Preliminary studies on allelopathic potential in rice

Experiments of allelopathic potential in six lines of rice indicated that the order inhibiting the barnyardgrass growth was “Woo Co Chin Yu”>“Kouketsumuchi”>“AC1423”>“CN-15”>“Taichung Native 1”>“YH-1”.Increasing the extract concentrations might cause higher inhibitory effect on the barnyardgrass. It also indicated that the phytotoxicity was density-dependent,showing that the inhibitory effect decreased with the increases of the weed density.Such a result was contrary to the effect of resource competition.