Title: Phytotoxic effects of multi-purpose tree species on germination and growth of Parthenium hysterophorus L.
The current study was conducted to test the inhibitory potential of aqueous extracts and dry shoot residues of four multipurpose tree species (Albizia gummifera, Azadirachta indica, Melia azedarach and Sesbania sesban) on seed germination and seedling growth of an invasive alien weed Parthenium hysterophorus under laboratory and greenhouse conditions. Leaf aqueous extracts and dry residues of all the multi-purpose tree species drastically inhibited germination and seedling growth of parthenium. Parthenium radicle was more inhibited than plumule in Petri dishes. Inhibitory effects increased with increasing aqueous extract concentration and residue amount. Soil surface-placed leaf residues exerted strong reduction on germination and growth of parthenium than soil-incorporated residues. In contrast to the higher inhibitory effects in Petri dishes, lower inhibitory effects were observed by the aqueous extracts of the multi-purpose tree species in pot-culture. Therefore, further investigations will be required under greenhouse and field conditions for pragmatic recommendation of species selection in the frame of multi-purpose tree species-mediated ecological management of parthenium weed. [Mulatu Wakjira, Gezahegn Berecha & Befekadu Bulti (2011). Phytotoxic effects of multi-purpose tree species on germination and growth of Parthenium hysterophorus L. International Journal of Agricultural Research, 6(2), 149-162, doi: 10.3923/ijar.2011.149.162]