Department of Chemistry and Biochemistry and Department of Biological Sciences, University of Southern Mississippi, 39406, Hattiesburg, Mississippi.
J Chem Ecol. 1991 Apr;17(4):707-14. doi: 10.1007/BF00994194.
Aqueous extracts ofNuphar lutea (L.) Sibth. & Sm. leaves (blades plus petioles) and roots plus rhizomes were tested for allelopathic activity using lettuce seedling andLemna minor L. assay systems. The 12.5, 25, 125, and 250 parts per thousand (ppt) treatments of both extracts killed the lettuce seedlings. At 2.5 ppt of extract, radicle growth of lettuce was 29% of the control for leaves and 31% of the control for roots plus rhizomes.Lemna minor frond number was reduced to 34% of the control by the 25 ppt leaf extract and to 43% of the control by the 25 ppt roots plus rhizomes extract.L. minor was killed by concentrations of 125 ppt and above of both plant part extracts. As expected, the frond number and total chlorophyll content measured by theL. minor assay were highly correlated. Osmotic potentials below 143 mOsmol/kg had no influence onL. minor growth. Neither the osmotic potential nor the pH of the undiluted extracts ofN. lutea were in the range known to influence the growth of either lettuce seedlings orL. minor. Nuphar lutea extracts were many times more inhibitory than 16 other hydrophytes we previously examined.
水莕菜（Nymphoides peltatum）叶（叶片加叶柄）和根及根茎的水提取物，采用生菜幼苗和浮萍（Lemna minor）测定系统，测试了它们的化感活性。两种提取物的 12.5、25、125 和 250 千分比浓度（ppt）处理均能杀死生菜幼苗。在 2.5 ppt 的提取物中，生菜的胚根生长为对照的 29%，根及根茎为对照的 31%。浮萍的叶片提取物在 25 ppt 时，浮萍的叶数减少到对照的 34%，根及根茎提取物在 25 ppt 时减少到对照的 43%。两种植物部分提取物的浓度为 125 ppt 及以上时，浮萍就会被杀死。正如预期的那样，浮萍测定中测量的叶数和总叶绿素含量高度相关。渗透势低于 143 mOsmol/kg 对浮萍的生长没有影响。水莕菜未稀释提取物的渗透势和 pH 值都不在已知会影响生菜幼苗或浮萍生长的范围内。水莕菜提取物的抑制作用比我们之前检查的 16 种其他水生植物高出许多倍。
