Northern, Diabrotica barberi Smith & Lawrence, and western, D. virgifera virgifera LeConte, corn rootworms are major economic pests of corn, Zea mays L., in the United States. This research was conducted to determine the geographic distribution, abundance, and species composition of Diabrotica species in North Dakota, and to compare effectiveness of unbaited green Scentry™ Multigard and unbaited yellow Pherocon® AM/NB sticky traps for monitoring. Fifty‐one corn fields were monitored using traps from July through October of the 2013, 2014, and 2015 growing seasons for rootworm beetle activity. The overall species composition was 61% D. barberi and 39% D. v. virgifera. Both species were frequently captured, and the highest densities (i.e. >10 beetles per trap per week) were found in southeastern North Dakota. Low densities (i.e. <0.1 beetles per trap per week) of D. barberi were found in areas further north, but no D. v. virgifera were captured in those fields. The two different coloured sticky traps were not significantly different across 38 sites for D. barberi and across 21 sites for D. v. virgifera. However, green Scentry™ Multigard traps captured more D. barberi beetles than yellow Pherocon® AM/NB traps at 68% of the 38 fields. In contrast, the yellow Pherocon® AM/NB traps captured more D. v. virgifera beetles at 57% of the 21 fields. Findings also indicated that, although D. barberi was the predominant species in surveyed fields, populations rarely reached the economic threshold. Our study observed that economic populations of corn rootworms were infrequent among the field sites trapped in North Dakota. As a result, producers should scout fields regularly for corn rootworm populations levels to make sound pest management decisions. This knowledge can enable producers to effectively protect their crop when control is economically justified, and the information can also provide input cost savings when populations do not warrant control efforts.

中文翻译：

---

北达科他州玉米根虫调查和两个粘性陷阱的比较

北部的 Diabrotica barberi Smith & Lawrence 和西部的 D. virgifera virgifera LeConte，玉米根虫是美国玉米 Zea mays L. 的主要经济害虫。本研究旨在确定北达科他州 Diabrotica 物种的地理分布、丰度和物种组成，并比较无诱饵绿色 Scentry™ Multigard 和无诱饵黄色 Pherocon® AM/NB 粘性捕集器的监测效果。从 2013 年、2014 年和 2015 年生长季节的 7 月到 10 月，使用诱捕器监测了 51 个玉米田的根虫甲虫活动。总体物种组成为 61% D. barberi 和 39% D. v. virgifera。这两种物种都经常被捕获，在北达科他州东南部发现的密度最高（即每个陷阱每周 >10 只甲虫）。低密度（即 <0. 在更北的地区发现了 D. barberi 的每个陷阱每周 1 只甲虫，但在这些田地中没有捕获到 D. v. virgifera。两种不同颜色的粘性陷阱在 D. barberi 的 38 个站点和 D. v. virgifera 的 21 个站点之间没有显着差异。然而，在 38 个字段中，绿色 Scentry™ Multigard 陷阱比黄色 Pherocon® AM/NB 陷阱捕获了更多的 D. barberi 甲虫。相比之下，黄色 Pherocon® AM/NB 陷阱在 21 个田地中的 57% 捕获了更多 D. v. virgifera 甲虫。调查结果还表明，尽管 D. barberi 是调查领域的主要物种，但种群数量很少达到经济门槛。我们的研究观察到，在北达科他州被困的田间场地中，玉米根虫的经济种群并不常见。因此，生产者应定期对田地进行玉米根虫种群水平调查，以做出合理的害虫管理决策。当控制在经济上是合理的时，这些知识可以使生产者有效地保护他们的作物，当人口不需要控制时，这些信息还可以节省投入成本。