Biocontrol of weeds with allelopathy: Conventional and transgenic approaches

Abstract

Growing highly allelopathic crops has the potential to significantly reduce our reliance on synthetic herbicides for weed management. Specific phytotoxins have been found in allelopathic rice, wheat, and rye varieties, but this information has not been used in breeding varieties that can be marketed on the basis of their weed management properties. Although such a conventional approach is viable, transgenic strategies may be better. For example, genes encoding enzymes of the highly potent phytotoxin sorgoleone in Sorghum spp. might be transgenically manipulated to enhance the allelopathic properties of sorghum crops. This potent phytotoxin is exclusively synthesized and secreted by root hairs. The sorgoleone pathway has been elucidated and putative genes encoding them have been identified and partially verified. © 2007 Springer.