Allelopathic effect of some plants on morphological attributes of invasive alien weed: Malachra capitata (L.)L.

Vitex negundo L. [Verbenaceae] and Ricinus communis L. [Euphorbiaceae], are especially well known for their industrial, pharmacological, and toxicological properties, but to date very little is known about their allelopathic potential. Hence the present study was conducted to evaluate their allelopathic perspectives on morphological characters of invasive alien weed Malachra capitata [L.]L. Various concentrations [T1=5%, T2=10%, T3=15% and T=20%] of leaf leachates of selected plants were used as spray to test their effect on pot culture of test species. Results of present study indicated that the growth of plant was significantly inhibited in Malachra at all concentration of aqueous leaf leachates of selected plants when compared to control [T0].  Length of root and shoot, number of flowers, fruits and seeds of the weed was reduced with the increase in leaf leachates concentration. T1 of R. communis was least effective on root length. Branching was totally inhibited except for T1 of V. negundo. Dry weight and fresh weight of the weed were also negatively affected by aqueous leaf leachates of both the plants. Although results were significant at P<0.05 level, few parameters were not found significant.