02229naa a2200241 a 450000100080000000500110000800800410001902400500006010000220011024501390013226000090027152014490028065000190172965000150174865300260176370000180178970000150180770000240182270000190184670000240186570000170188977300810190621228482020-06-01       2020    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1021/acs.jafc.0c003072DOI1 aFEITOZA, R. B. B.  aEvaluation of the phytotoxicity of Urochloa humidicola roots by bioassays and microscopic analysisbcharacterization of new compounds.  c2020  aHerbicides are a key element in agriculture but they do cause environmental problems and natural alternatives are being sought. In this context, invasive plants could provide an as yet unexplored source for the development of future herbicides. Urochloa humidicola has great invasive potential in Brazilian environments as it hampers the establishment of other plants. The phytotoxicity of U. humidicola root extracts has been evaluated, and the major components have been identi?ed. The phytotoxicity of the extract was assessed in the wheat coleoptile assay on seeds of troublesome weeds and on Anadenanthera colubrina, a tree species used in ecological restoration programs. The ethyl acetate extract showed the highest activity, and the most a?ected weeds were E. crus-galli, M. maximus, and A. viridis with the latter weed more a?ected by the extract than by the herbicide Logran. Microscopic ultrastructural analysis of A. colubrina roots indicated possible signals of cell death. Seven compounds were identi?ed in the ethyl acetate extract of which one diterpene and four saponins are new. Six of these compounds were tested in the wheat coleoptile bioassay. The most active were diterpene 1 and saponins 2, 3, and 6. The phytotoxic activity of U. humidicola explains the issues. observed in ecological restoration with A. colubrina in the presence of Urochloa species, and its e?ect on weeds reinforces its potential use in agriculture.  aUltrastructure  aBrachiaria  aAlternative herbicide1 aVARELA, R. M.1 aTORRES, A.1 aMOLINILLO, J. M. G.1 aLIMA, H. R. P.1 aMORAES, L. F. D. de1 aCUNHA, M. da  tJournal of Agriculture and Food Chemistrygv. 78, n. 17, p. 4851-4864, 2020.