Trécé Incorporated, Adair, OK.
Department of Entomology and Plant Pathology, Oklahoma State University, Stillwater, OK.
J Econ Entomol. 2020 Aug 13;113(4):1990-1998. doi: 10.1093/jee/toaa064.
The sugarcane aphid (Melanaphis sacchari Zehntner) is a significant economic pest of grain sorghum (Sorghum bicolor (L.) Moench) in the Southern United States. Current nominal and research-based economic thresholds are based on estimates of mean aphids per leaf. Because enumerating aphids per leaf is potentially time consuming, binomial sequential sampling plans for M. sacchari were developed that allow users to quickly classify the economic status of field populations and determine when an economic threshold has been exceeded. During 2016 and 2017, counts of M. sacchari were recorded from 281 sampling events in 140 sorghum fields located in six states (Oklahoma, Kansas, Texas, Arkansas, Louisiana, Mississippi) . Regression analysis was used to describe the relationships between the mean M. sacchari density per two-leaf sample and proportion of plants infested with one or more aphids. Tally thresholds of T50 and T100 aphids per two-leaf sample were selected based on goodness of fit and practicality. Stop lines for both tally thresholds were developed for selected economic thresholds using Wald's sequential probability ratio test. Model validations using an additional 48 fields demonstrated that reliable classification decisions could be made with an average of 11 samples regardless of location. This sampling system, when adopted, can allow users to easily and rapidly determine when M. sacchari infestations need to be treated.
甘蔗绵蚜（Melanaphis sacchari Zehntner）是美国南部高粱（Sorghum bicolor (L.) Moench）的一种重要经济害虫。目前的名义和基于研究的经济阈值是基于每叶平均蚜虫估计数。由于每叶蚜虫的计数可能很耗时，因此开发了甘蔗绵蚜的二项式序贯抽样计划，允许用户快速分类田间种群的经济状况，并确定何时超过经济阈值。在 2016 年和 2017 年，从六个州（俄克拉荷马州、堪萨斯州、德克萨斯州、阿肯色州、路易斯安那州和密西西比州）的 140 个高粱田的 281 次采样事件中记录了甘蔗绵蚜的计数。回归分析用于描述每两叶样本中平均甘蔗绵蚜密度与受一种或多种蚜虫侵染的植物比例之间的关系。根据拟合度和实用性，选择了每两叶样本中 T50 和 T100 蚜虫的计数阈值。使用 Wald 的序贯概率比检验为选定的经济阈值开发了这两个计数阈值的停止线。使用另外 48 个田块的模型验证表明，无论位置如何，平均 11 个样本就可以做出可靠的分类决策。采用这种抽样系统，可以让用户轻松快速地确定何时需要对甘蔗绵蚜进行处理。
