Effect of leaf litter of poplar on Phalaris minor weed

摘要

The effect of aqueous extracts of poplar (Populus deltoides) trees was studied on germination and growth of Phalaris minor, a major weed of wheat crop. The extracts from partially decomposed leaves of poplar significantly reduced the germination and growth of Phalaris minor as compared to control. The magnitude of reduction was greater during the initial stages of decomposition. Irrespective of decomposition stage, intensity of inhibitory effect increased with higher concentration of extract. The extract of soil up to a distance of 3 m from the tree base of three years old plantation, also significantly decreased the germination and seedling growth of P. minor, which further intensified and extended up to 6 m in the fourth year. Thus, it can be inferred that presence of allelochemicals in leaves and in soil underneath the poplar tree reduced the germination as well as suppressed the growth of P. minor and effect was more pronounced with advancement of tree age.