Investigating the Allelotoxic Activity of Eucalyptus rostrata Schlecht. on Seed Germination and Seedling Growth of Chenopodium album L. and Portulaca oleracea L.

Eucalyptus rostrata is known to contain a variety of allelopathic substances. The allelopathic effect of Eucalyptus rostrata leaf (ERLAE) and bark (ERBAE) aqueous extracts on seed germination and seedling growth of two noxious weeds, Chenopodium album and Portulaca oleracea, was investigated. The biological activity of the two types of extracts on germination efficiency varies depending on the extract type and recipient species. The effect of the extracts on the two weeds was in the following order: ERLAE > ERBAE, and the action was almost as effective and significant in C. album as it was in P. oleracea. The reduction in plumule and radical lengths observed in the current study may be attributed to a slower rate of cell division and elongation caused by the presence of allelochemicals in the aqueous extracts. In conclusion, the current study's findings may contribute to the solution of the problem of excessive use of synthetic herbicides through the application and testing of a number of promising medicinal plants rich in allelochemicals, such as E. rostrata.