Charlet Laurence D, Aiken Robert M, Meyer Ron F, Gebre-Amlak Assefa
USDA-ARS Northern Crop Science Laboratory, Fargo, ND 58105-5677, USA.
J Econ Entomol. 2007 Aug;100(4):1248-57. doi: 10.1603/0022-0493(2007)100[1248:iocpda]2.0.co;2.
The guild of stem-infesting insect pests of sunflower, Helianthus annuus L., within the central Plains is a concern to producers chiefly due to losses caused by plant lodging from the sunflower stem weevil, Cylindrocopturus adspersus (LeConte) (Coleoptera: Curculionidae), and Dectes texanus texanus LeConte (Coleoptera: Cerambycidae). The incidence of a root boring moth, Pelochrista womonana (Kearfott) (Lepidoptera: Tortricidae), also has increased. Experiments were conducted in three locations in Colorado and Kansas during 2001-2003 to investigate the potential of combining planting date and foliar and seed treatment insecticide applications to lower insect stalk densities of these three pests. The impact of these strategies on weevil larval parasitoids also was studied. Eight sunflower stem weevil larval parasitoid species were identified. All were Hymenoptera and included the following (relative composition in parentheses): Nealiolus curculionis (Fitch) (42.6%), Nealiolus collaris (Brues) (3.2%) (Braconidae), Quadrastichus ainsliei Gahan (4.2%) (Eulophidae), Eurytoma tylodermatis Ashmead (13.1%) (Eurytomidae), Neocatolaccus tylodermae (Ashmead) (33.7%), Chlorocytus sp. (1.6%), Pteromalus sp. (0.5%) (Pteromalidae), and Eupelmus sp. (1.0%) (Eupelmidae). The results from this 3-yr study revealed that chemical control was often reliable in protecting the sunflower crop from stem pests and was relatively insensitive to application timing. Although results in some cases were mixed, overall, delayed planting can be a reliable and effective management tool for growers in the central Plains to use in reducing stem-infesting pest densities in sunflower stalks. Chemical control and planting date were compatible with natural mortality contributed by C. adspersus larval parasitoids.
在中原地区，向日葵（Helianthus annuus L.）的茎部害虫群体是生产者关注的问题，主要是因为向日葵茎象甲（Cylindrocopturus adspersus (LeConte)，鞘翅目：象甲科）和德克萨斯茎象甲（Dectes texanus texanus LeConte，鞘翅目：天牛科）导致的植株倒伏造成了损失。一种根蛀蛾Pelochrista womonana (Kearfott)（鳞翅目：卷蛾科）的发生率也有所增加。2001年至2003年期间，在科罗拉多州和堪萨斯州的三个地点进行了试验，以研究结合播种日期以及叶面和种子处理杀虫剂应用来降低这三种害虫在茎部的密度的潜力。还研究了这些策略对象甲幼虫寄生蜂的影响。鉴定出了8种向日葵茎象甲幼虫寄生蜂物种。它们均为膜翅目，包括以下种类（括号内为相对占比）：Curculionis象甲新蜂（Nealiolus curculionis (Fitch)）（42.6%）、Collaris象甲新蜂（Nealiolus collaris (Brues)）（3.2%）（茧蜂科）、Ainsliei四节小蜂（Quadrastichus ainsliei Gahan）（4.2%）（釉小蜂科）、Tylodermatis广肩小蜂（Eurytoma tylodermatis Ashmead）（13.1%）（广肩小蜂科）、Tylodermae新猫瘤节小蜂（Neocatolaccus tylodermae (Ashmead)）（33.7%）、Chlorocytus属物种（1.6%）、Pteromalus属物种（0.5%）（金小蜂科）和Eupelmus属物种（1.0%）（旋小蜂科）。这项为期3年的研究结果表明，化学防治在保护向日葵作物免受茎部害虫侵害方面通常是可靠的，并且对施药时间相对不敏感。尽管在某些情况下结果好坏参半，但总体而言，推迟播种对于中原地区的种植者来说是一种可靠且有效的管理手段，可用于降低向日葵茎部害虫的密度。化学防治和播种日期与向日葵茎象甲幼虫寄生蜂造成的自然死亡率是相容的。
