PDF(Pubmed)
Abstract：
Tribolium castaneum and Rhyzopertha dominica are cosmopolitan, destructive postharvest pests. Although research has investigated how high densities of T. castaneum affect attraction to the aggregation pheromone by conspecifics, research into the behavioral response of both species to food cues after high density exposure has been lacking despite its importance to foraging ecology. Our goal was to manipulate and observe the effects of crowding on the behavioral response of both species to common food and pheromonal stimuli and to determine how the headspace emission patterns from grain differed under increasing densities. Densities of colonies for both species was altered (10-500 adults) on a fixed quantity of food (10 g of flour or whole wheat), then the behavioral response to common food and pheromonal cues was evaluated in a wind tunnel and release-recapture experiment, while volatiles were examined through gas chromatography coupled with mass spectrometry. Importantly, at least for T. castaneum, crowded conditions attenuate attraction to food-based stimuli, but not pheromonal stimuli. Crowding seemed to have no effect on R. dominica attraction to food and pheromonal stimuli in the wind tunnel, but exposure to high density cues did elicit 2.1-3.8-fold higher captures in traps. The relative composition and abundance of headspace volatiles emitted varied significantly with different densities of beetles and was also species-specific. Overall, our results have implications for expanding our understanding of the foraging ecology of two economically important pests.
摘要：
蓖麻和多米尼克是世界性的，破坏性的采后害虫。尽管研究已经研究了高密度的栗树如何通过特异性影响对聚集信息素的吸引力，尽管高密度暴露对觅食生态学很重要，但仍缺乏对这两种物种对食物线索的行为反应的研究。我们的目标是操纵和观察拥挤对两种物种对常见食物和信息素刺激的行为反应的影响，并确定在密度增加的情况下谷物的顶部空间发射模式如何不同。在固定数量的食物（10克面粉或全麦）上，两种物种的菌落密度都发生了变化（10-500只成虫），然后在风洞和释放-再捕获实验中评估对常见食物和信息素线索的行为反应，而挥发物通过气相色谱与质谱联用进行检测。重要的是,至少对于蓖麻,拥挤的条件减弱了对食物刺激的吸引力，但不是信息素刺激。拥挤似乎对风洞中的食物和信息素刺激没有影响。但是暴露于高密度线索确实引起了陷阱捕获的2.1-3.8倍。释放的顶空挥发物的相对组成和丰度随甲虫密度的不同而显着变化，并且也具有物种特异性。总的来说,我们的结果对于扩大我们对两种经济上重要的害虫的觅食生态的理解具有重要意义。
