Lai L C, Hua K H, Yang C C, Huang R N, Wu W J
Department of Entomology, National Taiwan University, No 27, Lane 113, Sec. 4, Roosevelt Rd., Taipei 10617, Taiwan.
Environ Entomol. 2009 Jun;38(3):879-84. doi: 10.1603/022.038.0342.
Solenopsis geminata (F.) was introduced into southern Taiwan decades ago and has continued to threaten the residents. Although the venom compositions of various fire ant species have been studied, the effects of environmental cues on the secretion pattern have received relatively little attention in an area with subtropical climate and high humidity, such as Taiwan. This study characterizes the effects of temperature and season on the venom compositions of S. geminata in Taiwan. Pure venom was sampled by using a microcapillary pipette and immersing the whole ant in hexane and subjected to gas chromatography-mass spectrometry analysis. The results showed that the ratio of cis C(11) to trans C(11) alkaloids in major workers was significantly higher than that in minor workers. No significant differences could be found in either the relative alkaloids content or the ratio of cis C(11) to trans C(11) alkaloids in venom of minor workers while rearing at four temperature conditions. Nevertheless, the ratio of cis C(11) to trans C(11) alkaloids in the venom of minor workers was the highest in spring and the lowest in winter. The results also showed that the body length, abdomen length, head length, head width, and venom volume differed significantly between major workers and minor workers of S. geminata. The venom volumes of these two castes were positively correlated with their body sizes.
双齿多刺蚁（红火蚁）几十年前被引入台湾南部，并且持续威胁着当地居民。尽管对各种火蚁物种的毒液成分已进行过研究，但在亚热带气候和高湿度地区（如台湾），环境线索对毒液分泌模式的影响相对较少受到关注。本研究描述了温度和季节对台湾双齿多刺蚁毒液成分的影响。通过使用微量毛细管移液器采集纯毒液，将整只蚂蚁浸入己烷中，然后进行气相色谱 - 质谱分析。结果表明，大兵蚁中顺式C(11)与反式C(11)生物碱的比例显著高于小兵蚁。在四种温度条件下饲养时，小兵蚁毒液中的相对生物碱含量或顺式C(11)与反式C(11)生物碱的比例均未发现显著差异。然而，小兵蚁毒液中顺式C(11)与反式C(11)生物碱的比例在春季最高，冬季最低。结果还表明，双齿多刺蚁的大兵蚁和小兵蚁在体长、腹长、头长、头宽和毒液量方面存在显著差异。这两个蚁群的毒液量与它们的体型呈正相关。
