Department of Entomology, University of California, 92521, Riverside, California.
J Chem Ecol. 1989 Sep;15(9):2379-90. doi: 10.1007/BF01012089.
Phaseolus lunatus L. (Henderson Bush lima beans) were exposed to 2 hr acidic fogs with 2.5∶1.0 (v/v) nitrogen-sulfur ratio typical of the west coast of the United States. Fogs with pH values of 2.0 (P < 0.01,t tests), 2.5 (P < 0.05), or 3.0 (P < 0.01) increased percent total nitrogen (dry weight) of foliage as compared to plants subjected to control fogs with a pH of 6.3-6.5. Fresh weight concentrations of soluble protein and certain free amino acid concentrations were increased by plant exposure to acidic fogs with a pH of 2.5 (t tests,P < 0.05). Concentrations of free amino acids considered essential for insect growth, as well as nonessential and total free amino acids were not significantly affected by any treatment (P > 0.05,t test). Water content (%) of foliage was not changed significantly (P > 0.05,t test) by exposure to any of the fogs.Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae) larvae ate significantly more foliage and gained significantly more weight on plants treated with 3.0 pH fogs (P < 0.01,t test). Several potential explanations are offered for the lack of significant weight gain by larvae on plants in which soluble protein levels, free amino acid concentrations, or percent total nitrogen contents were enhanced by acidic fogs with a pH of 2.5 and 2.0. No larval feeding preference was detected for foliage exposed to acidic versus control fogs, and no significant differences were detected in percent survival ofT. ni eggs exposed to acidic or control fogs. Some implications of acidic fogs for population dynamics ofT. ni are discussed.
菜豆（Henderson Bush 利马豆）暴露于具有美国西海岸典型的 2.5∶1.0（v/v）氮-硫比的 2 小时酸性雾中。与 pH 值为 6.3-6.5 的对照雾相比，pH 值为 2.0（P<0.01，t 检验）、2.5（P<0.05）或 3.0（P<0.01）的雾显著增加了叶片的总氮含量（干重）。暴露于 pH 值为 2.5 的酸性雾会使植物中可溶性蛋白质和某些游离氨基酸的浓度增加（t 检验，P<0.05）。对于昆虫生长至关重要的游离氨基酸浓度，以及非必需和总游离氨基酸浓度，没有受到任何处理的显著影响（P>0.05，t 检验）。叶片的水分含量（%）没有因暴露于任何雾中而显著改变（P>0.05，t 检验）。斜纹夜蛾（Hübner）（鳞翅目：夜蛾科）幼虫在 pH 值为 3.0 的雾处理的植物上明显吃得更多，体重明显增加（P<0.01，t 检验）。对于叶片中可溶性蛋白质水平、游离氨基酸浓度或总氮含量因 pH 值为 2.5 和 2.0 的酸性雾而增强的植物中，幼虫体重没有显著增加，提供了几种可能的解释。对于暴露于酸性雾和对照雾的叶片，幼虫没有表现出明显的取食偏好，也没有检测到暴露于酸性或对照雾中的斜纹夜蛾卵的存活率有显著差异。讨论了酸性雾对斜纹夜蛾种群动态的一些影响。
