Abstract
Large blooms of Nomura's jellyfish (Nemopilema nomurai Kishinoue) have recently observed in the Japan Sea, and caused serious damage to fisheries. It may be worthwhile to develop beneficial uses the jellyfish. We investigated the growth inhibitory activity of the jellyfish on the growth and emergence of weeds under laboratory and field conditions. Aqueous methanol extracts of the jellyfish inhibited the seedling growth of timothy (Phleum pratense L.), ryegrass (Lolium multiflorum Lam.) and barnyardgrass (Echinochloa crus-galli (L.) Beauv.) in the concentration dependent manner under a laboratory condition. Dried jellyfish incorporated into paddy field also inhibited weed emergence during rice (Oryza sativa cv. Hinohikari) cultivation. Therefore, the jellyfish may potentially be useful as soil additive materials to control weeds in the sustainable agriculture.
