstract

Increasing concerns about pesticide use and a steadily increasing conversion to organic farming have been major factors driving research in physical and cultural weed control methods in Europe. This article reviews some of the major results achieved with nonchemical methods and strategies, especially adapted for row crops (e.g., corn, sugar beet, onion, leek, and carrot) and small-grain cereals (e.g., barley and wheat). In row crops, intrarow weeds constitute a major challenge, and research has mainly aimed at replacing laborious hand-weeding with mechanization. A number of investigations have focused on optimizing the use of thermal and mechanical weeding methods against intrarow weeds, such as flaming, harrowing, brush weeding, hoeing, torsion weeding, and finger weeding. And new methods are now under investigation such as robotic weeding for row crops with abundant spacing between individual plants and band-steaming for row crops developing dense crop stands. The strategic use of mechanical weed control methods in small-grain cereals has been another area of considerable interest. Weed harrowing and interrow hoeing provide promising results when they are part of a strategy that also involves cultural methods such as fertilizer placement, seed vigor, seed rate, and competitive varieties. Although research in preventive, cultural, and physical methods have improved weed control in row crops and small-grain cereals, effective long-term weed management in low external input and organic systems can only be achieved by tackling the problem in a wider context, i.e., at the cropping system level. Basic principles of this approach, examples of cover crop and intercropping use for weed suppression, and an application in a 2-yr rotation are presented and discussed.

Keywords

Barley, Hordeum vulgare L.carrot, Daucus carota L.corn, Zea mays L.leek, Allium porrum L.onion, Allium cepa L.sugar beet, Beta vulgaris L.wheat, Triticum aestivum L.Mechanical weed controlthermal weed controlpreventive methodsorganic croppinglow-input systems
Type
Symposium
Information
Weed Science , Volume 53 , Issue 3 , June 2005 , pp. 369 - 381
Copyright
Copyright © Weed Science Society of America 

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References

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