02311naa a2200289 a 450000100080000000500110000800800410001910000260006024500950008626000090018152014350019065000160162565000130164165000160165465000100167065000150168065000280169565000260172365000280174965300250177765300190180265300280182165300200184965300230186970000200189277301090191214005192022-06-29       2000    bl uuuu     u00u1 u    #d1 aSOUZA FILHO, A. P. S.  aAllelopathic potential of pasture weedsbeffects on forage legumes.h[electronic resource]  c2000  aAqueous extracts from aerial parts and seeds ofthe pasture weeds Desmodium adscendens (desmodio), Sida rhombifolia (guanxuma) and Vemoniapo/yanthes (assapeixe) were prepared in a l 0% concentration to identify the allelopathic potential ofthese plants on forage legumes Leucaena leucocephala (leucaena), Stylosanthes guianensis cv. Mineirao (Mineirao) and Cafopogonium mucunoides (calopogonio), and also to verify if pRãnd ionic concentration of extracts can affect the results of allelopathy bioassays. Each aqueous extract was analyzed for pH, conductivity and osmotic potential. The effects ofthe osmotic potential on the results were determined. The results showedthat pH and ionic concentration had no affect. Allelopathic potential activity had variation in function ofthe donor and recipient species specificity and also in function ofthe organs ofthe donor species used in the extract preparation. D. adscendens (desmodio) and S. rhombifolia (guanxuma) were the species that increased reduction ofseeds germination and radic1eelongation, respectively. The aerial organs of donor species were the principal source ofwater-soluble compounds with potential allelopathic effects. L.leucocephala was the forage legume that showed more potential for use in the establishment of a grass-legume pasture of a more stable kind when considering the allelopathic potential ofthe weeds D. adscendens, S. rhombifolia and V. polyanthes.  aallelopathy  aextracts  agermination  aseeds  aAlelopatia  aCalopogonium Mucunoides  aLeucaena Leucocephala  aStylosanthes Guianensis  aDesmodium adscendens  aExtrato aquoso  aGerminação de semente  aSidarhombifolia  aVemonia polyanthes1 aALVES, S. de M.  tQuarterly Reports on Plant Growth Regulation and Activities of the PGRSAgv. 28, n. 4, p. 146-156, 2000.