Weed control cover crops

Study 2. The effects of wheat, oats, barley and rye mulches on three broadleaf weed species and crabgrass (Digitaria spp.) are shown in Table VI. Weed control data for the corn test at Kinston are not presented because of poor cover crop kill by the paraquat treatment. 

Cover crops Improves fertility Improves water availability Nutrient recycling Reduces costs Soil erosion and runoff control Weed control Kalinova (2009) Malezieux et al. (2009) Pati et al. (2009) Runyon et al. (2009) Stagnari et al. (2009) Wu and Sardo (2009) Zuazo and Pleguezuelo (2009)... 

Allelopathic interactions of plants can provide weed control by (a) use of allelopathic crops as cover crops, mulches or green manure, (b) use of allelopathic plants in crop rotations, (c) crop mixtures and intercropping, (d) varieties with strong allelopathic potential, and (e) use of allelopathic crop water extracts and other agents. 

Fig. 14.2 Well established stand of common buckwheat as a cover crop has great weed suppressive effects. Buckwheat emits allelochemicals, thus controlling weeds... 

Providing weed suppression through the use of allelopathic cover crops is an important method of weed control in organic farming and it is one of the best possibilities of allelopathy application (Sullivan 2003a). Besides, growing of cover... 

Table 14.2 Examples of possible use of some cover crops in effective control of some weeds... 

Except direct use of allelopathic crops as cover crops, smother crops, and intercrops, applications of allelopathy for weed control include the use of allelopathic residues as an herbicide agent, e.g., pellets flours, water extracts, etc. The most common example of crop residue utilization is application of straw on the soil surface (mulching), e.g., rice straw inhibited germination of field bindweed (Convolvulus arvensis L.), winter wild oat (Avena ludoviciana Durieu), and little-seed canarygrass (Phalaris minor Retz.) (Lee et al. 1991 Tamak et al. 1994 Young et al. 1989). 

Rasmussen IA (2004) The effect of sowing date, stale seedbed, row width and mechanical control on weeds and yields of organic winter wheat. Weed Res 44 12-20 Reddy KC (2001) Effects of cereal and legume cover crop residues on weeds yield, and net return in soybean (Glycine max),. Weed Tech 15 660-668 Reynolds LB, Potter JW, Ball-Coelho BR (2000) Crop rotation with Tagetes sp. is an alternative to chemical fumigation for control of root-lesion nematodes. Agron J 92 957-966 Rice EL (1984) Allelopathy. Academic, New York, p 317... 

In permanent crops a higher species diversity can be attained by applying a cover crop rotation for weed control. This is reported for organie olive production (Kabourakis 1996). 

While allelopathy is not covered in this chapter, excellent weed control can be achieved at reduced herbicide rate when used in conjunction with allelopathic rice varieties. Therefore, selection of highly allelopathic crop varieties, either through traditional breeding or using genetic engineering techniques, may also provide novel and low input approaches to weed control. 

Brandsseter, L.O. and Riley, H. 2002. Cover crops and mulches for weed control in organically grown vegetables. In Cloutier, D.C. (ed.) Proceedings of the 5th EWRS Workshop on Physical and Cultural Weed Control. European Weed Research Society, Pisa. p. 174. 

Hutchinson, C.M. and McGiffen, M.E. 2000. Cowpea cover crop mulch for weed control in... 

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