Lin-Yan Zhao

The migratory locust, Locusta migratoria migratorioides (Fairmaire et L.J. Reiche) (Insecta: Orthoptera) (syn. L. m. manilensis), exhibits polarization-sensitive (polarotactic) aggregation behavior that can be exploited for behavioral control. This study elucidates the effects of circumferential vector combination patterns generated by linearly polarized and polarization-detection violet (520 nm) + orange (610 nm) lighting systems on locust aggregation. Using standard, linearly polarized, and polarization-detection lighting devices, we quantified phototactic and polarotactic aggregation responses under controlled breeding-shed conditions to assess sensitivity differences. The results indicate that polarization characteristics are the primary determinants of differential sensitivity between polarotactic and phototactic aggregation, mediated by circumferential vector combination patterns. Light exposure duration significantly influenced aggregation responses; at 9.0 h, the polarization-detection device VI elicited the strongest polarotactic aggregation response, whereas device I induced the strongest phototactic aggregation response. Furthermore, the circumferential vector patterns produced by linearly polarized device III and polarization-detection device VI were most effective in inducing polarotaxis. These findings demonstrate that locust visual sensitivity is regulated by heterogeneous polarization properties of light and modulated by exposure duration. Leveraging the dependence of polarotactic sensitivity on specific vector combination patterns, particularly the optimal performance of device VI and the suboptimal effect of device III, at 9.0 h strategic deployment of such lighting systems can disrupt celestial polarization-based navigation. This provides a practical basis for locust behavioral control and contributes behavioral evidence on polarization-guided aggregation in locusts.

Locusta migratoria manilensis exhibits polarization-sensitive (polarotactic) aggregation be havior that can be exploited for behavioral control. This study elucidates the effects of cir-cumferential vector combination patterns generated by linearly polarized and polariza-tion-detection violet+orange lighting systems on locust aggregation. Using standard, line-arly polarized, and polarization-detection lighting devices, we quantified phototactic and polarotactic aggregation responses under controlled breeding-shed conditions to assess sensitivity differences. The results indicate that polarization characteristics are the prima-ry determinants of differential sensitivity between polarotactic and phototactic aggrega-tion, mediated by circumferential vector combination patterns. Light exposure duration significantly influenced aggregation responses; at 9.0 h, the polarization-detection device VI elicited the strongest polarotactic aggregation, whereas device I induced the highest phototactic response. Furthermore, the circumferential vector patterns produced by linear-ly polarized device III and polarization-detection device VI were most effective in inducing polarotaxis. These findings demonstrate that locust visual sensitivity is regulated by het-erogeneous polarization properties of light and modulated by exposure duration. Lever-aging the dependence of polarotactic sensitivity on specific vector combination patterns, particularly the optimal performance of device VI and the secondary effect of device III, at 9.0 h strategic deployment of such lighting systems can disrupt celestial polariza-tion-based navigation. This provides a practical basis for locust behavioral control and advances the mechanistic understanding of polarization vision in locusts.

The rapid evolution of metabolic resistance to chemical insecticides and the adaptation to plant allelochemicals in insect pests have become major challenges in global pest management. While the overexpression of cytochrome P450 monooxygenases (P450s) is a well-recognized classic detoxification mechanism, the upstream epigenetic and post-transcriptional regulatory networks governing this process have only recently been elucidated. In this narrative review, the latest research progress on microRNAs (miRNAs) as crucial “fine-tuners” in insect detoxification networks is systematically summarized. The classic regulatory model is highlighted: the induced or constitutive downregulation of specific miRNAs relieves the translational repression of their target P450 genes, thereby contributing to metabolic resistance to major insecticide classes, including neonicotinoids, diamides, and pro-insecticides. Furthermore, the evolutionary recruitment mechanisms of conserved miRNAs in host plant adaptation are explored, and how endocrine signals, such as juvenile hormone (JH) and 20-hydroxyecdysone (20E), synergistically regulate the miRNA–P450 axis is analyzed. The “sponge effect”, wherein highly expressed P450 mRNAs act as competitive endogenous RNAs (ceRNAs) to sequester miRNAs, and the consequent physiological trade-offs (fitness costs) resulting from the prioritization of metabolic resources toward the detoxification system are comprehensively discussed. Finally, the current core methodologies for miRNA functional validation are critically evaluated, and the application potential and ecological safety prerequisites of miRNA-based nanobiopesticides for targeted and sustainable pest management are discussed. By integrating mechanistic insights with translational perspectives, this review highlights miRNA–P450 regulatory networks as key determinants of insecticide resistance evolution and as promising targets for developing more precise, environmentally compatible pest-management strategies.

Locusta migratoria manilensis causes frequent locust outbreaks in China. This study addresses technical barriers to developing monitoring and control methods based on optical traps. We examined the synergistic effects of spectral light and linear polarized light, and their relationship to visual aggregation under partially polarized illumination. Results showed that the coupling of unpolarized and polarized components within partially polarized light determines the effectiveness of polarized spectral vector illumination on locust aggregation sensitivity. Spectral characteristics modulate polarization-dependent visual sensitivity and affect synergy between spectral and polarized light. The induction of aggregation depended on both the spectral properties of partially polarized light and the illumination parameters. Among the tested conditions, unpolarized violet light combined with linearly polarized orange light at a 270° vector angle produced the strongest time-dependent effect, followed by unpolarized orange light combined with linearly polarized violet light at 0°. The combined stimulation of spectral and polarized-light-triggered aggregation through polarization-enhanced polarotaxis and spectrum-driven phototaxis. This behavior appears to result from nonlinear regulation between unpolarized and polarized components, which increases directional sensitivity for orientation. These findings show that partially polarized light can effectively trap locusts, promote aggregation, and interfere with navigation, providing a basis for improved optical control strategies.