Allelopathy and its Influence on the Distribution of Plants in an Illinois Old-Field

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Ecology. SUMMARY(1) A whole-community investigation of allelopathy in an old-field in Illinois was undertaken, by comparing bioassay results with association patterns in the field.(2) The seven most abundant species in the field were tested upon each other in nine commonly-used bioassays. Eight of the nine bioassays gave many cases of statistically significant inhibition, and strong phytotoxicity was exhibited by species which have not previously been suspected of being allelopathic and which show no readily-observable signs of allelopathy in the field.(3) Autotoxicity was found to be as severe as allotoxicity, indicating that the species have not evolved resistance to their own inhibitors.(4) When the distribution patterns of species in the field were statistically compared with the results of each of the bioassays in turn, no significant correlations were found.(5) It was concluded that the types of allelopathy which were tested by these bioassays were not demonstrably effective under field conditions, that perhaps any species can be shown to have allelopathic properties in bioassays, and that bioassays may, for many communities, have no ecological meaning.

Allelopathic effects of juglone on germination and growth of several herbaceous and woody species

“…However, biological assays are insufficient as a means of identifying the occurrence of allelopathy and the concentrations of chemicals responsible for allelopathy in the field (Stowe, 1979). Although natural juglone concentrations have not been measured in the field and are therefore unknown, it is unlikely that 10 -3 M juglone occurs in soil under field conditions.…”

Phytotoxicity induced by Phragmites australis: an assessment of phenotypic and physiological parameters involved in germination process and growth of receptor plant

“…In field conditions, several mechanisms of interference might be operative in sequence and simultaneously so it makes it difficult to separate the general interference effects from those of allelopathy. Furthermore, various authors speculate that seed germination may not be the primary site for allelopathic interactions (Stowe 1979;Lorenzo et al 2010). Relatively little is known about the physiological and biochemical effects induced by allelochemical phytotoxicity in seed germination and seedling growth (Weir et al 2004;Lorenzo et al 2011) though that contributes to the fitness and survival of plants in competition with other species.…”

Potencial alelopático de plantas de acapu (Vouacapoua americana): efeitos sobre plantas daninhas de pastagens

“…A concentração máxima de 5% foi estipulada considerando-se que é aquela mais comumente utilizada em bioensaios de alelopatia usando extratos aquosos (Stowe, 1979). Os extratos aquosos Potencial alelopático de plantas de acapu (Vouacapoua americana): efeitos sobre ... foram deixados em repouso por seis horas, sendo então novamente filtrados.…”