Eucosma giganteana (Riley) is a native specialist pest of silflower, Silphium integrifolium Michx., which is currently being domesticated as a perennial oilseeds crop. The larvae of this moth attack silflower capitula and root crowns, causing both seed damage and long-term degradation of plants. To determine methods to manage E. giganteana in silflower crop fields, we conducted a laboratory bioassay and 3 field experiments to assess the effects of a suite of organic, conventional, and mechanical treatments on E. giganteana mortality and colonization of flower heads. Pyrethroids (permethrin, cyfluthrin), chlorantraniliprole, and methoxyfenozide each had significant insecticidal effects on E. giganteana in at least 2 of the experiments conducted. Nematodes marginally increased larva mortality in the laboratory bioassay and could be further investigated as a soil-applied biological control. In 2 separate field experiments, trimming the top 15% of silflower plants to delay flowering did not alone reduce E. giganteana colonization of flower heads throughout the growing season. However, when trimming was paired with a single chlorantraniliprole application, colonization of capitula was reduced by 83% over untreated control plants. Collectively, these experiments provide evidence for several treatments that could be further tested and incorporated into an integrated pest management strategy for E. giganteana.

中文翻译：

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评估管理多年生油料作物 Silphium integrifolium（菊科：Heliantheae）中的 Eucosma giganteana（鳞翅目：Tortricidae）的有效机械和化学策略

Eucosma giganteana (Riley) 是银花 (Silphium integrifolium Michx.) 的本地专害虫，目前被驯化为多年生油籽作物。这种蛾的幼虫攻击银花头状花序和根冠，造成种子损坏和植物的长期退化。为了确定在银花作物田中管理巨桉的方法，我们进行了实验室生物测定和 3 次田间实验，以评估一系列有机、常规和机械处理对巨桉死亡率和花头定植的影响。在至少 2 个进行的实验中，拟除虫菊酯（氯菊酯、氟氯氰菊酯）、氯虫苯甲酰胺和甲氧虫酰肼均对巨桉具有显着的杀虫作用。在实验室生物测定中，线虫略微增加了幼虫死亡率，并且可以作为土壤应用的生物控制进一步研究。在 2 个独立的田间实验中，修剪银花植株顶部 15% 以延迟开花并不能单独减少整个生长季节中巨桉在花头的定殖。然而，当修剪与单次氯虫苯甲酰胺施用配合使用时，头状花序的定植比未经处理的对照植物减少了 83%。总的来说，这些实验为几种治疗方法提供了证据，可以进一步测试这些治疗方法并将其纳入巨桉害虫综合防治策略中。