Li Yanyu, Agarwal Manjree, Cao Yang, Ren Yonglin
School of Veterinary and Life Sciences, Murdoch University, Perth, Australia.
Stored Grain Research Laboratory, Academy of State Administration of Grain, Beijing, China.
Pest Manag Sci. 2020 Jan;76(1):314-323. doi: 10.1002/ps.5517. Epub 2019 Aug 5.
Synthetic amorphous silica (SAS) is safe for human consumption. SAS damages insect cuticles. Qualitative measurement of cuticle properties of insects affected by SAS is essential to understand the mode of action and develop new pesticides. A hyperspectral reflectance imaging approach was used to directly indicate the impact of SAS on the insect cuticle.
There were significant differences in the LT values of hydrophobic and hydrophilic SAS against Tribolium castaneum and Sitophilus oryzae (P < 0.01). T. castaneum was more susceptible to hydrophobic SAS while no difference was found for S. oryzae exposed to both SAS types. In a hyperspectral study, the ventral reflectance of control groups was higher than that of SAS-treated groups in both visible and short-wave near-infrared wavelength ranges. The SAS-treated groups showed much higher dorsal reflectance. The differences in absorption characteristics of cuticular fat and protein may contribute to the varied performance. The effects of both SASs on insect cuticles was significant, as the 100% recognition rate of the back propagation neural network models suggested. Consistent with the assumption that the efficacy was different between the two SAS types, the lowest rates of the model for two treatment groups were 62.2 and 73.3% in the target and output class.
The efficacy varied considerably between the two insect species and the two SASs. Hyperspectral image analyzing coupled with back propagation artificial neural network accurately recorded how SAS impacts the insect cuticle via the effective wavelengths. These findings showed that SAS is a promising candidate for new pesticide products. © 2019 Society of Chemical Industry.
合成无定形二氧化硅（SAS）对人类食用是安全的。SAS会损害昆虫的表皮。定性测量受SAS影响的昆虫表皮特性对于理解其作用模式和开发新型杀虫剂至关重要。采用高光谱反射成像方法直接表明SAS对昆虫表皮的影响。
疏水性和亲水性SAS对赤拟谷盗和米象的LT值存在显著差异（P < 0.01）。赤拟谷盗对疏水性SAS更敏感，而暴露于两种类型SAS的米象未发现差异。在高光谱研究中，对照组在可见光和短波近红外波长范围内的腹侧反射率高于SAS处理组。SAS处理组的背侧反射率要高得多。表皮脂肪和蛋白质吸收特性的差异可能导致了不同的表现。正如反向传播神经网络模型100%的识别率所表明的，两种SAS对昆虫表皮的影响都是显著的。与两种SAS类型功效不同的假设一致，两个处理组模型在目标和输出类别的最低识别率分别为62.2%和73.3%。
两种昆虫物种和两种SAS之间的功效差异很大。高光谱图像分析与反向传播人工神经网络相结合，通过有效波长准确记录了SAS对昆虫表皮的影响。这些发现表明，SAS是新型农药产品的一个有前景的候选者。© 2019化学工业协会。
