Chemical Ecology, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, SE-230 53, Alnarp, Sweden.
J Chem Ecol. 2011 Aug;37(8):899-911. doi: 10.1007/s10886-011-9995-3. Epub 2011 Jul 13.
Orientation for insects in olfactory landscapes with high semiochemical diversity may be a challenging task. The partitioning of odor plumes into filaments that are interspersed with pockets of 'clean air' may help filament discrimination and upwind flight to attractive sources in the face of inhibitory signals. We studied the effect of distance between odor sources on trap catches of the beetle, Ips typographus, and the moth, Spodoptera littoralis. Insects were tested both to spatially separated pheromone components [cis-verbenol and 2-methyl-3-buten-2-ol for Ips; (Z,E)-9,11-tetradecadienyl acetate and (Z,E)-9,12-tetradecadienyl acetate for Spodoptera], and to separated pheromone and anti-attractant sources [non-host volatile (NHV) blend for Ips; (Z)-9-tetradecenyl acetate for Spodoptera]. Trap catch data were complemented with simulations of plume structure and plume overlap from two separated sources using a photo ionization detector and soap bubble generators. Trap catches of the beetle and the moth were both affected when odor sources in the respective traps were increasingly separated. However, this effect on trap catch occurred at smaller (roughly by an order of magnitude) odor source separation distances for the moth than for the beetle. This may reflect differences between the respective olfactory systems and central processing. For both species, the changes in trap catches in response to separation of pheromone components occurred at similar spacing distances as for separation of pheromone and anti-attractant sources. Overlap between two simulated plumes depended on distance between the two sources. In addition, the number of detected filaments and their concentration decreased with downwind distance. This implies that the response to separated odor sources in the two species might take place under different olfactory conditions. Deploying multiple sources of anti-attractant around a pheromone trap indicated long-distance (meter scale) effects of NHV on the beetle and a potential use for NHV in forest protection.
在具有高信息素多样性的嗅觉景观中，昆虫的定向可能是一项具有挑战性的任务。将气味羽流分割成丝状结构，这些丝状结构与“清洁空气”的口袋交错排列，可能有助于丝状结构的辨别，并在面对抑制信号时向上风向的有吸引力的源飞行。我们研究了气味源之间的距离对甲虫 Ips typographus 和飞蛾 Spodoptera littoralis 的诱捕器捕获的影响。我们分别对空间分离的信息素成分（顺式马鞭草烯醇和 2-甲基-3-丁烯-2-醇用于 Ips；乙酸（Z，E）-9，11-十四碳二烯酯和乙酸（Z，E）-9，12-十四碳二烯酯用于 Spodoptera）和分离的信息素和驱避剂源（非寄主挥发性混合物用于 Ips；乙酸（Z）-9-十四碳烯酯用于 Spodoptera）对昆虫进行了测试。利用光离子化检测器和肥皂泡发生器，从两个分离的源模拟羽流结构和羽流重叠，补充了诱捕器捕获的数据。当各自诱捕器中的气味源逐渐分离时，甲虫和飞蛾的诱捕器捕获都受到了影响。然而，这种对诱捕器捕获的影响在飞蛾中比在甲虫中发生在更小（大致数量级）的气味源分离距离处。这可能反映了它们各自的嗅觉系统和中枢处理之间的差异。对于这两个物种，对分离信息素成分的反应引起的诱捕器捕获的变化与分离信息素和驱避剂源的变化发生在相似的间隔距离。两个模拟羽流之间的重叠取决于两个源之间的距离。此外，检测到的丝的数量及其浓度随着顺风距离的增加而降低。这意味着这两个物种对分离的气味源的反应可能在不同的嗅觉条件下发生。在信息素诱捕器周围部署多个驱避剂源表明，非寄主挥发性混合物对甲虫具有长距离（米级）效应，并可能在森林保护中用于 NHV。
