Investigation of Allelopathic Potentiality of the Himalyan Lichen Parmelia Reticulata Tayl. Against Phalaris Minor Retz.

Abstract Allelopathic potentiality of hexane, ethyl acetate and methanol extracts of the Himalyan lichen, Parmelia reticulate Taylor, at different concentrations (50, 25 and 12.5 μg ml -1 ) was studied on germination and early seedling growth of highly devastating weed Phalaris minor . The experiments were carried out in portray maintained in natural environment. Current investigation has revealed concentration dependent allelopathic phenomenon of the lichen extracts on P. minor . Hexane and ethyl acetate extracts at 50 μg ml -1 exhibited maximum detrimental effect on seed germination (56% as compared to control i.e. 90%). Hexane extract at 50 μg ml -1 showed maximum inhibition of early seedling growths, determined in terms of shoot and root lengths of the test weed. It reduced shoot and root lengths to 2.5cm (control 10.7 cm) and 0.9 cm (control 3.4cm) respectively, indicating semipolar nature of constituents responsible for bioactivity.