Parthenium is a potential allelopathic plant which possesses important allelochemicals with known allelopathic activity on other plants. In this, study allelopathic effects of fresh and hot water extracts of leaves, stem, and flowers of Parthenium hysterophorus were investigated on germination and seedling growth of wheat in seed bioassay experiments carried out at department of botany university of Peshawar during 2016. Results showed significantly inhibitory effects of aqueous extracts on seed germination, growth and fresh and dry biomass of seedling wheat. Data revealed that phytotoxicity of the extract increases as the concentration increases the results also showed that hot water extract is more inhibitory than fresh water. It is suggested that Parthenium hysterophorus L. has a strong allelopathic potential and it might be further studied for its allelopathic activities.

Index Terms- Allelopathy, Parthenium hysterophorus, Wheat variety, seed germination and growth.