Tree species as a potential source of bio-herbicides for controlling Parthenium hysterophorus L

To assess the herbicidal potential of Eugenia jambolana Lam., Ricinus communis L., Ziziphus jujuba L. and Ziziphus mauritiana L. against noxious weed Parthenium hysterophorus L., germination bioassay using their 1%, 2%, 3%, 4% and 5% (w/v) and seedling growth bioassay using their 5% (w/v) (on dry weight basis) aqueous leaf extracts (ALE) were conducted. ALE of R. communis showed maximum reductions in germination percentage (79%), germination index (89%) and seedling biomass (88%) as well as maximum delays in mean germination time (211%) and time to 50% germination (265%) of parthenium whereas maximum reductions in its seedling length (47%) and seedling vigour index (97%) were shown by Z. mauritiana. Reciprocal dose-response relationship by probit regression analysis revealed that LC50 values of R. communis and Z. mauritiana are 1.04% and 1.44%, respectively. Therefore, R. communis and Z. mauritiana are potential sources of bio-herbicides against this weed.