抄録
Allelopathic potential by a submerged macrophyte Potamogeton pusillus against Microcystis aeruginosa in actual ponds was evaluated. The culture filtrate of P. pusillus inhibited the growth of M. aeruginosa, suggesting that P. pusillus released allelochemicals. For the evaluation of allelopathic potential in actual ponds, water samples collected in and out of vegetated mesocosm were examined by a novel bioassay method. Also, allelopathic potential of water obtained from vegetated and unvegetated mesocosm was compared. As a result, water in P. pusillus-vegetated mesocosm showed an obvious growth-inhibiting effect on M. aeruginosa but not in unvegetated mesocosm and out of mesocosm. The water obtained from two ponds, Yamanokami and Bessho Pond, confirmed these effects. The results indicated allelopathic effect by P. pusillus community worked in actual ponds or lakes and the effect lasted as long as P. pusillus inhabited.
