Allelopathic potential of the rice field weed, water primrose Ludwigia adscendens (L.) leaf, stem and leaf+stem on germination, root and shoot length, seedling vigour and vigour index of the greengram [Vigna radiate (L.), cv.KB-54], was investigated in the laboratory. The different concentrations (e.g. 5, 10, 20, 40, 60, 80 and 100%) of the aqueous extract of leaf stem and leaf+stem of the weed parts were applied separately on greengram seeds in petri dishes lined with filter paper. The per cent of germination decreased from 4-32%, 2–23% and 7-36%, and root length and shoot length of the greengram also decreased from 0.01–2.04 cm, 0.02–1.96 cm and 0.07–2.08, and 0.818–1.575 cm, 0.785–1.567 and 0.83–1.64 cm for increased concentrations of the weed leaf, stem and leaf+stem extracts over control, respectively. The seedling vigour and vigour index of the greengram were decreased considerably from 13.32–237.6, 8.14–221.9 and 28.14–244.36, and 85.68–166.62, 80.65–164.44 and 90.21–171.92 with increased concentrations of different parts of aqueous extract of the weed over control, respectively.
Ludwigia adscendens, Vigna radiate, Allelopathy
