Department of Entomology, University of California, 92521, Riverside, California.
J Chem Ecol. 1982 Feb;8(2):517-26. doi: 10.1007/BF00987799.
An extract of the hydrophyteMyriophyllum spicatum L. was found to be toxic to first- and fourth-instar larvae of the mosquitoes,Culex quinquefasciatus Say,Culex tarsalis Coquillett,Culiseta incidens (Thomson),Aedes aegypti L., and chironomid midges in the laboratory. When first-stage larvae were exposed to the extract, the lowest concentration (6.4 mg extract/100 ml H2O) produced 86,60, and 48% mortality inC. incidens, C. quinquefasciatus, andA. aegypti, respectively. Higher concentrations caused 100% mortality in both first and fourth instars (63.75 mg/100 ml H2O or more). In general, the biocidal activity of the extract was found to be similar when first- and fourth-stage larvae were exposed. Some mortality in the successive pupal and adult stages was observed when fourth-stage larvae were exposed to the extract, but mortality occurred only in the various larval instars when first instars were exposed. Among the chironomids,Tanytarsus spp. was more tolerant to the extract thanChironomus spp. In addition to the biocidal activity against immature mosquitoes, the extract was found to show a unique activity acting as an attractant to both sexes of adultC. quinquefasciatus andA. aegypti. The response elicited inA. aegypti appeared to be somewhat higher than that inC. quinquefasciatus. In general, the percentage of males responding to water treated with the extract was higher than that of the females. The extract at higher concentrations seemed to show some repellency at the outset to both species, but induced positive responses later on.
水生物竹叶眼子菜提取物对实验室条件下的一龄和四龄蚊虫幼虫，如致倦库蚊、三带喙库蚊、骚扰阿蚊和库蠓具有毒性。当一龄幼虫接触到提取物时，C. incidens、C. quinquefasciatus 和 A. aegypti 的最低浓度（6.4 mg 提取物/100 ml H2O）分别产生 86%、60%和 48%的死亡率。更高的浓度会导致一龄和四龄幼虫 100%死亡（63.75 mg/100 ml H2O 或更高）。一般来说，一龄和四龄幼虫接触提取物时，其生物杀灭活性相似。当四龄幼虫接触提取物时，观察到连续蛹和成虫阶段的一些死亡，但当一龄幼虫接触提取物时，只有各种幼虫阶段发生死亡。在摇蚊中，Tanytarsus spp. 比 Chironomus spp. 对提取物更具耐受性。除了对幼蚊的生物杀灭活性外，提取物还被发现具有一种独特的活性，作为成蚊 C. quinquefasciatus 和 A. aegypti 的引诱剂。在 A. aegypti 中引起的反应似乎略高于 C. quinquefasciatus。一般来说，对水进行处理后，雄性对提取物的反应百分比高于雌性。在较高浓度下，提取物起初似乎对两种物种都有一定的驱避作用，但后来会引起积极的反应。
