Allelopathic influence of a sacred grove tree species, Canthium dicoccum on seed germination and growth of green gram, Vigna radiata

摘要

We investigated the nature of allelopathic influence of a dominant sacred grove tree, Canthium dicoccum on Vigna radiata by treating the green gram seeds and seedlings with 0, 1.0, 2.5 and 5% concentrations of the aqueous leaf extract Germination and seedling growth (length, and biomass of shoot, root and plant)was inhibited by all concentrations. The lateral root development was decreased and was concentration dependant. Though the number of leaves was not reduced, the size and specific leaf area were significantly reduced suggesting a morphogenetic retardation. Nodulation were also adversely affected by the treatments. Besides nodule number and size, the activity of nitrate reductase was also inhibited. Preliminary chemical group tests revealed the presence of amides, acids and phenols in the leaf extract. Our data demonstrate that the inhibitory potential of the C.dicoccum extract during seed germination and early plant growth phase of green gram. The adverse impacts on events of nitrogen metabolism are a cause of concern from the food security viewpoint.