ALLELOPATHIC EFFECT OF A WEED SPECIES, CYPERUS ROTUNDUS L. AND CLEOME VISCOSA L. ON GROWTH AND DEVELOPMENT OF BLACK GRAM (VIGNA MUNGO (L.) HEPPER.)

Abstract

The present study was aimed to investigate the allelopathic influence of two weed species Cyperus rotundus L. and Cleome viscosa L. against the growth of Black gram (Vigna mungo (L.) Hepper). Aqueous extracts (5%, 10%, 25%, 50%, 75% and 100% concentrations) of whole plants of C. rotundus and C. viscosa were employed to investigate their influence on the germination and seedling growth of the black gram. The aqueous whole plants extracts ( from 5% to 100% concentrations) of C. rotundus and C. viscosa exhibited an inhibitory effects on all the parameters employed in the germination percentage, root and shoot growth, fresh and dry weight, content of chlorophyll, starch, sugar and protein contents of Black gram over control. The extracts of both the weeds caused a minimum inhibition on germination and seedling growth of Black gram at 5% concentration and the intensity of inhibition increased when increased extract concentrations. The aqueous extracts of C. rotundus and C. viscosa showed an inhibitory effect on Black gram but their effect was more severe on black gram by the extract treatments of C. rotundus than that of C. viscosa.