Investigation of locust polartactic aggregation sensitivity to linearly polarized spectrum vector light in breeding sheds

This paper aimed to verify the validity of the polartactic effect induced in locusts by linearly polarized light, determine locust polartactic sensitivity characteristics, and develop a locust polarization induction light source by using manufactured violet, orange, and linearly polarized light sources. The phototactic and polartactic aggregation sensitivity of East Asian migratory locust populations raised in sheds was also investigated. The objective was to analyze the difference between locust phototactic and polartactic aggregation sensitivity and between locust polartactic aggregation response features and to discuss the polarization function mechanism and the influencing factors of the locust polartactic aggregation response. The results showed that the long- and short-spectrum properties of the violet and orange spectra affected the difference between locust phototactic and polartactic aggregation sensitivity. However, no matter what kind of spectrum was used, the polartactic aggregation effect induced in locusts by linearly polarized 0°, 90°, 180°, and 270° vector light was superior to the phototactic aggregation effect, and linearly polarized spectrum attributes did not affect the photo-induced effects caused by the sequential sensitivity vector (270°, 180°, 0°, 90°), whereas the regulation enhancement effect of light time on the sensitivity difference was related to spectral attributes. As light time was advanced to 5:30, locust polartactic aggregation sensitivity became the strongest. Spectral attributes, light time, temperature, and humidity factors in locust habitat did not change the vector sensitivity mode of locust polartactic aggregation and the vector periodic tuning response characteristics with cosine features. However, spectral attributes affected locust polartactic aggregation sensitivity, and the sensitivity to violet spectrum was superior to orange spectrum at a given light time, whereas the enhancement effect of orange spectrum with advancing light time was stronger than that of violet spectrum. The findings provide theoretical support for characterizing the specific sensitivity essence of locust phototactic and polartactic vision and determining the locust polarized spectrum induction mechanism.