Fungal Phytotoxins — Potential New Herbicides
The desire for selective, less persistent herbicides has generated interest in Phytotoxins as potential chemicals with applicability as agrochemicals (Cutler, 1986; Duke, 1986; Strobel et. al., 1987). Phytotoxins are natural compounds which have a deleterious effect on plants. Of particular interest in the present context are those toxins produced by microbes, usually pathogens, which make their living on weedy plants. These pathogens are first noticed because they cause dramatic symptoms such as necrosis, chlorosis, or wilt in their hosts. In laboratories such as ours, attempts are then made to isolate and identify toxic chemicals produced by the pathogens in hopes of establishing molecular leads for the herbicide industry. One spin-off of such studies is the elucidation of intriguing, often novel chemicals which perturb the normal physiological processes of plants in ways not found in the usual approach of organic synthesis followed by screening. Numerous Phytotoxins have been identified in recent decades and the reader is encouraged to consult the overviews cited above for more information.
KeywordsLeafy Spurge Tenuazonic Acid Weedy Plant Spotted Knapweed Green Island
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