Athanassiou Christos G, Kavallieratos Nickolas G, Economou Leonidas P, Dimizas Constantin B, Vayias Basileios J, Tomanović Snezana, Milutinović Marija
Laboratory of Agricultural Zoology and Entomology, Agricultural University of Athens, 75 Iera Odos, 11855 Athens, Attica, Greece.
J Econ Entomol. 2005 Aug;98(4):1404-12. doi: 10.1603/0022-0493-98.4.1404.
The insecticidal and residual efficacy of three diatomaceous earth (DE) formulations, Insecto, PyriSec, and SilicoSec, against Sitophilus oryzae (L.) on barley and wheat was assessed. For this purpose, 4-kg lots of barley and wheat were treated with the above-mentioned DE formulations, in three dose rates (0.75, 1, and 1.5 g/kg grain) and stored at 26 degrees C. Samples of these lots were taken at the day of storage, and every 45 d, until the completion of a 450-d period of storage. Bioassays were conducted by exposing S. oryzae adults to these samples, at 26 degrees C and 57% RH. In these bioassays, the DE efficacy was evaluated by recording adult mortality after 24 h, 48 h, 7 d, and 14 d of exposure on the treated grains. After the 14-d count, all adults were removed, and the samples were left at the same conditions for an additional 45 d, to evaluate the capacity for progeny production in the treated grains. Adult mortality after 14 d of exposure was exponentially decreased with time. During the first 270 d of storage, mortality was > 90%, and progeny production was < 1 adult per sample, whereas after 270 d a gradual decrease in adult mortality occurred, with a resulting increase in progeny production. Generally, the three DE formulations tested were equally effective against S. onyzae adults. During the first 270 d of storage, the DE formulations were equally effective on both grains tested, but from 315 d of storage and on, S. oryzae mortality was higher on barley than on wheat. At this interval, progeny production was gradually increased, especially on grains treated with the lowest DE dose rate. However, even this rate caused a satisfactory level of mortality (> 90% after 14 d of exposure) during the first 270 d of storage.
评估了三种硅藻土（DE）制剂Insecto、PyriSec和SilicoSec对大麦和小麦上米象（Sitophilus oryzae (L.)）的杀虫和残留效果。为此，将4千克批次的大麦和小麦用上述DE制剂以三种剂量率（0.75、1和1.5克/千克谷物）进行处理，并在26摄氏度下储存。这些批次的样品在储存当天以及每隔45天采集一次，直至完成450天的储存期。通过将米象成虫暴露于这些样品，在26摄氏度和57%相对湿度下进行生物测定。在这些生物测定中，通过记录处理后的谷物上暴露24小时、48小时、7天和14天后的成虫死亡率来评估DE的效果。在14天计数后，将所有成虫移除，样品在相同条件下再放置45天，以评估处理后的谷物中产生后代的能力。暴露14天后的成虫死亡率随时间呈指数下降。在储存的前270天内，死亡率>90%，每个样品的后代产生量<1只成虫，而在270天后成虫死亡率逐渐下降，后代产生量随之增加。一般来说，所测试的三种DE制剂对米象成虫的效果相同。在储存的前270天内，DE制剂对两种测试谷物的效果相同，但从储存315天及以后，大麦上的米象死亡率高于小麦。在此期间，后代产生量逐渐增加，尤其是在用最低DE剂量率处理的谷物上。然而，即使是这个剂量率在储存的前270天内也导致了令人满意的死亡率水平（暴露14天后>90%）。
