Opit G P, Throne J E, Flinn P W
USDA-ARS Grain Marketing and Production Research Center, 1515 College Ave., Manhattan, KS 66502-2736, USA.
J Econ Entomol. 2009 Aug;102(4):1714-22. doi: 10.1603/029.102.0440.
Psocids are an emerging problem in grain storage, handling, and processing facilities in the United States. We used data from two steel bins each containing 32.6 metric tonnes of wheat, Triticum aestivum L., to develop sampling plans for Liposcelis entomophila (Enderlein), Liposcelis decolor (Pearman) (both Psocoptera: Liposcelididae), and a mixture of the two species. Taylor's coefficients a (a sampling factor) and b (an index of aggregation) for these pests were calculated and incorporated into sampling protocols to improve accuracy. The optimal binomial sample sizes for estimating populations of these psocids at densities of < 25 psocids per refuge were large; therefore, we recommend the use of numerical sampling within this range of densities. Numerical sampling of L. entomophila and L. decolor at densities of < 25 psocids per refuge should not be too laborious given the low psocid numbers involved; we recommend using 10 refuges per bin. For presence-absence sampling of L. entomophila or L. decolor, 20 refuges per bin should be used at densities of 25-100 psocids per refuge. The sampling plans we have developed based on the use of cardboard refuges are convenient for use in steel bins containing wheat because they are inexpensive, provide a rapid assessment of psocid population incidence, and are easy to implement. These sampling plans can be used to monitor populations of and the efficacy of management strategies used against L. entomophila and L. decolor.
书虱是美国粮食储存、处理和加工设施中出现的一个新问题。我们使用了两个钢仓的数据，每个钢仓装有32.6公吨小麦（普通小麦），以制定嗜卷书虱（恩德勒林）、无色书虱（皮尔逊）（均属于啮目：书虱科）以及这两个物种混合物的抽样计划。计算了这些害虫的泰勒系数a（一个抽样因子）和b（聚集指数），并将其纳入抽样方案以提高准确性。在每个避难所书虱密度<25只时，估计这些书虱种群数量的最佳二项式样本量很大；因此，我们建议在这个密度范围内使用数值抽样。鉴于所涉及的书虱数量较少，在每个避难所书虱密度<25只时，对嗜卷书虱和无色书虱进行数值抽样应该不会太费力；我们建议每个仓使用10个避难所。对于嗜卷书虱或无色书虱的有无抽样，在每个避难所书虱密度为25 - 100只时，每个仓应使用20个避难所。我们基于使用硬纸板避难所制定的抽样计划便于在装有小麦的钢仓中使用，因为它们价格低廉，能快速评估书虱种群发生率，且易于实施。这些抽样计划可用于监测嗜卷书虱和无色书虱的种群数量以及针对它们所采用管理策略的效果。
