Phytotoxic effect of the extracts of Parthenium hysterophorus L. on the germination, seedling growth and biomass of some agricultural crops

This study was conducted to assess the phytotoxic effect of invasive species: Parthenium hysterophorus L. on the germination, seedling length and biomass of Zea mays, Macrotyloma uniflorum and Triticum aestivum, in order to explore its potential as noxious species. In this study, the allelopathic substances were extracted with distilled water and methanol from the aerial and underground part of P. hysterophorus L. in different concentration (1, 100, 150, 400 mg mL–1). The results of the study revealed that the methanol fraction of roots at 400 mg mL-1 concentration had the highest phytotoxic activity as compared to the double distilled water extract. Germination (%) was observed to be maximum (90%) for Z. mays with double distilled water above ground part extract at 1 mg mL-1 and lowest (10%) for M. uniflorum L. in 400 mg mL-1 both aerial and underground plant extracts at the last day of measurement. Mean shoot and root length were observed highest (17.6cm and 6.1cm respectively) in Z. mays with aerial double distilled water extract at 1 mg mL-1 concentration and it was found lowest (3.2cm and 2.8cm) in M. uniflorum with underground part double distilled water extract at 400 mg mL-1. Biomass was recorded highest (1.97 g/100cm2) in Z. mays in aerial part extract and lowest (0.83 g/100 cm2) in horse gram in underground part extract at concentration of 400mg mL–1 with double distilled water extract. In methanol, both aerial and underground part extracts, the germination observed only at 1mg mL-1 concentration.