Department of Fruit Science, Punjab Agricultural University, Ludhiana, Punjab, India.
Department of Entomology, Michigan State University, East Lansing, MI.
J Econ Entomol. 2021 Feb 9;114(1):486-491. doi: 10.1093/jee/toaa271.
Spotted-wing drosophila (Drosophila suzukii, (Matsumura)) is an invasive vinegar fly that has become a serious threat to soft fruit crops. Monitoring for this pest is typically performed using drowning traps baited with live yeast cultures or fermentation volatile blends. Trapping programs using these compounds provide highly variable results across production systems, geographic regions, and growing seasons. Trap competition with fruit is one hypothesis for this inconsistency. This study evaluated the trapping efficiency of yeast and wine baits in the presence and absence of small quantities of host fruits in two binary-choice laboratory experiments. The first experiment evaluated trap capture in clear 946-ml traps with easily accessible water, apple pomace, blueberry, raspberry, strawberry, cherry, or grape as competitive influences. The second experiment evaluated the same competitors, but they were made less accessible. Recapture of flies in arenas containing competitive fruit was reduced by 64-88% when fruit was 'accessible' and from 0 to 51% when it was 'inaccessible' compared with arenas containing a water competitor. All fruit types provided statistically similar levels of trap interference. In the first experiment, yeast captured more flies compared with wine, whereas in the second experiment, wine captured more flies than yeast. Our results support the hypothesis that the presence of fruit or other reproductive resources will reduce trap captures and that this reduction is likely mediated by the relative accessibility of the fruit versus the trap. Thus, attempts to develop population estimates based on traps should incorporate fruit availability/accessibility.
有斑实蝇（Drosophila suzukii，(Matsumura))是一种入侵性的醋蝇，已成为软果作物的严重威胁。这种害虫的监测通常使用诱饵为活酵母培养物或发酵挥发性混合物的溺水陷阱进行。使用这些化合物的诱捕计划在生产系统、地理区域和生长季节之间提供高度可变的结果。陷阱与果实竞争是这种不一致性的一个假设。本研究在两个二元选择实验室实验中评估了酵母和葡萄酒诱饵在存在和不存在少量宿主果实的情况下的诱捕效率。第一个实验评估了在清澈的 946 毫升诱捕器中，在容易接触水、苹果渣、蓝莓、覆盆子、草莓、樱桃或葡萄作为竞争影响的情况下，诱捕器的捕获情况。第二个实验评估了相同的竞争对手，但它们的可及性降低了。在包含有竞争力的果实的竞技场中，与含有水竞争的竞技场相比，当果实“可接触”时，苍蝇的再捕获减少了 64-88%，而当果实“不可接触”时，苍蝇的再捕获减少了 0-51%。所有水果类型都提供了统计学上相似的陷阱干扰水平。在第一个实验中，酵母比葡萄酒捕获了更多的苍蝇，而在第二个实验中，葡萄酒比酵母捕获了更多的苍蝇。我们的结果支持了这样一种假设，即果实或其他繁殖资源的存在会降低诱捕器的捕获率，而这种降低很可能是由果实与诱捕器的相对可及性介导的。因此，试图根据诱捕器开发种群估计数时，应考虑果实的可用性/可及性。
