Glyphosate-Modulated Biosynthesis Driving Plant Defense and Species Interactions

Residues of glyphosate, a potent herbicide, are increasingly found in diverse environments.Glyphosate residues soil alter plant physiological processes; however, their effects on defense strategies and subsequent species interactions poorly understood.Glyphosate inhibition the shikimate pathway affects defense-related phytohormones phenylpropanoid pathway, basis for many phytoalexins.Glyphosate lipid peroxidation, which alters jasmonic acid levels green leaf volatiles, turn, important players mediating trophic pollinator attraction.By changing biochemistry, glyphosate have potential to with herbivores mutualistic organisms. Glyphosate has become best-selling herbicide used agriculture, horticulture, silviculture, urban environments. It disrupts metabolic thereby blocks production aromatic amino acids, several metabolites. reported soils from environments, but physiology consequences largely unknown. Here, we emphasize complexity these processes, argue that modulate biosynthetic pathways, individually or interactively, may affect between plants heterotrophic In this way, can substantially interfere resistance attraction beneficial insects, both essential elements integrated pest management healthy ecosystems. [N-(phosphonomethyl)-glycine], synthesized broad-spectrum systemic is most widely globally [1.Duke S.O. Powles S.B. Glyphosate: once-in-a-century herbicide.Pest Manag. Sci. 2008; 64: 319-325Crossref PubMed Scopus (1021) Google Scholar]. inhibits 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) (see Glossary), an enzyme catalyzing conversion shikimate-3-phosphate [2.Schonbrunn E. et al.Interaction its target 5-enolpyruvylshikimate 3-phosphate atomic detail.Proc. Natl. Acad. 2001; 98: 1376-1380Crossref (373) The produces chorismate, central precursor molecule acids [3.Amrhein N. al.The site by glyphosate: II. 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Plant. 3: 2-20Abstract (1539) PPs entirely dependent supply, blocked glyphosate. Several confirm decreased flavonoids) following multiple [25.Sharon elicited response: Cassia obtusifolia mycoh