Department of Entomology, University of Wisconsin - Madison, Madison, WI.
J Econ Entomol. 2019 Aug 3;112(4):1789-1797. doi: 10.1093/jee/toz102.
Drosophila suzukii (Matsumura) is an invasive species of vinegar fly that infests soft-skinned and stone fruits. Since its first detection in the United States, D. suzukii has become a prominent economic threat in fruit crop industries, particularly affecting caneberry and sweet cherry growers. This study examined the susceptibility of tart cherries (Prunus cerasus) to D. suzukii and sampled for larvae and adult D. suzukii during the tart cherry growing season. Four tart cherry cultivars (Montmorency, Balaton, Carmine Jewel, and Kántorjánosi) were tested at three different ripeness stages (unripe, ripening, and ripe), in no-choice laboratory bio-assays. Field monitoring and sampling revealed that first adult D. suzukii detection occurred on 16 June, and first field larval D. suzukii detection occurred on 28 July. Adult D. suzukii populations increased through late August, and high numbers of adults overlapped with the tart cherry harvest. Lab assays indicated that tart cherry cultivars generally became more susceptible to D. suzukii as they ripened. As the fruit developed, °Brix (sugar content) increased and firmness generally decreased. Tart cherry °Brix and firmness were not correlated with the number of D. suzukii eggs per gram of fruit, but showed a significant interaction effect with the number of larvae and adults per gram of fruit. This study shows that tart cherries are largely not susceptible to D. suzukii when unripe and become susceptible as soon as the fruits change color, suggesting that fruits should be protected as soon as they begin to ripen and D. suzukii populations begin to rise.
果实蝇（Drosophila suzukii）是一种入侵性的醋蝇，会侵害肉质柔软的核果和浆果。自首次在美国被发现以来，果实蝇已成为水果产业的主要经济威胁，尤其对蔓越莓和甜樱桃种植者造成影响。本研究调查了酸樱桃（Prunus cerasus）对果实蝇的易感性，并在酸樱桃生长季节对幼虫和成虫进行了采样。在无选择的实验室生物测定中，测试了四个酸樱桃品种（Montmorency、Balaton、Carmine Jewel 和 Kántorjánosi）在三个不同成熟阶段（未成熟、成熟和成熟）的易感性。田间监测和采样显示，第一只成虫果实蝇于 6 月 16 日首次被发现，第一只田间幼虫果实蝇于 7 月 28 日首次被发现。成虫果实蝇种群在 8 月底增加，并出现大量成虫与酸樱桃收获期重叠。实验室检测表明，随着果实的成熟，酸樱桃品种对果实蝇的易感性通常会增加。随着果实的发育，糖度（含糖量）增加，硬度通常降低。酸樱桃的糖度和硬度与每克果实中的果实蝇卵数没有相关性，但与每克果实中的幼虫和成虫数有显著的相互作用效应。本研究表明，酸樱桃在未成熟时对果实蝇基本没有易感性，一旦果实变色就变得易感，这表明果实应该在开始成熟和果实蝇种群开始上升时就加以保护。
